Examples about Opengl

Examples Opengl

aaindex.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** aaindex.c* This program draws shows how to draw anti-aliased lines in color

  * index mode. It draws two diagonal lines to form an X; when ‘r’

  * is typed in the window, the lines are rotated in opposite

  * directions.

  */

  #include <GL/glut.h>

  #include “stdlib.h”

• #define RAMPSIZE 16#define RAMP1START 32#define RAMP2START 48
• static float rotAngle = 0.;
• /* Initialize antialiasing for color index mode,* including loading a green color ramp starting* at RAMP1START, and a blue color ramp starting

  * at RAMP2START. The ramps must be a multiple of 16.

  */

  void init(void)

  {

  int i;

• for (i = 0; i < RAMPSIZE; i++) {GLfloat shade;shade = (GLfloat) i/(GLfloat) RAMPSIZE;

  glutSetColor(RAMP1START+(GLint)i, 0., shade, 0.);

  glutSetColor(RAMP2START+(GLint)i, 0., 0., shade);

  }

• glEnable (GL_LINE_SMOOTH);glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE);glLineWidth (1.5);
• glClearIndex ((GLfloat) RAMP1START);}
• /* Draw 2 diagonal lines to form an X*/void display(void)

  {

  glClear(GL_COLOR_BUFFER_BIT);

• glIndexi(RAMP1START);glPushMatrix();glRotatef(-rotAngle, 0.0, 0.0, 0.1);glBegin (GL_LINES);

  glVertex2f (-0.5, 0.5);

  glVertex2f (0.5, -0.5);

  glEnd ();

  glPopMatrix();

• glIndexi(RAMP2START);glPushMatrix();glRotatef(rotAngle, 0.0, 0.0, 0.1);

  glBegin (GL_LINES);

  glVertex2f (0.5, 0.5);

  glVertex2f (-0.5, -0.5);

  glEnd ();

  glPopMatrix();

• glFlush();}
• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  gluOrtho2D (-1.0, 1.0,

  -1.0*(GLfloat)h/(GLfloat)w, 1.0*(GLfloat)h/(GLfloat)w);

  else

  gluOrtho2D (-1.0*(GLfloat)w/(GLfloat)h,

  1.0*(GLfloat)w/(GLfloat)h, -1.0, 1.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘r’:

  case ‘R’:

  rotAngle += 20.;

  if (rotAngle >= 360.) rotAngle = 0.;

  glutPostRedisplay();

  break;

  case 27: /* Escape Key */

  exit(0);

  break;

  default:

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* color index display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_INDEX);

  glutInitWindowSize (200, 200);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc (reshape);

  glutKeyboardFunc (keyboard);

  glutDisplayFunc (display);

  glutMainLoop();

  return 0;

  }

aargb.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** aargb.c* This program draws shows how to draw anti-aliased lines. It draws

  * two diagonal lines to form an X; when ‘r’ is typed in the window,

  * the lines are rotated in opposite directions.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• static float rotAngle = 0.;
• /* Initialize antialiasing for RGBA mode, including alpha* blending, hint, and line width. Print out implementation* specific info on line width granularity and width.

  */

  void init(void)

  {

  GLfloat values[2];

  glGetFloatv (GL_LINE_WIDTH_GRANULARITY, values);

  printf (“GL_LINE_WIDTH_GRANULARITY value is %3.1f\n”, values[0]);

• glGetFloatv (GL_LINE_WIDTH_RANGE, values);printf (“GL_LINE_WIDTH_RANGE values are %3.1f %3.1f\n”,values[0], values[1]);
• glEnable (GL_LINE_SMOOTH);glEnable (GL_BLEND);glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE);

  glLineWidth (1.5);

• glClearColor(0.0, 0.0, 0.0, 0.0);}
• /* Draw 2 diagonal lines to form an X*/void display(void)

  {

  glClear(GL_COLOR_BUFFER_BIT);

• glColor3f (0.0, 1.0, 0.0);glPushMatrix();glRotatef(-rotAngle, 0.0, 0.0, 0.1);

  glBegin (GL_LINES);

  glVertex2f (-0.5, 0.5);

  glVertex2f (0.5, -0.5);

  glEnd ();

  glPopMatrix();

• glColor3f (0.0, 0.0, 1.0);glPushMatrix();glRotatef(rotAngle, 0.0, 0.0, 0.1);

  glBegin (GL_LINES);

  glVertex2f (0.5, 0.5);

  glVertex2f (-0.5, -0.5);

  glEnd ();

  glPopMatrix();

• glFlush();}
• void reshape(int w, int h){glViewport(0, 0, w, h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  gluOrtho2D (-1.0, 1.0,

  -1.0*(GLfloat)h/(GLfloat)w, 1.0*(GLfloat)h/(GLfloat)w);

  else

  gluOrtho2D (-1.0*(GLfloat)w/(GLfloat)h,

  1.0*(GLfloat)w/(GLfloat)h, -1.0, 1.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘r’:

  case ‘R’:

  rotAngle += 20.;

  if (rotAngle >= 360.) rotAngle = 0.;

  glutPostRedisplay();

  break;

  case 27: /* Escape Key */

  exit(0);

  break;

  default:

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (200, 200);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc (reshape);

  glutKeyboardFunc (keyboard);

  glutDisplayFunc (display);

  glutMainLoop();

  return 0;

  }

accanti.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* accanti.c* Use the accumulation buffer to do full-scene antialiasing* on a scene with orthographic parallel projection.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include “jitter.h”

• /* Initialize lighting and other values.*/void init(void)

  {

  GLfloat mat_ambient[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat light_position[] = { 0.0, 0.0, 10.0, 1.0 };

  GLfloat lm_ambient[] = { 0.2, 0.2, 0.2, 1.0 };

• glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);glMaterialf(GL_FRONT, GL_SHININESS, 50.0);

  glLightfv(GL_LIGHT0, GL_POSITION, light_position);

  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lm_ambient);glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

  glEnable(GL_DEPTH_TEST);

  glShadeModel (GL_FLAT);

• glClearColor(0.0, 0.0, 0.0, 0.0);glClearAccum(0.0, 0.0, 0.0, 0.0);}
• void displayObjects(void){GLfloat torus_diffuse[] = { 0.7, 0.7, 0.0, 1.0 };

  GLfloat cube_diffuse[] = { 0.0, 0.7, 0.7, 1.0 };

  GLfloat sphere_diffuse[] = { 0.7, 0.0, 0.7, 1.0 };

  GLfloat octa_diffuse[] = { 0.7, 0.4, 0.4, 1.0 };glPushMatrix ();

  glRotatef (30.0, 1.0, 0.0, 0.0);

• glPushMatrix ();glTranslatef (-0.80, 0.35, 0.0);glRotatef (100.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, torus_diffuse);

  glutSolidTorus (0.275, 0.85, 16, 16);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (-0.75, -0.50, 0.0);glRotatef (45.0, 0.0, 0.0, 1.0);

  glRotatef (45.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, cube_diffuse);

  glutSolidCube (1.5);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (0.75, 0.60, 0.0);glRotatef (30.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, sphere_diffuse);

  glutSolidSphere (1.0, 16, 16);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (0.70, -0.90, 0.25);glMaterialfv(GL_FRONT, GL_DIFFUSE, octa_diffuse);

  glutSolidOctahedron ();

  glPopMatrix ();

• glPopMatrix ();}
• #define ACSIZE 8
• void display(void){GLint viewport[4];

  int jitter;

• glGetIntegerv (GL_VIEWPORT, viewport);
• glClear(GL_ACCUM_BUFFER_BIT);for (jitter = 0; jitter < ACSIZE; jitter++) {glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glPushMatrix ();

  /* Note that 4.5 is the distance in world space between

  * left and right and bottom and top.

  * This formula converts fractional pixel movement to

  * world coordinates.

  */

  glTranslatef (j8[jitter].x*4.5/viewport[2],

  j8[jitter].y*4.5/viewport[3], 0.0);

  displayObjects ();

  glPopMatrix ();

  glAccum(GL_ACCUM, 1.0/ACSIZE);

  }

  glAccum (GL_RETURN, 1.0);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-2.25, 2.25, -2.25*h/w, 2.25*h/w, -10.0, 10.0);

  else

  glOrtho (-2.25*w/h, 2.25*w/h, -2.25, 2.25, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop* Be certain to request an accumulation buffer.*/

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB

  | GLUT_ACCUM | GLUT_DEPTH);

  glutInitWindowSize (250, 250);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

accpersp.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* accpersp.c* Use the accumulation buffer to do full-scene antialiasing* on a scene with perspective projection, using the special

  * routines accFrustum() and accPerspective().

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <math.h>

  #include “jitter.h”

• #ifdef WIN32#define near zNear#define far zFar

  #endif

• #define PI_ 3.14159265358979323846
• /* accFrustum()* The first 6 arguments are identical to the glFrustum() call.*

  * pixdx and pixdy are anti-alias jitter in pixels.

  * Set both equal to 0.0 for no anti-alias jitter.

  * eyedx and eyedy are depth-of field jitter in pixels.

  * Set both equal to 0.0 for no depth of field effects.

  *

  * focus is distance from eye to plane in focus.

  * focus must be greater than, but not equal to 0.0.

  *

  * Note that accFrustum() calls glTranslatef(). You will

  * probably want to insure that your ModelView matrix has been

  * initialized to identity before calling accFrustum().

  */

  void accFrustum(GLdouble left, GLdouble right, GLdouble bottom,

  GLdouble top, GLdouble near, GLdouble far, GLdouble pixdx,

  GLdouble pixdy, GLdouble eyedx, GLdouble eyedy, GLdouble focus)

  {

  GLdouble xwsize, ywsize;

  GLdouble dx, dy;

  GLint viewport[4];

• glGetIntegerv (GL_VIEWPORT, viewport);xwsize = right – left;ywsize = top – bottom;dx = -(pixdx*xwsize/(GLdouble) viewport[2] + eyedx*near/focus);

  dy = -(pixdy*ywsize/(GLdouble) viewport[3] + eyedy*near/focus);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  glFrustum (left + dx, right + dx, bottom + dy, top + dy, near, far);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  glTranslatef (-eyedx, -eyedy, 0.0);

  }

• /* accPerspective()** The first 4 arguments are identical to the gluPerspective() call.

  * pixdx and pixdy are anti-alias jitter in pixels.

  * Set both equal to 0.0 for no anti-alias jitter.

  * eyedx and eyedy are depth-of field jitter in pixels.

  * Set both equal to 0.0 for no depth of field effects.

  *

  * focus is distance from eye to plane in focus.

  * focus must be greater than, but not equal to 0.0.

  *

  * Note that accPerspective() calls accFrustum().

  */

  void accPerspective(GLdouble fovy, GLdouble aspect,

  GLdouble near, GLdouble far, GLdouble pixdx, GLdouble pixdy,

  GLdouble eyedx, GLdouble eyedy, GLdouble focus)

  {

  GLdouble fov2,left,right,bottom,top;

• fov2 = ((fovy*PI_) / 180.0) / 2.0;
• top = near / (cos(fov2) / sin(fov2));bottom = -top;
• right = top * aspect;left = -right;
• accFrustum (left, right, bottom, top, near, far,pixdx, pixdy, eyedx, eyedy, focus);}
• /* Initialize lighting and other values.*/void init(void)

  {

  GLfloat mat_ambient[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat light_position[] = { 0.0, 0.0, 10.0, 1.0 };

  GLfloat lm_ambient[] = { 0.2, 0.2, 0.2, 1.0 };

• glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);glMaterialf(GL_FRONT, GL_SHININESS, 50.0);

  glLightfv(GL_LIGHT0, GL_POSITION, light_position);

  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lm_ambient);glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

  glEnable(GL_DEPTH_TEST);

  glShadeModel (GL_FLAT);

• glClearColor(0.0, 0.0, 0.0, 0.0);glClearAccum(0.0, 0.0, 0.0, 0.0);}
• void displayObjects(void){GLfloat torus_diffuse[] = { 0.7, 0.7, 0.0, 1.0 };

  GLfloat cube_diffuse[] = { 0.0, 0.7, 0.7, 1.0 };

  GLfloat sphere_diffuse[] = { 0.7, 0.0, 0.7, 1.0 };

  GLfloat octa_diffuse[] = { 0.7, 0.4, 0.4, 1.0 };glPushMatrix ();

  glTranslatef (0.0, 0.0, -5.0);

  glRotatef (30.0, 1.0, 0.0, 0.0);

• glPushMatrix ();glTranslatef (-0.80, 0.35, 0.0);glRotatef (100.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, torus_diffuse);

  glutSolidTorus (0.275, 0.85, 16, 16);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (-0.75, -0.50, 0.0);glRotatef (45.0, 0.0, 0.0, 1.0);

  glRotatef (45.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, cube_diffuse);

  glutSolidCube (1.5);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (0.75, 0.60, 0.0);glRotatef (30.0, 1.0, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, sphere_diffuse);

  glutSolidSphere (1.0, 16, 16);

  glPopMatrix ();

• glPushMatrix ();glTranslatef (0.70, -0.90, 0.25);glMaterialfv(GL_FRONT, GL_DIFFUSE, octa_diffuse);

  glutSolidOctahedron ();

  glPopMatrix ();

• glPopMatrix ();}
• #define ACSIZE 8
• void display(void){GLint viewport[4];

  int jitter;

• glGetIntegerv (GL_VIEWPORT, viewport);
• glClear(GL_ACCUM_BUFFER_BIT);for (jitter = 0; jitter < ACSIZE; jitter++) {glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  accPerspective (50.0,

  (GLdouble) viewport[2]/(GLdouble) viewport[3],

  1.0, 15.0, j8[jitter].x, j8[jitter].y, 0.0, 0.0, 1.0);

  displayObjects ();

  glAccum(GL_ACCUM, 1.0/ACSIZE);

  }

  glAccum (GL_RETURN, 1.0);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop* Be certain you request an accumulation buffer.*/

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB

  | GLUT_ACCUM | GLUT_DEPTH);

  glutInitWindowSize (250, 250);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

alpha.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** alpha.c* This program draws several overlapping filled polygons

  * to demonstrate the effect order has on alpha blending results.

  * Use the ‘t’ key to toggle the order of drawing polygons.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• static int leftFirst = GL_TRUE;
• /* Initialize alpha blending function.*/static void init(void)

  {

  glEnable (GL_BLEND);

  glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  glShadeModel (GL_FLAT);

  glClearColor (0.0, 0.0, 0.0, 0.0);

  }

• static void drawLeftTriangle(void){/* draw yellow triangle on LHS of screen */
• glBegin (GL_TRIANGLES);glColor4f(1.0, 1.0, 0.0, 0.75);glVertex3f(0.1, 0.9, 0.0);

  glVertex3f(0.1, 0.1, 0.0);

  glVertex3f(0.7, 0.5, 0.0);

  glEnd();

  }

• static void drawRightTriangle(void){/* draw cyan triangle on RHS of screen */
• glBegin (GL_TRIANGLES);glColor4f(0.0, 1.0, 1.0, 0.75);glVertex3f(0.9, 0.9, 0.0);

  glVertex3f(0.3, 0.5, 0.0);

  glVertex3f(0.9, 0.1, 0.0);

  glEnd();

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT);
• if (leftFirst) {drawLeftTriangle();drawRightTriangle();

  }

  else {

  drawRightTriangle();

  drawLeftTriangle();

  }

• glFlush();}
• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  gluOrtho2D (0.0, 1.0, 0.0, 1.0*(GLfloat)h/(GLfloat)w);

  else

  gluOrtho2D (0.0, 1.0*(GLfloat)w/(GLfloat)h, 0.0, 1.0);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘t’:

  case ‘T’:

  leftFirst = !leftFirst;

  glutPostRedisplay();

  break;

  case 27: /* Escape key */

  exit(0);

  break;

  default:

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (200, 200);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc (reshape);

  glutKeyboardFunc (keyboard);

  glutDisplayFunc (display);

  glutMainLoop();

  return 0;

  }

bezcurve.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* bezcurve.c* This program uses evaluators to draw a Bezier curve.*/

  #include <GL/glut.h>

  #include <stdlib.h>

• GLfloat ctrlpoints[4][3] = {{ -4.0, -4.0, 0.0}, { -2.0, 4.0, 0.0},{2.0, -4.0, 0.0}, {4.0, 4.0, 0.0}};
• void init(void){glClearColor(0.0, 0.0, 0.0, 0.0);

  glShadeModel(GL_FLAT);

  glMap1f(GL_MAP1_VERTEX_3, 0.0, 1.0, 3, 4, &ctrlpoints[0][0]);

  glEnable(GL_MAP1_VERTEX_3);

  }

• void display(void){int i;
• glClear(GL_COLOR_BUFFER_BIT);glColor3f(1.0, 1.0, 1.0);glBegin(GL_LINE_STRIP);

  for (i = 0; i <= 30; i++)

  glEvalCoord1f((GLfloat) i/30.0);

  glEnd();

  /* The following code displays the control points as dots. */

  glPointSize(5.0);

  glColor3f(1.0, 1.0, 0.0);

  glBegin(GL_POINTS);

  for (i = 0; i < 4; i++)

  glVertex3fv(&ctrlpoints[i][0]);

  glEnd();

  glFlush();

• }
• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho(-5.0, 5.0, -5.0*(GLfloat)h/(GLfloat)w,

  5.0*(GLfloat)h/(GLfloat)w, -5.0, 5.0);

  else

  glOrtho(-5.0*(GLfloat)w/(GLfloat)h,

  5.0*(GLfloat)w/(GLfloat)h, -5.0, 5.0, -5.0, 5.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

bezmesh.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* bezmesh.c* This program renders a lighted, filled Bezier surface,* using two-dimensional evaluators.

  */

  #include <stdlib.h>

  #include <GL/glut.h>

• GLfloat ctrlpoints[4][4][3] = {{ {-1.5, -1.5, 4.0},{-0.5, -1.5, 2.0},

  {0.5, -1.5, -1.0},

  {1.5, -1.5, 2.0}},

  { {-1.5, -0.5, 1.0},

  {-0.5, -0.5, 3.0},

  {0.5, -0.5, 0.0},

  {1.5, -0.5, -1.0}},

  { {-1.5, 0.5, 4.0},

  {-0.5, 0.5, 0.0},

  {0.5, 0.5, 3.0},

  {1.5, 0.5, 4.0}},

  { {-1.5, 1.5, -2.0},

  {-0.5, 1.5, -2.0},

  {0.5, 1.5, 0.0},

  {1.5, 1.5, -1.0}}

  };

• void initlights(void){GLfloat ambient[] = {0.2, 0.2, 0.2, 1.0};

  GLfloat position[] = {0.0, 0.0, 2.0, 1.0};

  GLfloat mat_diffuse[] = {0.6, 0.6, 0.6, 1.0};

  GLfloat mat_specular[] = {1.0, 1.0, 1.0, 1.0};

  GLfloat mat_shininess[] = {50.0};

• glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);
• glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);glLightfv(GL_LIGHT0, GL_POSITION, position);
• glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glPushMatrix();

  glRotatef(85.0, 1.0, 1.0, 1.0);

  glEvalMesh2(GL_FILL, 0, 20, 0, 20);

  glPopMatrix();

  glFlush();

  }

• void init(void){glClearColor(0.0, 0.0, 0.0, 0.0);

  glEnable(GL_DEPTH_TEST);

  glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,

  0, 1, 12, 4, &ctrlpoints[0][0][0]);

  glEnable(GL_MAP2_VERTEX_3);

  glEnable(GL_AUTO_NORMAL);

  glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);

  initlights(); /* for lighted version only */

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho(-4.0, 4.0, -4.0*(GLfloat)h/(GLfloat)w,

  4.0*(GLfloat)h/(GLfloat)w, -4.0, 4.0);

  else

  glOrtho(-4.0*(GLfloat)w/(GLfloat)h,

  4.0*(GLfloat)w/(GLfloat)h, -4.0, 4.0, -4.0, 4.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char **argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

bezsurf.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* bezsurf.c* This program renders a wireframe Bezier surface,* using two-dimensional evaluators.

  */

  #include <stdlib.h>

  #include <GL/glut.h>

• GLfloat ctrlpoints[4][4][3] = {{{-1.5, -1.5, 4.0}, {-0.5, -1.5, 2.0},{0.5, -1.5, -1.0}, {1.5, -1.5, 2.0}},

  {{-1.5, -0.5, 1.0}, {-0.5, -0.5, 3.0},

  {0.5, -0.5, 0.0}, {1.5, -0.5, -1.0}},

  {{-1.5, 0.5, 4.0}, {-0.5, 0.5, 0.0},

  {0.5, 0.5, 3.0}, {1.5, 0.5, 4.0}},

  {{-1.5, 1.5, -2.0}, {-0.5, 1.5, -2.0},

  {0.5, 1.5, 0.0}, {1.5, 1.5, -1.0}}

  };

• void display(void){int i, j;
• glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);glColor3f(1.0, 1.0, 1.0);glPushMatrix ();

  glRotatef(85.0, 1.0, 1.0, 1.0);

  for (j = 0; j <= 8; j++) {

  glBegin(GL_LINE_STRIP);

  for (i = 0; i <= 30; i++)

  glEvalCoord2f((GLfloat)i/30.0, (GLfloat)j/8.0);

  glEnd();

  glBegin(GL_LINE_STRIP);

  for (i = 0; i <= 30; i++)

  glEvalCoord2f((GLfloat)j/8.0, (GLfloat)i/30.0);

  glEnd();

  }

  glPopMatrix ();

  glFlush();

  }

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,

  0, 1, 12, 4, &ctrlpoints[0][0][0]);

  glEnable(GL_MAP2_VERTEX_3);

  glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);

  glEnable(GL_DEPTH_TEST);

  glShadeModel(GL_FLAT);

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho(-4.0, 4.0, -4.0*(GLfloat)h/(GLfloat)w,

  4.0*(GLfloat)h/(GLfloat)w, -4.0, 4.0);

  else

  glOrtho(-4.0*(GLfloat)w/(GLfloat)h,

  4.0*(GLfloat)w/(GLfloat)h, -4.0, 4.0, -4.0, 4.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

colormat.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** colormat.c* After initialization, the program will be in

  * ColorMaterial mode. Interaction: pressing the

  * mouse buttons will change the diffuse reflection values.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• GLfloat diffuseMaterial[4] = { 0.5, 0.5, 0.5, 1.0 };
• /* Initialize material property, light source, lighting model,* and depth buffer.*/

  void init(void)

  {

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };

• glClearColor (0.0, 0.0, 0.0, 0.0);glShadeModel (GL_SMOOTH);glEnable(GL_DEPTH_TEST);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, diffuseMaterial);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialf(GL_FRONT, GL_SHININESS, 25.0);

  glLightfv(GL_LIGHT0, GL_POSITION, light_position);

  glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

• glColorMaterial(GL_FRONT, GL_DIFFUSE);glEnable(GL_COLOR_MATERIAL);}
• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glutSolidSphere(1.0, 20, 16);

  glFlush ();

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-1.5, 1.5, -1.5*(GLfloat)h/(GLfloat)w,

  1.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho (-1.5*(GLfloat)w/(GLfloat)h,

  1.5*(GLfloat)w/(GLfloat)h, -1.5, 1.5, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void mouse(int button, int state, int x, int y){switch (button) {

  case GLUT_LEFT_BUTTON:

  if (state == GLUT_DOWN) {

  diffuseMaterial[0] += 0.1;

  if (diffuseMaterial[0] > 1.0)

  diffuseMaterial[0] = 0.0;

  glColor4fv(diffuseMaterial);

  glutPostRedisplay();

  }

  break;

  case GLUT_MIDDLE_BUTTON:

  if (state == GLUT_DOWN) {

  diffuseMaterial[1] += 0.1;

  if (diffuseMaterial[1] > 1.0)

  diffuseMaterial[1] = 0.0;

  glColor4fv(diffuseMaterial);

  glutPostRedisplay();

  }

  break;

  case GLUT_RIGHT_BUTTON:

  if (state == GLUT_DOWN) {

  diffuseMaterial[2] += 0.1;

  if (diffuseMaterial[2] > 1.0)

  diffuseMaterial[2] = 0.0;

  glColor4fv(diffuseMaterial);

  glutPostRedisplay();

  }

  break;

  default:

  break;

  }

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutMouseFunc(mouse);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

cube.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** cube.c* This program demonstrates a single modeling transformation,

  * glScalef() and a single viewing transformation, gluLookAt().

  * A wireframe cube is rendered.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_FLAT);

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT);

  glColor3f (1.0, 1.0, 1.0);

  glLoadIdentity (); /* clear the matrix */

  /* viewing transformation */

  gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

  glScalef (1.0, 2.0, 1.0); /* modeling transformation */

  glutWireCube (1.0);

  glFlush ();

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  glFrustum (-1.0, 1.0, -1.0, 1.0, 1.5, 20.0);

  glMatrixMode (GL_MODELVIEW);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

dof.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** dof.c* This program demonstrates use of the accumulation buffer to

  * create an out-of-focus depth-of-field effect. The teapots

  * are drawn several times into the accumulation buffer. The

  * viewing volume is jittered, except at the focal point, where

  * the viewing volume is at the same position, each time. In

  * this case, the gold teapot remains in focus.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <math.h>

  #include “jitter.h”

• #ifdef WIN32#define near zNear#define far zFar

  #endif

• #define PI_ 3.14159265358979323846
• GLuint teapotList;
• /* accFrustum()* The first 6 arguments are identical to the glFrustum() call.*

  * pixdx and pixdy are anti-alias jitter in pixels.

  * Set both equal to 0.0 for no anti-alias jitter.

  * eyedx and eyedy are depth-of field jitter in pixels.

  * Set both equal to 0.0 for no depth of field effects.

  *

  * focus is distance from eye to plane in focus.

  * focus must be greater than, but not equal to 0.0.

  *

  * Note that accFrustum() calls glTranslatef(). You will

  * probably want to insure that your ModelView matrix has been

  * initialized to identity before calling accFrustum().

  */

  void accFrustum(GLdouble left, GLdouble right, GLdouble bottom,

  GLdouble top, GLdouble near, GLdouble far, GLdouble pixdx,

  GLdouble pixdy, GLdouble eyedx, GLdouble eyedy, GLdouble focus)

  {

  GLdouble xwsize, ywsize;

  GLdouble dx, dy;

  GLint viewport[4];

• glGetIntegerv (GL_VIEWPORT, viewport);xwsize = right – left;ywsize = top – bottom;dx = -(pixdx*xwsize/(GLdouble) viewport[2] + eyedx*near/focus);

  dy = -(pixdy*ywsize/(GLdouble) viewport[3] + eyedy*near/focus);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  glFrustum (left + dx, right + dx, bottom + dy, top + dy, near, far);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  glTranslatef (-eyedx, -eyedy, 0.0);

  }

• /* accPerspective()** The first 4 arguments are identical to the gluPerspective() call.

  * pixdx and pixdy are anti-alias jitter in pixels.

  * Set both equal to 0.0 for no anti-alias jitter.

  * eyedx and eyedy are depth-of field jitter in pixels.

  * Set both equal to 0.0 for no depth of field effects.

  *

  * focus is distance from eye to plane in focus.

  * focus must be greater than, but not equal to 0.0.

  *

  * Note that accPerspective() calls accFrustum().

  */

  void accPerspective(GLdouble fovy, GLdouble aspect,

  GLdouble near, GLdouble far, GLdouble pixdx, GLdouble pixdy,

  GLdouble eyedx, GLdouble eyedy, GLdouble focus)

  {

  GLdouble fov2,left,right,bottom,top;

• fov2 = ((fovy*PI_) / 180.0) / 2.0;
• top = near / (cos(fov2) / sin(fov2));bottom = -top;
• right = top * aspect;left = -right;
• accFrustum (left, right, bottom, top, near, far,pixdx, pixdy, eyedx, eyedy, focus);}
• void init(void){GLfloat ambient[] = { 0.0, 0.0, 0.0, 1.0 };

  GLfloat diffuse[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat position[] = { 0.0, 3.0, 3.0, 0.0 };GLfloat lmodel_ambient[] = { 0.2, 0.2, 0.2, 1.0 };

  GLfloat local_view[] = { 0.0 };

• glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);glLightfv(GL_LIGHT0, GL_POSITION, position);glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);

  glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, local_view);

• glFrontFace (GL_CW);glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);

  glEnable(GL_AUTO_NORMAL);

  glEnable(GL_NORMALIZE);

  glEnable(GL_DEPTH_TEST);

• glClearColor(0.0, 0.0, 0.0, 0.0);glClearAccum(0.0, 0.0, 0.0, 0.0);/* make teapot display list */

  teapotList = glGenLists(1);

  glNewList (teapotList, GL_COMPILE);

  glutSolidTeapot (0.5);

  glEndList ();

  }

• void renderTeapot (GLfloat x, GLfloat y, GLfloat z,GLfloat ambr, GLfloat ambg, GLfloat ambb,GLfloat difr, GLfloat difg, GLfloat difb,

  GLfloat specr, GLfloat specg, GLfloat specb, GLfloat shine)

  {

  GLfloat mat[4];

• glPushMatrix();glTranslatef (x, y, z);mat[0] = ambr; mat[1] = ambg; mat[2] = ambb; mat[3] = 1.0;

  glMaterialfv (GL_FRONT, GL_AMBIENT, mat);

  mat[0] = difr; mat[1] = difg; mat[2] = difb;

  glMaterialfv (GL_FRONT, GL_DIFFUSE, mat);

  mat[0] = specr; mat[1] = specg; mat[2] = specb;

  glMaterialfv (GL_FRONT, GL_SPECULAR, mat);

  glMaterialf (GL_FRONT, GL_SHININESS, shine*128.0);

  glCallList(teapotList);

  glPopMatrix();

  }

• /* display() draws 5 teapots into the accumulation buffer* several times; each time with a jittered perspective.* The focal point is at z = 5.0, so the gold teapot will

  * stay in focus. The amount of jitter is adjusted by the

  * magnitude of the accPerspective() jitter; in this example, 0.33.

  * In this example, the teapots are drawn 8 times. See jitter.h

  */

  void display(void)

  {

  int jitter;

  GLint viewport[4];

• glGetIntegerv (GL_VIEWPORT, viewport);glClear(GL_ACCUM_BUFFER_BIT);
• for (jitter = 0; jitter < 8; jitter++) {glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);accPerspective (45.0,

  (GLdouble) viewport[2]/(GLdouble) viewport[3],

  1.0, 15.0, 0.0, 0.0,

  0.33*j8[jitter].x, 0.33*j8[jitter].y, 5.0);

• /* ruby, gold, silver, emerald, and cyan teapots */renderTeapot (-1.1, -0.5, -4.5, 0.1745, 0.01175,0.01175, 0.61424, 0.04136, 0.04136,

  0.727811, 0.626959, 0.626959, 0.6);

  renderTeapot (-0.5, -0.5, -5.0, 0.24725, 0.1995,

  0.0745, 0.75164, 0.60648, 0.22648,

  0.628281, 0.555802, 0.366065, 0.4);

  renderTeapot (0.2, -0.5, -5.5, 0.19225, 0.19225,

  0.19225, 0.50754, 0.50754, 0.50754,

  0.508273, 0.508273, 0.508273, 0.4);

  renderTeapot (1.0, -0.5, -6.0, 0.0215, 0.1745, 0.0215,

  0.07568, 0.61424, 0.07568, 0.633,

  0.727811, 0.633, 0.6);

  renderTeapot (1.8, -0.5, -6.5, 0.0, 0.1, 0.06, 0.0,

  0.50980392, 0.50980392, 0.50196078,

  0.50196078, 0.50196078, .25);

  glAccum (GL_ACCUM, 0.125);

  }

  glAccum (GL_RETURN, 1.0);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop* Be certain you request an accumulation buffer.*/

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB

  | GLUT_ACCUM | GLUT_DEPTH);

  glutInitWindowSize (400, 400);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

feedback.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** feedback.c* This program demonstrates use of OpenGL feedback. First,

  * a lighting environment is set up and a few lines are drawn.

  * Then feedback mode is entered, and the same lines are

  * drawn. The results in the feedback buffer are printed.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• /* Initialize lighting.*/void init(void)

  {

  glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

  }

• /* Draw a few lines and two points, one of which will* be clipped. If in feedback mode, a passthrough token* is issued between the each primitive.

  */

  void drawGeometry (GLenum mode)

  {

  glBegin (GL_LINE_STRIP);

  glNormal3f (0.0, 0.0, 1.0);

  glVertex3f (30.0, 30.0, 0.0);

  glVertex3f (50.0, 60.0, 0.0);

  glVertex3f (70.0, 40.0, 0.0);

  glEnd ();

  if (mode == GL_FEEDBACK)

  glPassThrough (1.0);

  glBegin (GL_POINTS);

  glVertex3f (-100.0, -100.0, -100.0); /* will be clipped */

  glEnd ();

  if (mode == GL_FEEDBACK)

  glPassThrough (2.0);

  glBegin (GL_POINTS);

  glNormal3f (0.0, 0.0, 1.0);

  glVertex3f (50.0, 50.0, 0.0);

  glEnd ();

  }

• /* Write contents of one vertex to stdout. */void print3DcolorVertex (GLint size, GLint *count,GLfloat *buffer)

  {

  int i;

• printf (” “);for (i = 0; i < 7; i++) {printf (“%4.2f “, buffer[size-(*count)]);

  *count = *count – 1;

  }

  printf (“\n”);

  }

• /* Write contents of entire buffer. (Parse tokens!) */void printBuffer(GLint size, GLfloat *buffer){

  GLint count;

  GLfloat token;

• count = size;while (count) {token = buffer[size-count]; count–;

  if (token == GL_PASS_THROUGH_TOKEN) {

  printf (“GL_PASS_THROUGH_TOKEN\n”);

  printf (” %4.2f\n”, buffer[size-count]);

  count–;

  }

  else if (token == GL_POINT_TOKEN) {

  printf (“GL_POINT_TOKEN\n”);

  print3DcolorVertex (size, &count, buffer);

  }

  else if (token == GL_LINE_TOKEN) {

  printf (“GL_LINE_TOKEN\n”);

  print3DcolorVertex (size, &count, buffer);

  print3DcolorVertex (size, &count, buffer);

  }

  else if (token == GL_LINE_RESET_TOKEN) {

  printf (“GL_LINE_RESET_TOKEN\n”);

  print3DcolorVertex (size, &count, buffer);

  print3DcolorVertex (size, &count, buffer);

  }

  }

  }

• void display(void){GLfloat feedBuffer[1024];

  GLint size;

• glMatrixMode (GL_PROJECTION);glLoadIdentity ();glOrtho (0.0, 100.0, 0.0, 100.0, 0.0, 1.0);
• glClearColor (0.0, 0.0, 0.0, 0.0);glClear(GL_COLOR_BUFFER_BIT);drawGeometry (GL_RENDER);
• glFeedbackBuffer (1024, GL_3D_COLOR, feedBuffer);(void) glRenderMode (GL_FEEDBACK);drawGeometry (GL_FEEDBACK);
• size = glRenderMode (GL_RENDER);printBuffer (size, feedBuffer);}
• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop */int main(int argc, char** argv){

  glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (100, 100);

  glutInitWindowPosition (100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutDisplayFunc(display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

fog.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** fog.c* This program draws 5 red spheres, each at a different

  * z distance from the eye, in different types of fog.

  * Pressing the f key chooses between 3 types of

  * fog: exponential, exponential squared, and linear.

  * In this program, there is a fixed density value, as well

  * as fixed start and end values for the linear fog.

  */

  #include <GL/glut.h>

  #include <math.h>

  #include <stdlib.h>

  #include <stdio.h>

• static GLint fogMode;
• /* Initialize depth buffer, fog, light source,* material property, and lighting model.*/

  static void init(void)

  {

  GLfloat position[] = { 0.5, 0.5, 3.0, 0.0 };

• glEnable(GL_DEPTH_TEST);
• glLightfv(GL_LIGHT0, GL_POSITION, position);glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);

  {

  GLfloat mat[3] = {0.1745, 0.01175, 0.01175};

  glMaterialfv (GL_FRONT, GL_AMBIENT, mat);

  mat[0] = 0.61424; mat[1] = 0.04136; mat[2] = 0.04136;

  glMaterialfv (GL_FRONT, GL_DIFFUSE, mat);

  mat[0] = 0.727811; mat[1] = 0.626959; mat[2] = 0.626959;

  glMaterialfv (GL_FRONT, GL_SPECULAR, mat);

  glMaterialf (GL_FRONT, GL_SHININESS, 0.6*128.0);

  }

• glEnable(GL_FOG);{GLfloat fogColor[4] = {0.5, 0.5, 0.5, 1.0};
• fogMode = GL_EXP;glFogi (GL_FOG_MODE, fogMode);glFogfv (GL_FOG_COLOR, fogColor);

  glFogf (GL_FOG_DENSITY, 0.35);

  glHint (GL_FOG_HINT, GL_DONT_CARE);

  glFogf (GL_FOG_START, 1.0);

  glFogf (GL_FOG_END, 5.0);

  }

  glClearColor(0.5, 0.5, 0.5, 1.0); /* fog color */

  }

• static void renderSphere (GLfloat x, GLfloat y, GLfloat z){glPushMatrix();

  glTranslatef (x, y, z);

  glutSolidSphere(0.4, 16, 16);

  glPopMatrix();

  }

• /* display() draws 5 spheres at different z positions.*/void display(void)

  {

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  renderSphere (-2., -0.5, -1.0);

  renderSphere (-1., -0.5, -2.0);

  renderSphere (0., -0.5, -3.0);

  renderSphere (1., -0.5, -4.0);

  renderSphere (2., -0.5, -5.0);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-2.5, 2.5, -2.5*(GLfloat)h/(GLfloat)w,

  2.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho (-2.5*(GLfloat)w/(GLfloat)h,

  2.5*(GLfloat)w/(GLfloat)h, -2.5, 2.5, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity ();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘f’:

  case ‘F’:

  if (fogMode == GL_EXP) {

  fogMode = GL_EXP2;

  printf (“Fog mode is GL_EXP2\n”);

  }

  else if (fogMode == GL_EXP2) {

  fogMode = GL_LINEAR;

  printf (“Fog mode is GL_LINEAR\n”);

  }

  else if (fogMode == GL_LINEAR) {

  fogMode = GL_EXP;

  printf (“Fog mode is GL_EXP\n”);

  }

  glFogi (GL_FOG_MODE, fogMode);

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, depth buffer, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize(500, 500);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc (reshape);

  glutKeyboardFunc (keyboard);

  glutDisplayFunc (display);

  glutMainLoop();

  return 0;

  }

fogindex.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** fogindex.c* This program draws 5 wireframe spheres, each at

  * a different z distance from the eye, in linear fog.

  */

  #include <GL/glut.h>

  #include <math.h>

  #include <stdlib.h>

  #include <stdio.h>

• /* Initialize color map and fog. Set screen clear color* to end of color ramp.*/

  #define NUMCOLORS 32

  #define RAMPSTART 16

• static void init(void){int i;
• glEnable(GL_DEPTH_TEST);
• for (i = 0; i < NUMCOLORS; i++) {GLfloat shade;shade = (GLfloat) (NUMCOLORS-i)/(GLfloat) NUMCOLORS;

  glutSetColor (RAMPSTART + i, shade, shade, shade);

  }

  glEnable(GL_FOG);

• glFogi (GL_FOG_MODE, GL_LINEAR);glFogi (GL_FOG_INDEX, NUMCOLORS);glFogf (GL_FOG_START, 1.0);

  glFogf (GL_FOG_END, 6.0);

  glHint (GL_FOG_HINT, GL_NICEST);

  glClearIndex((GLfloat) (NUMCOLORS+RAMPSTART-1));

  }

• static void renderSphere (GLfloat x, GLfloat y, GLfloat z){glPushMatrix();

  glTranslatef (x, y, z);

  glutWireSphere(0.4, 16, 16);

  glPopMatrix();

  }

• /* display() draws 5 spheres at different z positions.*/void display(void)

  {

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glIndexi (RAMPSTART);

• renderSphere (-2., -0.5, -1.0);renderSphere (-1., -0.5, -2.0);renderSphere (0., -0.5, -3.0);

  renderSphere (1., -0.5, -4.0);

  renderSphere (2., -0.5, -5.0);

• glFlush();}
• void reshape(int w, int h){glViewport(0, 0, w, h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-2.5, 2.5, -2.5*(GLfloat)h/(GLfloat)w,

  2.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho (-2.5*(GLfloat)w/(GLfloat)h,

  2.5*(GLfloat)w/(GLfloat)h, -2.5, 2.5, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity ();

  }

• void keyboard(unsigned char key, int x, int y){
• switch (key) {case 27:exit(0);

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* color index mode, depth buffer, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_INDEX | GLUT_DEPTH);

  glutInitWindowSize(500, 500);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc (reshape);

  glutKeyboardFunc (keyboard);

  glutDisplayFunc (display);

  glutMainLoop();

  return 0;

  }

image.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* image.c* This program demonstrates drawing pixels and shows the effect* of glDrawPixels(), glCopyPixels(), and glPixelZoom().

  * Interaction: moving the mouse while pressing the mouse button

  * will copy the image in the lower-left corner of the window

  * to the mouse position, using the current pixel zoom factors.

  * There is no attempt to prevent you from drawing over the original

  * image. If you press the ‘r’ key, the original image and zoom

  * factors are reset. If you press the ‘z’ or ‘Z’ keys, you change

  * the zoom factors.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• /* Create checkerboard image */#define checkImageWidth 64#define checkImageHeight 64

  GLubyte checkImage[checkImageHeight][checkImageWidth][3];

• static GLdouble zoomFactor = 1.0;static GLint height;
• void makeCheckImage(void){int i, j, c;for (i = 0; i < checkImageHeight; i++) {

  for (j = 0; j < checkImageWidth; j++) {

  c = ((((i&0x8)==0)^((j&0x8))==0))*255;

  checkImage[i][j][0] = (GLubyte) c;

  checkImage[i][j][1] = (GLubyte) c;

  checkImage[i][j][2] = (GLubyte) c;

  }

  }

  }

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel(GL_FLAT);

  makeCheckImage();

  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT);

  glRasterPos2i(0, 0);

  glDrawPixels(checkImageWidth, checkImageHeight, GL_RGB,

  GL_UNSIGNED_BYTE, checkImage);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  height = (GLint) h;

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluOrtho2D(0.0, (GLdouble) w, 0.0, (GLdouble) h);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void motion(int x, int y){static GLint screeny;screeny = height – (GLint) y;

  glRasterPos2i (x, screeny);

  glPixelZoom (zoomFactor, zoomFactor);

  glCopyPixels (0, 0, checkImageWidth, checkImageHeight, GL_COLOR);

  glPixelZoom (1.0, 1.0);

  glFlush ();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘r’:

  case ‘R’:

  zoomFactor = 1.0;

  glutPostRedisplay();

  printf (“zoomFactor reset to 1.0\n”);

• break;case ‘z’:zoomFactor += 0.5;

  if (zoomFactor >= 3.0)

  zoomFactor = 3.0;

  printf (“zoomFactor is now %4.1f\n”, zoomFactor);

  break;

  case ‘Z’:

  zoomFactor -= 0.5;

  if (zoomFactor <= 0.5)

  zoomFactor = 0.5;

  printf (“zoomFactor is now %4.1f\n”, zoomFactor);

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize(250, 250);

  glutInitWindowPosition(100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMotionFunc(motion);

  glutMainLoop();

  return 0;

  }

light.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** light.c* This program demonstrates the use of the OpenGL lighting

  * model. A sphere is drawn using a grey material characteristic.

  * A single light source illuminates the object.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• /* Initialize material property, light source, lighting model,* and depth buffer.*/

  void init(void)

  {

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat mat_shininess[] = { 50.0 };

  GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };

• glClearColor (0.0, 0.0, 0.0, 0.0);glShadeModel (GL_SMOOTH);
• glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);glLightfv(GL_LIGHT0, GL_POSITION, light_position);
• glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);glEnable(GL_DEPTH_TEST);

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glutSolidSphere (1.0, 20, 16);

  glFlush ();

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-1.5, 1.5, -1.5*(GLfloat)h/(GLfloat)w,

  1.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho (-1.5*(GLfloat)w/(GLfloat)h,

  1.5*(GLfloat)w/(GLfloat)h, -1.5, 1.5, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

list.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** list.c* This program demonstrates how to make and execute a

  * display list. Note that attributes, such as current

  * color and matrix, are changed.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• GLuint listName;
• static void init (void){listName = glGenLists (1);

  glNewList (listName, GL_COMPILE);

  glColor3f (1.0, 0.0, 0.0); /* current color red */

  glBegin (GL_TRIANGLES);

  glVertex2f (0.0, 0.0);

  glVertex2f (1.0, 0.0);

  glVertex2f (0.0, 1.0);

  glEnd ();

  glTranslatef (1.5, 0.0, 0.0); /* move position */

  glEndList ();

  glShadeModel (GL_FLAT);

  }

• static void drawLine (void){glBegin (GL_LINES);

  glVertex2f (0.0, 0.5);

  glVertex2f (15.0, 0.5);

  glEnd ();

  }

• void display(void){GLuint i;
• glClear (GL_COLOR_BUFFER_BIT);glColor3f (0.0, 1.0, 0.0); /* current color green */for (i = 0; i < 10; i++) /* draw 10 triangles */

  glCallList (listName);

  drawLine (); /* is this line green? NO! */

  /* where is the line drawn? */

  glFlush ();

  }

• void reshape(int w, int h){glViewport(0, 0, w, h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  gluOrtho2D (0.0, 2.0, -0.5 * (GLfloat) h/(GLfloat) w,

  1.5 * (GLfloat) h/(GLfloat) w);

  else

  gluOrtho2D (0.0, 2.0 * (GLfloat) w/(GLfloat) h, -0.5, 1.5);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize(650, 50);

  glutCreateWindow(argv[0]);

  init ();

  glutReshapeFunc (reshape);

  glutDisplayFunc (display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

material.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** material.c* This program demonstrates the use of the GL lighting model.

  * Several objects are drawn using different material characteristics.

  * A single light source illuminates the objects.

  */

  #include <stdlib.h>

  #include <GL/glut.h>

• /* Initialize z-buffer, projection matrix, light source,* and lighting model. Do not specify a material property here.*/

  void init(void)

  {

  GLfloat ambient[] = { 0.0, 0.0, 0.0, 1.0 };

  GLfloat diffuse[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat position[] = { 0.0, 3.0, 2.0, 0.0 };

  GLfloat lmodel_ambient[] = { 0.4, 0.4, 0.4, 1.0 };

  GLfloat local_view[] = { 0.0 };

• glClearColor(0.0, 0.1, 0.1, 0.0);glEnable(GL_DEPTH_TEST);glShadeModel(GL_SMOOTH);
• glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);glLightfv(GL_LIGHT0, GL_POSITION, position);

  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);

  glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, local_view);

• glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);}
• /* Draw twelve spheres in 3 rows with 4 columns.* The spheres in the first row have materials with no ambient reflection.* The second row has materials with significant ambient reflection.

  * The third row has materials with colored ambient reflection.

  *

  * The first column has materials with blue, diffuse reflection only.

  * The second column has blue diffuse reflection, as well as specular

  * reflection with a low shininess exponent.

  * The third column has blue diffuse reflection, as well as specular

  * reflection with a high shininess exponent (a more concentrated highlight).

  * The fourth column has materials which also include an emissive component.

  *

  * glTranslatef() is used to move spheres to their appropriate locations.

  */

• void display(void){GLfloat no_mat[] = { 0.0, 0.0, 0.0, 1.0 };

  GLfloat mat_ambient[] = { 0.7, 0.7, 0.7, 1.0 };

  GLfloat mat_ambient_color[] = { 0.8, 0.8, 0.2, 1.0 };

  GLfloat mat_diffuse[] = { 0.1, 0.5, 0.8, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat no_shininess[] = { 0.0 };

  GLfloat low_shininess[] = { 5.0 };

  GLfloat high_shininess[] = { 100.0 };

  GLfloat mat_emission[] = {0.3, 0.2, 0.2, 0.0};

• glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
• /* draw sphere in first row, first column* diffuse reflection only; no ambient or specular*/

  glPushMatrix();

  glTranslatef (-3.75, 3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in first row, second column* diffuse and specular reflection; low shininess; no ambient*/

  glPushMatrix();

  glTranslatef (-1.25, 3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in first row, third column* diffuse and specular reflection; high shininess; no ambient*/

  glPushMatrix();

  glTranslatef (1.25, 3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in first row, fourth column* diffuse reflection; emission; no ambient or specular reflection*/

  glPushMatrix();

  glTranslatef (3.75, 3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in second row, first column* ambient and diffuse reflection; no specular*/

  glPushMatrix();

  glTranslatef (-3.75, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in second row, second column* ambient, diffuse and specular reflection; low shininess*/

  glPushMatrix();

  glTranslatef (-1.25, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in second row, third column* ambient, diffuse and specular reflection; high shininess*/

  glPushMatrix();

  glTranslatef (1.25, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in second row, fourth column* ambient and diffuse reflection; emission; no specular*/

  glPushMatrix();

  glTranslatef (3.75, 0.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in third row, first column* colored ambient and diffuse reflection; no specular*/

  glPushMatrix();

  glTranslatef (-3.75, -3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in third row, second column* colored ambient, diffuse and specular reflection; low shininess*/

  glPushMatrix();

  glTranslatef (-1.25, -3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in third row, third column* colored ambient, diffuse and specular reflection; high shininess*/

  glPushMatrix();

  glTranslatef (1.25, -3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• /* draw sphere in third row, fourth column* colored ambient and diffuse reflection; emission; no specular*/

  glPushMatrix();

  glTranslatef (3.75, -3.0, 0.0);

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);

  glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);

  glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);

  glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);

  glutSolidSphere(1.0, 16, 16);

  glPopMatrix();

• glFlush();}
• void reshape(int w, int h){glViewport(0, 0, w, h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= (h * 2))

  glOrtho (-6.0, 6.0, -3.0*((GLfloat)h*2)/(GLfloat)w,

  3.0*((GLfloat)h*2)/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho (-6.0*(GLfloat)w/((GLfloat)h*2),

  6.0*(GLfloat)w/((GLfloat)h*2), -3.0, 3.0, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (600, 450);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

mipmap.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* mipmap.c* This program demonstrates using mipmaps for texture maps.* To overtly show the effect of mipmaps, each mipmap reduction

  * level has a solidly colored, contrasting texture image.

  * Thus, the quadrilateral which is drawn is drawn with several

  * different colors.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• GLubyte mipmapImage32[32][32][4];GLubyte mipmapImage16[16][16][4];GLubyte mipmapImage8[8][8][4];

  GLubyte mipmapImage4[4][4][4];

  GLubyte mipmapImage2[2][2][4];

  GLubyte mipmapImage1[1][1][4];

• #ifdef GL_VERSION_1_1static GLuint texName;#endif
• void makeImages(void){int i, j;for (i = 0; i < 32; i++) {

  for (j = 0; j < 32; j++) {

  mipmapImage32[i][j][0] = 255;

  mipmapImage32[i][j][1] = 255;

  mipmapImage32[i][j][2] = 0;

  mipmapImage32[i][j][3] = 255;

  }

  }

  for (i = 0; i < 16; i++) {

  for (j = 0; j < 16; j++) {

  mipmapImage16[i][j][0] = 255;

  mipmapImage16[i][j][1] = 0;

  mipmapImage16[i][j][2] = 255;

  mipmapImage16[i][j][3] = 255;

  }

  }

  for (i = 0; i < 8; i++) {

  for (j = 0; j < 8; j++) {

  mipmapImage8[i][j][0] = 255;

  mipmapImage8[i][j][1] = 0;

  mipmapImage8[i][j][2] = 0;

  mipmapImage8[i][j][3] = 255;

  }

  }

  for (i = 0; i < 4; i++) {

  for (j = 0; j < 4; j++) {

  mipmapImage4[i][j][0] = 0;

  mipmapImage4[i][j][1] = 255;

  mipmapImage4[i][j][2] = 0;

  mipmapImage4[i][j][3] = 255;

  }

  }

  for (i = 0; i < 2; i++) {

  for (j = 0; j < 2; j++) {

  mipmapImage2[i][j][0] = 0;

  mipmapImage2[i][j][1] = 0;

  mipmapImage2[i][j][2] = 255;

  mipmapImage2[i][j][3] = 255;

  }

  }

  mipmapImage1[0][0][0] = 255;

  mipmapImage1[0][0][1] = 255;

  mipmapImage1[0][0][2] = 255;

  mipmapImage1[0][0][3] = 255;

  }

• void init(void){glEnable(GL_DEPTH_TEST);

  glShadeModel(GL_FLAT);

• glTranslatef(0.0, 0.0, -3.6);makeImages();glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
• #ifdef GL_VERSION_1_1glGenTextures(1, &texName);glBindTexture(GL_TEXTURE_2D, texName);

  #endif

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,

  GL_NEAREST_MIPMAP_NEAREST);

  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 32, 32, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage32);

  glTexImage2D(GL_TEXTURE_2D, 1, GL_RGBA, 16, 16, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage16);

  glTexImage2D(GL_TEXTURE_2D, 2, GL_RGBA, 8, 8, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage8);

  glTexImage2D(GL_TEXTURE_2D, 3, GL_RGBA, 4, 4, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage4);

  glTexImage2D(GL_TEXTURE_2D, 4, GL_RGBA, 2, 2, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage2);

  glTexImage2D(GL_TEXTURE_2D, 5, GL_RGBA, 1, 1, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage1);

• glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);glEnable(GL_TEXTURE_2D);}
• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  #ifdef GL_VERSION_1_1

  glBindTexture(GL_TEXTURE_2D, texName);

  #endif

  glBegin(GL_QUADS);

  glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -1.0, 0.0);

  glTexCoord2f(0.0, 8.0); glVertex3f(-2.0, 1.0, 0.0);

  glTexCoord2f(8.0, 8.0); glVertex3f(2000.0, 1.0, -6000.0);

  glTexCoord2f(8.0, 0.0); glVertex3f(2000.0, -1.0, -6000.0);

  glEnd();

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluPerspective(60.0, (GLfloat)w/(GLfloat)h, 1.0, 30000.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard (unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (50, 50);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

model.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** model.c* This program demonstrates modeling transformations

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_FLAT);

  }

• void draw_triangle(void){glBegin (GL_LINE_LOOP);

  glVertex2f(0.0, 25.0);

  glVertex2f(25.0, -25.0);

  glVertex2f(-25.0, -25.0);

  glEnd();

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT);

  glColor3f (1.0, 1.0, 1.0);

• glLoadIdentity ();glColor3f (1.0, 1.0, 1.0);draw_triangle ();
• glEnable (GL_LINE_STIPPLE);glLineStipple (1, 0xF0F0);glLoadIdentity ();

  glTranslatef (-20.0, 0.0, 0.0);

  draw_triangle ();

• glLineStipple (1, 0xF00F);glLoadIdentity ();glScalef (1.5, 0.5, 1.0);

  draw_triangle ();

• glLineStipple (1, 0x8888);glLoadIdentity ();glRotatef (90.0, 0.0, 0.0, 1.0);

  draw_triangle ();

  glDisable (GL_LINE_STIPPLE);

• glFlush ();}
• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  if (w <= h)

  glOrtho (-50.0, 50.0, -50.0*(GLfloat)h/(GLfloat)w,

  50.0*(GLfloat)h/(GLfloat)w, -1.0, 1.0);

  else

  glOrtho (-50.0*(GLfloat)w/(GLfloat)h,

  50.0*(GLfloat)w/(GLfloat)h, -50.0, 50.0, -1.0, 1.0);

  glMatrixMode(GL_MODELVIEW);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

pickdepth.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** pickdepth.c* Picking is demonstrated in this program. In

  * rendering mode, three overlapping rectangles are

  * drawn. When the left mouse button is pressed,

  * selection mode is entered with the picking matrix.

  * Rectangles which are drawn under the cursor position

  * are “picked.” Pay special attention to the depth

  * value range, which is returned.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• void init(void){glClearColor(0.0, 0.0, 0.0, 0.0);

  glEnable(GL_DEPTH_TEST);

  glShadeModel(GL_FLAT);

  glDepthRange(0.0, 1.0); /* The default z mapping */

  }

• /* The three rectangles are drawn. In selection mode,* each rectangle is given the same name. Note that* each rectangle is drawn with a different z value.

  */

  void drawRects(GLenum mode)

  {

  if (mode == GL_SELECT)

  glLoadName(1);

  glBegin(GL_QUADS);

  glColor3f(1.0, 1.0, 0.0);

  glVertex3i(2, 0, 0);

  glVertex3i(2, 6, 0);

  glVertex3i(6, 6, 0);

  glVertex3i(6, 0, 0);

  glEnd();

  if (mode == GL_SELECT)

  glLoadName(2);

  glBegin(GL_QUADS);

  glColor3f(0.0, 1.0, 1.0);

  glVertex3i(3, 2, -1);

  glVertex3i(3, 8, -1);

  glVertex3i(8, 8, -1);

  glVertex3i(8, 2, -1);

  glEnd();

  if (mode == GL_SELECT)

  glLoadName(3);

  glBegin(GL_QUADS);

  glColor3f(1.0, 0.0, 1.0);

  glVertex3i(0, 2, -2);

  glVertex3i(0, 7, -2);

  glVertex3i(5, 7, -2);

  glVertex3i(5, 2, -2);

  glEnd();

  }

• /* processHits() prints out the contents of the* selection array.*/

  void processHits(GLint hits, GLuint buffer[])

  {

  unsigned int i, j;

  GLuint names, *ptr;

• printf(“hits = %d\n”, hits);ptr = (GLuint *) buffer;for (i = 0; i < hits; i++) { /* for each hit */

  names = *ptr;

  printf(” number of names for hit = %d\n”, names); ptr++;

  printf(” z1 is %g;”, (float) *ptr/0x7fffffff); ptr++;

  printf(” z2 is %g\n”, (float) *ptr/0x7fffffff); ptr++;

  printf(” the name is “);

  for (j = 0; j < names; j++) { /* for each name */

  printf(“%d “, *ptr); ptr++;

  }

  printf(“\n”);

  }

  }

• /* pickRects() sets up selection mode, name stack,* and projection matrix for picking. Then the objects* are drawn.

  */

  #define BUFSIZE 512

• void pickRects(int button, int state, int x, int y){GLuint selectBuf[BUFSIZE];

  GLint hits;

  GLint viewport[4];

• if (button != GLUT_LEFT_BUTTON || state != GLUT_DOWN)return;
• glGetIntegerv(GL_VIEWPORT, viewport);
• glSelectBuffer(BUFSIZE, selectBuf);(void) glRenderMode(GL_SELECT);
• glInitNames();glPushName(0);
• glMatrixMode(GL_PROJECTION);glPushMatrix();glLoadIdentity();

  /* create 5×5 pixel picking region near cursor location */

  gluPickMatrix((GLdouble) x, (GLdouble) (viewport[3] – y),

  5.0, 5.0, viewport);

  glOrtho(0.0, 8.0, 0.0, 8.0, -0.5, 2.5);

  drawRects(GL_SELECT);

  glPopMatrix();

  glFlush();

• hits = glRenderMode(GL_RENDER);processHits(hits, selectBuf);}
• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  drawRects(GL_RENDER);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  glOrtho(0.0, 8.0, 0.0, 8.0, -0.5, 2.5);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop*/int main(int argc, char **argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (200, 200);

  glutInitWindowPosition (100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutMouseFunc(pickRects);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

picksquare.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** picksquare.c* Use of multiple names and picking are demonstrated.

  * A 3×3 grid of squares is drawn. When the left mouse

  * button is pressed, all squares under the cursor position

  * have their color changed.

  */

  #include <stdlib.h>

  #include <stdio.h>

  #include <GL/glut.h>

• int board[3][3]; /* amount of color for each square */
• /* Clear color value for every square on the board */void init(void){

  int i, j;

  for (i = 0; i < 3; i++)

  for (j = 0; j < 3; j ++)

  board[i][j] = 0;

  glClearColor (0.0, 0.0, 0.0, 0.0);

  }

• /* The nine squares are drawn. In selection mode, each* square is given two names: one for the row and the* other for the column on the grid. The color of each

  * square is determined by its position on the grid, and

  * the value in the board[][] array.

  */

  void drawSquares(GLenum mode)

  {

  GLuint i, j;

  for (i = 0; i < 3; i++) {

  if (mode == GL_SELECT)

  glLoadName (i);

  for (j = 0; j < 3; j ++) {

  if (mode == GL_SELECT)

  glPushName (j);

  glColor3f ((GLfloat) i/3.0, (GLfloat) j/3.0,

  (GLfloat) board[i][j]/3.0);

  glRecti (i, j, i+1, j+1);

  if (mode == GL_SELECT)

  glPopName ();

  }

  }

  }

• /* processHits prints out the contents of the* selection array.*/

  void processHits (GLint hits, GLuint buffer[])

  {

  unsigned int i, j;

  GLuint ii, jj, names, *ptr;

• printf (“hits = %d\n”, hits);ptr = (GLuint *) buffer;for (i = 0; i < hits; i++) { /* for each hit */

  names = *ptr;

  printf (” number of names for this hit = %d\n”, names); ptr++;

  printf(” z1 is %g;”, (float) *ptr/0x7fffffff); ptr++;

  printf(” z2 is %g\n”, (float) *ptr/0x7fffffff); ptr++;

  printf (” names are “);

  for (j = 0; j < names; j++) { /* for each name */

  printf (“%d “, *ptr);

  if (j == 0) /* set row and column */

  ii = *ptr;

  else if (j == 1)

  jj = *ptr;

  ptr++;

  }

  printf (“\n”);

  board[ii][jj] = (board[ii][jj] + 1) % 3;

  }

  }

• /* pickSquares() sets up selection mode, name stack,* and projection matrix for picking. Then the* objects are drawn.

  */

  #define BUFSIZE 512

• void pickSquares(int button, int state, int x, int y){GLuint selectBuf[BUFSIZE];

  GLint hits;

  GLint viewport[4];

• if (button != GLUT_LEFT_BUTTON || state != GLUT_DOWN)return;
• glGetIntegerv (GL_VIEWPORT, viewport);
• glSelectBuffer (BUFSIZE, selectBuf);(void) glRenderMode (GL_SELECT);
• glInitNames();glPushName(0);
• glMatrixMode (GL_PROJECTION);glPushMatrix ();glLoadIdentity ();

  /* create 5×5 pixel picking region near cursor location */

  gluPickMatrix ((GLdouble) x, (GLdouble) (viewport[3] – y),

  5.0, 5.0, viewport);

  gluOrtho2D (0.0, 3.0, 0.0, 3.0);

  drawSquares (GL_SELECT);

• glMatrixMode (GL_PROJECTION);glPopMatrix ();glFlush ();
• hits = glRenderMode (GL_RENDER);processHits (hits, selectBuf);glutPostRedisplay();

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT);

  drawSquares (GL_RENDER);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, w, h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluOrtho2D (0.0, 3.0, 0.0, 3.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop */int main(int argc, char** argv){

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (100, 100);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutReshapeFunc (reshape);

  glutDisplayFunc(display);

  glutMouseFunc (pickSquares);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

planet.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** planet.c* This program shows how to composite modeling transformations

  * to draw translated and rotated models.

  * Interaction: pressing the d and y keys (day and year)

  * alters the rotation of the planet around the sun.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• static int year = 0, day = 0;
• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_FLAT);

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT);

  glColor3f (1.0, 1.0, 1.0);

• glPushMatrix();glutWireSphere(1.0, 20, 16); /* draw sun */glRotatef ((GLfloat) year, 0.0, 1.0, 0.0);

  glTranslatef (2.0, 0.0, 0.0);

  glRotatef ((GLfloat) day, 0.0, 1.0, 0.0);

  glutWireSphere(0.2, 10, 8); /* draw smaller planet */

  glPopMatrix();

  glutSwapBuffers();

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

  }

• void keyboard (unsigned char key, int x, int y){switch (key) {

  case ‘d’:

  day = (day + 10) % 360;

  glutPostRedisplay();

  break;

  case ‘D’:

  day = (day – 10) % 360;

  glutPostRedisplay();

  break;

  case ‘y’:

  year = (year + 5) % 360;

  glutPostRedisplay();

  break;

  case ‘Y’:

  year = (year – 5) % 360;

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

polyoff.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** polyoff.c* This program demonstrates polygon offset to draw a shaded

  * polygon and its wireframe counterpart without ugly visual

  * artifacts (“stitching”).

  */

  #include <GL/glut.h>

  #include <stdio.h>

  #include <stdlib.h>

• #ifdef GL_VERSION_1_1GLuint list;GLint spinx = 0;

  GLint spiny = 0;

  GLfloat tdist = 0.0;

  GLfloat polyfactor = 1.0;

  GLfloat polyunits = 1.0;

• /* display() draws two spheres, one with a gray, diffuse material,* the other sphere with a magenta material with a specular highlight.*/

  void display (void)

  {

  GLfloat mat_ambient[] = { 0.8, 0.8, 0.8, 1.0 };

  GLfloat mat_diffuse[] = { 1.0, 0.0, 0.5, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat gray[] = { 0.8, 0.8, 0.8, 1.0 };

  GLfloat black[] = { 0.0, 0.0, 0.0, 1.0 };

• glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);glPushMatrix ();glTranslatef (0.0, 0.0, tdist);

  glRotatef ((GLfloat) spinx, 1.0, 0.0, 0.0);

  glRotatef ((GLfloat) spiny, 0.0, 1.0, 0.0);

• glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, gray);glMaterialfv(GL_FRONT, GL_SPECULAR, black);glMaterialf(GL_FRONT, GL_SHININESS, 0.0);

  glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

  glEnable(GL_POLYGON_OFFSET_FILL);

  glPolygonOffset(polyfactor, polyunits);

  glCallList (list);

  glDisable(GL_POLYGON_OFFSET_FILL);

• glDisable(GL_LIGHTING);glDisable(GL_LIGHT0);glColor3f (1.0, 1.0, 1.0);

  glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);

  glCallList (list);

  glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);

• glPopMatrix ();glFlush ();}
• /* specify initial properties* create display list with sphere* initialize lighting and depth buffer

  */

  void gfxinit (void)

  {

  GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 };

  GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };

• GLfloat global_ambient[] = { 0.2, 0.2, 0.2, 1.0 };
• glClearColor (0.0, 0.0, 0.0, 1.0);
• list = glGenLists(1);glNewList (list, GL_COMPILE);glutSolidSphere(1.0, 20, 12);

  glEndList ();

• glEnable(GL_DEPTH_TEST);
• glLightfv (GL_LIGHT0, GL_AMBIENT, light_ambient);glLightfv (GL_LIGHT0, GL_DIFFUSE, light_diffuse);glLightfv (GL_LIGHT0, GL_SPECULAR, light_specular);

  glLightfv (GL_LIGHT0, GL_POSITION, light_position);

  glLightModelfv (GL_LIGHT_MODEL_AMBIENT, global_ambient);

  }

• /* call when window is resized */void reshape(int width, int height){

  glViewport (0, 0, width, height);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluPerspective(45.0, (GLdouble)width/(GLdouble)height,

  1.0, 10.0);

  glMatrixMode (GL_MODELVIEW);

  glLoadIdentity ();

  gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

  }

• /* call when mouse button is pressed */void mouse(int button, int state, int x, int y) {switch (button) {

  case GLUT_LEFT_BUTTON:

  switch (state) {

  case GLUT_DOWN:

  spinx = (spinx + 5) % 360;

  glutPostRedisplay();

  break;

  default:

  break;

  }

  break;

  case GLUT_MIDDLE_BUTTON:

  switch (state) {

  case GLUT_DOWN:

  spiny = (spiny + 5) % 360;

  glutPostRedisplay();

  break;

  default:

  break;

  }

  break;

  case GLUT_RIGHT_BUTTON:

  switch (state) {

  case GLUT_UP:

  exit(0);

  break;

  default:

  break;

  }

  break;

  default:

  break;

  }

  }

• void keyboard (unsigned char key, int x, int y){switch (key) {

  case ‘t’:

  if (tdist < 4.0) {

  tdist = (tdist + 0.5);

  glutPostRedisplay();

  }

  break;

  case ‘T’:

  if (tdist > -5.0) {

  tdist = (tdist – 0.5);

  glutPostRedisplay();

  }

  break;

  case ‘F’:

  polyfactor = polyfactor + 0.1;

  printf (“polyfactor is %f\n”, polyfactor);

  glutPostRedisplay();

  break;

  case ‘f’:

  polyfactor = polyfactor – 0.1;

  printf (“polyfactor is %f\n”, polyfactor);

  glutPostRedisplay();

  break;

  case ‘U’:

  polyunits = polyunits + 1.0;

  printf (“polyunits is %f\n”, polyunits);

  glutPostRedisplay();

  break;

  case ‘u’:

  polyunits = polyunits – 1.0;

  printf (“polyunits is %f\n”, polyunits);

  glutPostRedisplay();

  break;

  default:

  break;

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutCreateWindow(argv[0]);

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutMouseFunc(mouse);

  glutKeyboardFunc(keyboard);

  gfxinit();

  glutMainLoop();

  return 0;

  }

  #else

  int main(int argc, char** argv)

  {

  fprintf (stderr, “This program demonstrates a feature which is not in OpenGL Version 1.0.\n”);

  fprintf (stderr, “If your implementation of OpenGL Version 1.0 has the right extensions,\n”);

  fprintf (stderr, “you may be able to modify this program to make it run.\n”);

  return 0;

  }

  #endif

polys.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** polys.c* This program demonstrates polygon stippling.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• void display(void){GLubyte fly[] = {

  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

  0x03, 0x80, 0x01, 0xC0, 0x06, 0xC0, 0x03, 0x60,

  0x04, 0x60, 0x06, 0x20, 0x04, 0x30, 0x0C, 0x20,

  0x04, 0x18, 0x18, 0x20, 0x04, 0x0C, 0x30, 0x20,

  0x04, 0x06, 0x60, 0x20, 0x44, 0x03, 0xC0, 0x22,

  0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,

  0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,

  0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,

  0x66, 0x01, 0x80, 0x66, 0x33, 0x01, 0x80, 0xCC,

  0x19, 0x81, 0x81, 0x98, 0x0C, 0xC1, 0x83, 0x30,

  0x07, 0xe1, 0x87, 0xe0, 0x03, 0x3f, 0xfc, 0xc0,

  0x03, 0x31, 0x8c, 0xc0, 0x03, 0x33, 0xcc, 0xc0,

  0x06, 0x64, 0x26, 0x60, 0x0c, 0xcc, 0x33, 0x30,

  0x18, 0xcc, 0x33, 0x18, 0x10, 0xc4, 0x23, 0x08,

  0x10, 0x63, 0xC6, 0x08, 0x10, 0x30, 0x0c, 0x08,

  0x10, 0x18, 0x18, 0x08, 0x10, 0x00, 0x00, 0x08};

• GLubyte halftone[] = {0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

  0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55};

• glClear (GL_COLOR_BUFFER_BIT);glColor3f (1.0, 1.0, 1.0);
• /* draw one solid, unstippled rectangle, *//* then two stippled rectangles */glRectf (25.0, 25.0, 125.0, 125.0);

  glEnable (GL_POLYGON_STIPPLE);

  glPolygonStipple (fly);

  glRectf (125.0, 25.0, 225.0, 125.0);

  glPolygonStipple (halftone);

  glRectf (225.0, 25.0, 325.0, 125.0);

  glDisable (GL_POLYGON_STIPPLE);

• glFlush ();}
• void init (void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_FLAT);

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluOrtho2D (0.0, (GLdouble) w, 0.0, (GLdouble) h);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (350, 150);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

quadric.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** quadric.c* This program demonstrates the use of some of the gluQuadric*

  * routines. Quadric objects are created with some quadric

  * properties and the callback routine to handle errors.

  * Note that the cylinder has no top or bottom and the circle

  * has a hole in it.

  */

  #include <GL/glut.h>

  #include <stdio.h>

  #include <stdlib.h>

• #ifndef CALLBACK#define CALLBACK#endif
• GLuint startList;
• void CALLBACK errorCallback(GLenum errorCode){const GLubyte *estring;
• estring = gluErrorString(errorCode);fprintf(stderr, “Quadric Error: %s\n”, estring);exit(0);

  }

• void init(void){GLUquadricObj *qobj;

  GLfloat mat_ambient[] = { 0.5, 0.5, 0.5, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat mat_shininess[] = { 50.0 };

  GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };

  GLfloat model_ambient[] = { 0.5, 0.5, 0.5, 1.0 };

• glClearColor(0.0, 0.0, 0.0, 0.0);
• glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);

  glLightfv(GL_LIGHT0, GL_POSITION, light_position);

  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, model_ambient);

• glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);glEnable(GL_DEPTH_TEST);
• /* Create 4 display lists, each with a different quadric object.* Different drawing styles and surface normal specifications* are demonstrated.

  */

  startList = glGenLists(4);

  qobj = gluNewQuadric();

  gluQuadricCallback(qobj, GLU_ERROR,

  errorCallback);

• gluQuadricDrawStyle(qobj, GLU_FILL); /* smooth shaded */gluQuadricNormals(qobj, GLU_SMOOTH);glNewList(startList, GL_COMPILE);

  gluSphere(qobj, 0.75, 15, 10);

  glEndList();

• gluQuadricDrawStyle(qobj, GLU_FILL); /* flat shaded */gluQuadricNormals(qobj, GLU_FLAT);glNewList(startList+1, GL_COMPILE);

  gluCylinder(qobj, 0.5, 0.3, 1.0, 15, 5);

  glEndList();

• gluQuadricDrawStyle(qobj, GLU_LINE); /* all polygons wireframe */gluQuadricNormals(qobj, GLU_NONE);glNewList(startList+2, GL_COMPILE);

  gluDisk(qobj, 0.25, 1.0, 20, 4);

  glEndList();

• gluQuadricDrawStyle(qobj, GLU_SILHOUETTE); /* boundary only */gluQuadricNormals(qobj, GLU_NONE);glNewList(startList+3, GL_COMPILE);

  gluPartialDisk(qobj, 0.0, 1.0, 20, 4, 0.0, 225.0);

  glEndList();

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glPushMatrix();

• glEnable(GL_LIGHTING);glShadeModel (GL_SMOOTH);glTranslatef(-1.0, -1.0, 0.0);

  glCallList(startList);

• glShadeModel (GL_FLAT);glTranslatef(0.0, 2.0, 0.0);glPushMatrix();

  glRotatef(300.0, 1.0, 0.0, 0.0);

  glCallList(startList+1);

  glPopMatrix();

• glDisable(GL_LIGHTING);glColor3f(0.0, 1.0, 1.0);glTranslatef(2.0, -2.0, 0.0);

  glCallList(startList+2);

• glColor3f(1.0, 1.0, 0.0);glTranslatef(0.0, 2.0, 0.0);glCallList(startList+3);
• glPopMatrix();glFlush();}
• void reshape (int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho(-2.5, 2.5, -2.5*(GLfloat)h/(GLfloat)w,

  2.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);

  else

  glOrtho(-2.5*(GLfloat)w/(GLfloat)h,

  2.5*(GLfloat)w/(GLfloat)h, -2.5, 2.5, -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize(500, 500);

  glutInitWindowPosition(100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

robot.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** robot.c* This program shows how to composite modeling transformations

  * to draw translated and rotated hierarchical models.

  * Interaction: pressing the s and e keys (shoulder and elbow)

  * alters the rotation of the robot arm.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• static int shoulder = 0, elbow = 0;
• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_FLAT);

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT);

  glPushMatrix();

  glTranslatef (-1.0, 0.0, 0.0);

  glRotatef ((GLfloat) shoulder, 0.0, 0.0, 1.0);

  glTranslatef (1.0, 0.0, 0.0);

  glPushMatrix();

  glScalef (2.0, 0.4, 1.0);

  glutWireCube (1.0);

  glPopMatrix();

• glTranslatef (1.0, 0.0, 0.0);glRotatef ((GLfloat) elbow, 0.0, 0.0, 1.0);glTranslatef (1.0, 0.0, 0.0);

  glPushMatrix();

  glScalef (2.0, 0.4, 1.0);

  glutWireCube (1.0);

  glPopMatrix();

• glPopMatrix();glutSwapBuffers();}
• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluPerspective(65.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  glTranslatef (0.0, 0.0, -5.0);

  }

• void keyboard (unsigned char key, int x, int y){switch (key) {

  case ‘s’:

  shoulder = (shoulder + 5) % 360;

  glutPostRedisplay();

  break;

  case ‘S’:

  shoulder = (shoulder – 5) % 360;

  glutPostRedisplay();

  break;

  case ‘e’:

  elbow = (elbow + 5) % 360;

  glutPostRedisplay();

  break;

  case ‘E’:

  elbow = (elbow – 5) % 360;

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

select.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** select.c* This is an illustration of the selection mode and

  * name stack, which detects whether objects which collide

  * with a viewing volume. First, four triangles and a

  * rectangular box representing a viewing volume are drawn

  * (drawScene routine). The green triangle and yellow

  * triangles appear to lie within the viewing volume, but

  * the red triangle appears to lie outside it. Then the

  * selection mode is entered (selectObjects routine).

  * Drawing to the screen ceases. To see if any collisions

  * occur, the four triangles are called. In this example,

  * the green triangle causes one hit with the name 1, and

  * the yellow triangles cause one hit with the name 3.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• /* draw a triangle with vertices at (x1, y1), (x2, y2)* and (x3, y3) at z units away from the origin.*/

  void drawTriangle (GLfloat x1, GLfloat y1, GLfloat x2,

  GLfloat y2, GLfloat x3, GLfloat y3, GLfloat z)

  {

  glBegin (GL_TRIANGLES);

  glVertex3f (x1, y1, z);

  glVertex3f (x2, y2, z);

  glVertex3f (x3, y3, z);

  glEnd ();

  }

• /* draw a rectangular box with these outer x, y, and z values */void drawViewVolume (GLfloat x1, GLfloat x2, GLfloat y1,GLfloat y2, GLfloat z1, GLfloat z2)

  {

  glColor3f (1.0, 1.0, 1.0);

  glBegin (GL_LINE_LOOP);

  glVertex3f (x1, y1, -z1);

  glVertex3f (x2, y1, -z1);

  glVertex3f (x2, y2, -z1);

  glVertex3f (x1, y2, -z1);

  glEnd ();

• glBegin (GL_LINE_LOOP);glVertex3f (x1, y1, -z2);glVertex3f (x2, y1, -z2);

  glVertex3f (x2, y2, -z2);

  glVertex3f (x1, y2, -z2);

  glEnd ();

• glBegin (GL_LINES); /* 4 lines */glVertex3f (x1, y1, -z1);glVertex3f (x1, y1, -z2);

  glVertex3f (x1, y2, -z1);

  glVertex3f (x1, y2, -z2);

  glVertex3f (x2, y1, -z1);

  glVertex3f (x2, y1, -z2);

  glVertex3f (x2, y2, -z1);

  glVertex3f (x2, y2, -z2);

  glEnd ();

  }

• /* drawScene draws 4 triangles and a wire frame* which represents the viewing volume.*/

  void drawScene (void)

  {

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluPerspective (40.0, 4.0/3.0, 1.0, 100.0);

• glMatrixMode (GL_MODELVIEW);glLoadIdentity ();gluLookAt (7.5, 7.5, 12.5, 2.5, 2.5, -5.0, 0.0, 1.0, 0.0);
• glColor3f (0.0, 1.0, 0.0); /* green triangle */drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, -5.0);glColor3f (1.0, 0.0, 0.0); /* red triangle */

  drawTriangle (2.0, 7.0, 3.0, 7.0, 2.5, 8.0, -5.0);

  glColor3f (1.0, 1.0, 0.0); /* yellow triangles */

  drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, 0.0);

  drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, -10.0);

  drawViewVolume (0.0, 5.0, 0.0, 5.0, 0.0, 10.0);

  }

• /* processHits prints out the contents of the selection array*/void processHits (GLint hits, GLuint buffer[])

  {

  unsigned int i, j;

  GLuint names, *ptr;

• printf (“hits = %d\n”, hits);ptr = (GLuint *) buffer;for (i = 0; i < hits; i++) { /* for each hit */

  names = *ptr;

  printf (” number of names for hit = %d\n”, names); ptr++;

  printf(” z1 is %g;”, (float) *ptr/0x7fffffff); ptr++;

  printf(” z2 is %g\n”, (float) *ptr/0x7fffffff); ptr++;

  printf (” the name is “);

  for (j = 0; j < names; j++) { /* for each name */

  printf (“%d “, *ptr); ptr++;

  }

  printf (“\n”);

  }

  }

• /* selectObjects “draws” the triangles in selection mode,* assigning names for the triangles. Note that the third* and fourth triangles share one name, so that if either

  * or both triangles intersects the viewing/clipping volume,

  * only one hit will be registered.

  */

  #define BUFSIZE 512

• void selectObjects(void){GLuint selectBuf[BUFSIZE];

  GLint hits;

• glSelectBuffer (BUFSIZE, selectBuf);(void) glRenderMode (GL_SELECT);
• glInitNames();glPushName(0);
• glPushMatrix ();glMatrixMode (GL_PROJECTION);glLoadIdentity ();

  glOrtho (0.0, 5.0, 0.0, 5.0, 0.0, 10.0);

  glMatrixMode (GL_MODELVIEW);

  glLoadIdentity ();

  glLoadName(1);

  drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, -5.0);

  glLoadName(2);

  drawTriangle (2.0, 7.0, 3.0, 7.0, 2.5, 8.0, -5.0);

  glLoadName(3);

  drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, 0.0);

  drawTriangle (2.0, 2.0, 3.0, 2.0, 2.5, 3.0, -10.0);

  glPopMatrix ();

  glFlush ();

• hits = glRenderMode (GL_RENDER);processHits (hits, selectBuf);}
• void init (void){glEnable(GL_DEPTH_TEST);

  glShadeModel(GL_FLAT);

  }

• void display(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  drawScene ();

  selectObjects ();

  glFlush();

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /* Main Loop */int main(int argc, char** argv){

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (200, 200);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init();

  glutDisplayFunc(display);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

smooth.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** smooth.c* This program demonstrates smooth shading.

  * A smooth shaded polygon is drawn in a 2-D projection.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel (GL_SMOOTH);

  }

• void triangle(void){glBegin (GL_TRIANGLES);

  glColor3f (1.0, 0.0, 0.0);

  glVertex2f (5.0, 5.0);

  glColor3f (0.0, 1.0, 0.0);

  glVertex2f (25.0, 5.0);

  glColor3f (0.0, 0.0, 1.0);

  glVertex2f (5.0, 25.0);

  glEnd();

  }

• void display(void){glClear (GL_COLOR_BUFFER_BIT);

  triangle ();

  glFlush ();

  }

• void reshape (int w, int h){glViewport (0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  if (w <= h)

  gluOrtho2D (0.0, 30.0, 0.0, 30.0 * (GLfloat) h/(GLfloat) w);

  else

  gluOrtho2D (0.0, 30.0 * (GLfloat) w/(GLfloat) h, 0.0, 30.0);

  glMatrixMode(GL_MODELVIEW);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

stroke.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** stroke.c* This program demonstrates some characters of a

  * stroke (vector) font. The characters are represented

  * by display lists, which are given numbers which

  * correspond to the ASCII values of the characters.

  * Use of glCallLists() is demonstrated.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <string.h>

• #define PT 1#define STROKE 2#define END 3
• typedef struct charpoint {GLfloat x, y;int type;

  } CP;

• CP Adata[] = {{ 0, 0, PT}, {0, 9, PT}, {1, 10, PT}, {4, 10, PT},{5, 9, PT}, {5, 0, STROKE}, {0, 5, PT}, {5, 5, END}

  };

• CP Edata[] = {{5, 0, PT}, {0, 0, PT}, {0, 10, PT}, {5, 10, STROKE},{0, 5, PT}, {4, 5, END}

  };

• CP Pdata[] = {{0, 0, PT}, {0, 10, PT}, {4, 10, PT}, {5, 9, PT}, {5, 6, PT},{4, 5, PT}, {0, 5, END}

  };

• CP Rdata[] = {{0, 0, PT}, {0, 10, PT}, {4, 10, PT}, {5, 9, PT}, {5, 6, PT},{4, 5, PT}, {0, 5, STROKE}, {3, 5, PT}, {5, 0, END}

  };

• CP Sdata[] = {{0, 1, PT}, {1, 0, PT}, {4, 0, PT}, {5, 1, PT}, {5, 4, PT},{4, 5, PT}, {1, 5, PT}, {0, 6, PT}, {0, 9, PT}, {1, 10, PT},

  {4, 10, PT}, {5, 9, END}

  };

• /* drawLetter() interprets the instructions from the array* for that letter and renders the letter with line segments.*/

  static void drawLetter(CP *l)

  {

  glBegin(GL_LINE_STRIP);

  while (1) {

  switch (l->type) {

  case PT:

  glVertex2fv(&l->x);

  break;

  case STROKE:

  glVertex2fv(&l->x);

  glEnd();

  glBegin(GL_LINE_STRIP);

  break;

  case END:

  glVertex2fv(&l->x);

  glEnd();

  glTranslatef(8.0, 0.0, 0.0);

  return;

  }

  l++;

  }

  }

• /* Create a display list for each of 6 characters */static void init (void){

  GLuint base;

• glShadeModel (GL_FLAT);
• base = glGenLists (128);glListBase(base);glNewList(base+’A’, GL_COMPILE); drawLetter(Adata); glEndList();

  glNewList(base+’E’, GL_COMPILE); drawLetter(Edata); glEndList();

  glNewList(base+’P’, GL_COMPILE); drawLetter(Pdata); glEndList();

  glNewList(base+’R’, GL_COMPILE); drawLetter(Rdata); glEndList();

  glNewList(base+’S’, GL_COMPILE); drawLetter(Sdata); glEndList();

  glNewList(base+’ ‘, GL_COMPILE); glTranslatef(8.0, 0.0, 0.0); glEndList();

  }

• char *test1 = “A SPARE SERAPE APPEARS AS”;char *test2 = “APES PREPARE RARE PEPPERS”;
• static void printStrokedString(char *s){GLsizei len = strlen(s);

  glCallLists(len, GL_BYTE, (GLbyte *)s);

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT);

  glColor3f(1.0, 1.0, 1.0);

  glPushMatrix();

  glScalef(2.0, 2.0, 2.0);

  glTranslatef(10.0, 30.0, 0.0);

  printStrokedString(test1);

  glPopMatrix();

  glPushMatrix();

  glScalef(2.0, 2.0, 2.0);

  glTranslatef(10.0, 13.0, 0.0);

  printStrokedString(test2);

  glPopMatrix();

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode (GL_PROJECTION);

  glLoadIdentity ();

  gluOrtho2D (0.0, (GLdouble) w, 0.0, (GLdouble) h);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘ ‘:

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  }

  }

• /* Main Loop* Open window with initial window size, title bar,* RGBA display mode, and handle input events.

  */

  int main(int argc, char** argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize (440, 120);

  glutCreateWindow (“stroke”);

  init ();

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutDisplayFunc(display);

  glutMainLoop();

  return 0;

  }

surface.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** surface.c* This program draws a NURBS surface in the shape of a

  * symmetrical hill. The ‘c’ keyboard key allows you to

  * toggle the visibility of the control points themselves.

  * Note that some of the control points are hidden by the

  * surface itself.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• #ifndef CALLBACK#define CALLBACK#endif
• GLfloat ctlpoints[4][4][3];int showPoints = 0;
• GLUnurbsObj *theNurb;
• /** Initializes the control points of the surface to a small hill.* The control points range from -3 to +3 in x, y, and z

  */

  void init_surface(void)

  {

  int u, v;

  for (u = 0; u < 4; u++) {

  for (v = 0; v < 4; v++) {

  ctlpoints[u][v][0] = 2.0*((GLfloat)u – 1.5);

  ctlpoints[u][v][1] = 2.0*((GLfloat)v – 1.5);

• if ( (u == 1 || u == 2) && (v == 1 || v == 2))ctlpoints[u][v][2] = 3.0;else

  ctlpoints[u][v][2] = -3.0;

  }

  }

  }

• void CALLBACK nurbsError(GLenum errorCode){const GLubyte *estring;
• estring = gluErrorString(errorCode);fprintf (stderr, “Nurbs Error: %s\n”, estring);exit (0);

  }/* Initialize material property and depth buffer.

  */

  void init(void)

  {

  GLfloat mat_diffuse[] = { 0.7, 0.7, 0.7, 1.0 };

  GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

  GLfloat mat_shininess[] = { 100.0 };

• glClearColor (0.0, 0.0, 0.0, 0.0);glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

  glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);

• glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);glEnable(GL_DEPTH_TEST);

  glEnable(GL_AUTO_NORMAL);

  glEnable(GL_NORMALIZE);

• init_surface();
• theNurb = gluNewNurbsRenderer();gluNurbsProperty(theNurb, GLU_SAMPLING_TOLERANCE, 25.0);gluNurbsProperty(theNurb, GLU_DISPLAY_MODE, GLU_FILL);

  gluNurbsCallback(theNurb, GLU_ERROR,

  nurbsError);

  }

• void display(void){GLfloat knots[8] = {0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 1.0};

  int i, j;

• glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
• glPushMatrix();glRotatef(330.0, 1.,0.,0.);glScalef (0.5, 0.5, 0.5);
• gluBeginSurface(theNurb);gluNurbsSurface(theNurb,8, knots, 8, knots,

  4 * 3, 3, &ctlpoints[0][0][0],

  4, 4, GL_MAP2_VERTEX_3);

  gluEndSurface(theNurb);

• if (showPoints) {glPointSize(5.0);glDisable(GL_LIGHTING);

  glColor3f(1.0, 1.0, 0.0);

  glBegin(GL_POINTS);

  for (i = 0; i < 4; i++) {

  for (j = 0; j < 4; j++) {

  glVertex3f(ctlpoints[i][j][0],

  ctlpoints[i][j][1], ctlpoints[i][j][2]);

  }

  }

  glEnd();

  glEnable(GL_LIGHTING);

  }

  glPopMatrix();

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluPerspective (45.0, (GLdouble)w/(GLdouble)h, 3.0, 8.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  glTranslatef (0.0, 0.0, -5.0);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case ‘c’:

  case ‘C’:

  showPoints = !showPoints;

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize (500, 500);

  glutInitWindowPosition (100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

teapots.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** teapots.c* This program demonstrates lots of material properties.

  * A single light source illuminates the objects.

  */

  #include <stdlib.h>

  #include <GL/glut.h>

• GLuint teapotList;
• /** Initialize depth buffer, projection matrix, light source, and lighting* model. Do not specify a material property here.

  */

  void init(void)

  {

  GLfloat ambient[] = {0.0, 0.0, 0.0, 1.0};

  GLfloat diffuse[] = {1.0, 1.0, 1.0, 1.0};

  GLfloat specular[] = {1.0, 1.0, 1.0, 1.0};

  GLfloat position[] = {0.0, 3.0, 3.0, 0.0};

• GLfloat lmodel_ambient[] = {0.2, 0.2, 0.2, 1.0};GLfloat local_view[] = {0.0};
• glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);glLightfv(GL_LIGHT0, GL_POSITION, position);

  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);

  glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, local_view);

• glFrontFace(GL_CW);glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);

  glEnable(GL_AUTO_NORMAL);

  glEnable(GL_NORMALIZE);

  glEnable(GL_DEPTH_TEST);

  /* be efficient–make teapot display list */

  teapotList = glGenLists(1);

  glNewList (teapotList, GL_COMPILE);

  glutSolidTeapot(1.0);

  glEndList ();

  }

• /** Move object into position. Use 3rd through 12th* parameters to specify the material property. Draw a teapot.

  */

  void renderTeapot(GLfloat x, GLfloat y,

  GLfloat ambr, GLfloat ambg, GLfloat ambb,

  GLfloat difr, GLfloat difg, GLfloat difb,

  GLfloat specr, GLfloat specg, GLfloat specb, GLfloat shine)

  {

  GLfloat mat[4];

• glPushMatrix();glTranslatef(x, y, 0.0);mat[0] = ambr; mat[1] = ambg; mat[2] = ambb; mat[3] = 1.0;

  glMaterialfv(GL_FRONT, GL_AMBIENT, mat);

  mat[0] = difr; mat[1] = difg; mat[2] = difb;

  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat);

  mat[0] = specr; mat[1] = specg; mat[2] = specb;

  glMaterialfv(GL_FRONT, GL_SPECULAR, mat);

  glMaterialf(GL_FRONT, GL_SHININESS, shine * 128.0);

  glCallList(teapotList);

  glPopMatrix();

  }

• /*** First column: emerald, jade, obsidian, pearl, ruby, turquoise* 2nd column: brass, bronze, chrome, copper, gold, silver

  * 3rd column: black, cyan, green, red, white, yellow plastic

  * 4th column: black, cyan, green, red, white, yellow rubber

  */

  void display(void)

  {

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  renderTeapot(2.0, 17.0, 0.0215, 0.1745, 0.0215,

  0.07568, 0.61424, 0.07568, 0.633, 0.727811, 0.633, 0.6);

  renderTeapot(2.0, 14.0, 0.135, 0.2225, 0.1575,

  0.54, 0.89, 0.63, 0.316228, 0.316228, 0.316228, 0.1);

  renderTeapot(2.0, 11.0, 0.05375, 0.05, 0.06625,

  0.18275, 0.17, 0.22525, 0.332741, 0.328634, 0.346435, 0.3);

  renderTeapot(2.0, 8.0, 0.25, 0.20725, 0.20725,

  1, 0.829, 0.829, 0.296648, 0.296648, 0.296648, 0.088);

  renderTeapot(2.0, 5.0, 0.1745, 0.01175, 0.01175,

  0.61424, 0.04136, 0.04136, 0.727811, 0.626959, 0.626959, 0.6);

  renderTeapot(2.0, 2.0, 0.1, 0.18725, 0.1745,

  0.396, 0.74151, 0.69102, 0.297254, 0.30829, 0.306678, 0.1);

  renderTeapot(6.0, 17.0, 0.329412, 0.223529, 0.027451,

  0.780392, 0.568627, 0.113725, 0.992157, 0.941176, 0.807843,

  0.21794872);

  renderTeapot(6.0, 14.0, 0.2125, 0.1275, 0.054,

  0.714, 0.4284, 0.18144, 0.393548, 0.271906, 0.166721, 0.2);

  renderTeapot(6.0, 11.0, 0.25, 0.25, 0.25,

  0.4, 0.4, 0.4, 0.774597, 0.774597, 0.774597, 0.6);

  renderTeapot(6.0, 8.0, 0.19125, 0.0735, 0.0225,

  0.7038, 0.27048, 0.0828, 0.256777, 0.137622, 0.086014, 0.1);

  renderTeapot(6.0, 5.0, 0.24725, 0.1995, 0.0745,

  0.75164, 0.60648, 0.22648, 0.628281, 0.555802, 0.366065, 0.4);

  renderTeapot(6.0, 2.0, 0.19225, 0.19225, 0.19225,

  0.50754, 0.50754, 0.50754, 0.508273, 0.508273, 0.508273, 0.4);

  renderTeapot(10.0, 17.0, 0.0, 0.0, 0.0, 0.01, 0.01, 0.01,

  0.50, 0.50, 0.50, .25);

  renderTeapot(10.0, 14.0, 0.0, 0.1, 0.06, 0.0, 0.50980392, 0.50980392,

  0.50196078, 0.50196078, 0.50196078, .25);

  renderTeapot(10.0, 11.0, 0.0, 0.0, 0.0,

  0.1, 0.35, 0.1, 0.45, 0.55, 0.45, .25);

  renderTeapot(10.0, 8.0, 0.0, 0.0, 0.0, 0.5, 0.0, 0.0,

  0.7, 0.6, 0.6, .25);

  renderTeapot(10.0, 5.0, 0.0, 0.0, 0.0, 0.55, 0.55, 0.55,

  0.70, 0.70, 0.70, .25);

  renderTeapot(10.0, 2.0, 0.0, 0.0, 0.0, 0.5, 0.5, 0.0,

  0.60, 0.60, 0.50, .25);

  renderTeapot(14.0, 17.0, 0.02, 0.02, 0.02, 0.01, 0.01, 0.01,

  0.4, 0.4, 0.4, .078125);

  renderTeapot(14.0, 14.0, 0.0, 0.05, 0.05, 0.4, 0.5, 0.5,

  0.04, 0.7, 0.7, .078125);

  renderTeapot(14.0, 11.0, 0.0, 0.05, 0.0, 0.4, 0.5, 0.4,

  0.04, 0.7, 0.04, .078125);

  renderTeapot(14.0, 8.0, 0.05, 0.0, 0.0, 0.5, 0.4, 0.4,

  0.7, 0.04, 0.04, .078125);

  renderTeapot(14.0, 5.0, 0.05, 0.05, 0.05, 0.5, 0.5, 0.5,

  0.7, 0.7, 0.7, .078125);

  renderTeapot(14.0, 2.0, 0.05, 0.05, 0.0, 0.5, 0.5, 0.4,

  0.7, 0.7, 0.04, .078125);

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho(0.0, 16.0, 0.0, 16.0*(GLfloat)h/(GLfloat)w,

  -10.0, 10.0);

  else

  glOrtho(0.0, 16.0*(GLfloat)w/(GLfloat)h, 0.0, 16.0,

  -10.0, 10.0);

  glMatrixMode(GL_MODELVIEW);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• /** Main Loop*/

  int main(int argc, char **argv)

  {

  glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize(500, 600);

  glutInitWindowPosition(50,50);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

tess.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /** tess.c* This program demonstrates polygon tessellation.

  * Two tesselated objects are drawn. The first is a

  * rectangle with a triangular hole. The second is a

  * smooth shaded, self-intersecting star.

  *

  * Note the exterior rectangle is drawn with its vertices

  * in counter-clockwise order, but its interior clockwise.

  * Note the combineCallback is needed for the self-intersecting

  * star. Also note that removing the TessProperty for the

  * star will make the interior unshaded (WINDING_ODD).

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• #ifndef CALLBACK#define CALLBACK#endif
• GLuint startList;
• void display (void) {glClear(GL_COLOR_BUFFER_BIT);glColor3f(1.0, 1.0, 1.0);

  glCallList(startList);

  glCallList(startList + 1);

  glFlush();

  }

• void CALLBACK beginCallback(GLenum which){glBegin(which);

  }

• void CALLBACK errorCallback(GLenum errorCode){const GLubyte *estring;
• estring = gluErrorString(errorCode);fprintf(stderr, “Tessellation Error: %s\n”, estring);exit(0);

  }

• void CALLBACK endCallback(void){glEnd();

  }

• void CALLBACK vertexCallback(GLvoid *vertex){const GLdouble *pointer;
• pointer = (GLdouble *) vertex;glColor3dv(pointer+3);glVertex3dv(vertex);

  }

• /* combineCallback is used to create a new vertex when edges* intersect. coordinate location is trivial to calculate,* but weight[4] may be used to average color, normal, or texture

  * coordinate data. In this program, color is weighted.

  */

  void CALLBACK combineCallback(GLdouble coords[3],

  GLdouble *vertex_data[4],

  GLfloat weight[4], GLdouble **dataOut )

  {

  GLdouble *vertex;

  int i;

• vertex = (GLdouble *) malloc(6 * sizeof(GLdouble));
• vertex[0] = coords[0];vertex[1] = coords[1];vertex[2] = coords[2];

  for (i = 3; i < 7; i++)

  vertex[i] = weight[0] * vertex_data[0][i]

  + weight[1] * vertex_data[1][i]

  + weight[2] * vertex_data[2][i]

  + weight[3] * vertex_data[3][i];

  *dataOut = vertex;

  }

• void init (void){GLUtesselator *tobj;

  GLdouble rect[4][3] = {50.0, 50.0, 0.0,

  200.0, 50.0, 0.0,

  200.0, 200.0, 0.0,

  50.0, 200.0, 0.0};

  GLdouble tri[3][3] = {75.0, 75.0, 0.0,

  125.0, 175.0, 0.0,

  175.0, 75.0, 0.0};

  GLdouble star[5][6] = {250.0, 50.0, 0.0, 1.0, 0.0, 1.0,

  325.0, 200.0, 0.0, 1.0, 1.0, 0.0,

  400.0, 50.0, 0.0, 0.0, 1.0, 1.0,

  250.0, 150.0, 0.0, 1.0, 0.0, 0.0,

  400.0, 150.0, 0.0, 0.0, 1.0, 0.0};

• glClearColor(0.0, 0.0, 0.0, 0.0);
• startList = glGenLists(2);
• tobj = gluNewTess();gluTessCallback(tobj, GLU_TESS_VERTEX,glVertex3dv);

  gluTessCallback(tobj, GLU_TESS_BEGIN,

  beginCallback);

  gluTessCallback(tobj, GLU_TESS_END,

  endCallback);

  gluTessCallback(tobj, GLU_TESS_ERROR,

  errorCallback);

• /* rectangle with triangular hole inside */glNewList(startList, GL_COMPILE);glShadeModel(GL_FLAT);

  gluTessBeginPolygon(tobj, NULL);

  gluTessBeginContour(tobj);

  gluTessVertex(tobj, rect[0], rect[0]);

  gluTessVertex(tobj, rect[1], rect[1]);

  gluTessVertex(tobj, rect[2], rect[2]);

  gluTessVertex(tobj, rect[3], rect[3]);

  gluTessEndContour(tobj);

  gluTessBeginContour(tobj);

  gluTessVertex(tobj, tri[0], tri[0]);

  gluTessVertex(tobj, tri[1], tri[1]);

  gluTessVertex(tobj, tri[2], tri[2]);

  gluTessEndContour(tobj);

  gluTessEndPolygon(tobj);

  glEndList();

• gluTessCallback(tobj, GLU_TESS_VERTEX,vertexCallback);gluTessCallback(tobj, GLU_TESS_BEGIN,

  beginCallback);

  gluTessCallback(tobj, GLU_TESS_END,

  endCallback);

  gluTessCallback(tobj, GLU_TESS_ERROR,

  errorCallback);

  gluTessCallback(tobj, GLU_TESS_COMBINE,

  combineCallback);

• /* smooth shaded, self-intersecting star */glNewList(startList + 1, GL_COMPILE);glShadeModel(GL_SMOOTH);

  gluTessProperty(tobj, GLU_TESS_WINDING_RULE,

  GLU_TESS_WINDING_POSITIVE);

  gluTessBeginPolygon(tobj, NULL);

  gluTessBeginContour(tobj);

  gluTessVertex(tobj, star[0], star[0]);

  gluTessVertex(tobj, star[1], star[1]);

  gluTessVertex(tobj, star[2], star[2]);

  gluTessVertex(tobj, star[3], star[3]);

  gluTessVertex(tobj, star[4], star[4]);

  gluTessEndContour(tobj);

  gluTessEndPolygon(tobj);

  glEndList();

  gluDeleteTess(tobj);

  }

• void reshape (int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluOrtho2D(0.0, (GLdouble) w, 0.0, (GLdouble) h);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);

  glutInitWindowSize(500, 500);

  glutCreateWindow(argv[0]);

  init();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

texbind.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* texbind.c* This program demonstrates using glBindTexture() by* creating and managing two textures.

  */

  #include <GL/glut.h>

  #include <stdlib.h>

  #include <stdio.h>

• #ifdef GL_VERSION_1_1/* Create checkerboard texture */#define checkImageWidth 64

  #define checkImageHeight 64

  static GLubyte checkImage[checkImageHeight][checkImageWidth][4];

  static GLubyte otherImage[checkImageHeight][checkImageWidth][4];

• static GLuint texName[2];
• void makeCheckImages(void){int i, j, c;for (i = 0; i < checkImageHeight; i++) {

  for (j = 0; j < checkImageWidth; j++) {

  c = ((((i&0x8)==0)^((j&0x8))==0))*255;

  checkImage[i][j][0] = (GLubyte) c;

  checkImage[i][j][1] = (GLubyte) c;

  checkImage[i][j][2] = (GLubyte) c;

  checkImage[i][j][3] = (GLubyte) 255;

  c = ((((i&0x10)==0)^((j&0x10))==0))*255;

• otherImage[i][j][0] = (GLubyte) c;otherImage[i][j][1] = (GLubyte) 0;otherImage[i][j][2] = (GLubyte) 0;

  otherImage[i][j][3] = (GLubyte) 255;

  }

  }

  }

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glShadeModel(GL_FLAT);

  glEnable(GL_DEPTH_TEST);

• makeCheckImages();glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
• glGenTextures(2, texName);glBindTexture(GL_TEXTURE_2D, texName[0]);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,

  GL_NEAREST);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,

  GL_NEAREST);

  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth,

  checkImageHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,

  checkImage);

• glBindTexture(GL_TEXTURE_2D, texName[1]);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

  glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);

  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth,

  checkImageHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,

• otherImage);glEnable(GL_TEXTURE_2D);}
• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glBindTexture(GL_TEXTURE_2D, texName[0]);

  glBegin(GL_QUADS);

  glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -1.0, 0.0);

  glTexCoord2f(0.0, 1.0); glVertex3f(-2.0, 1.0, 0.0);

  glTexCoord2f(1.0, 1.0); glVertex3f(0.0, 1.0, 0.0);

  glTexCoord2f(1.0, 0.0); glVertex3f(0.0, -1.0, 0.0);

  glEnd();

  glBindTexture(GL_TEXTURE_2D, texName[1]);

  glBegin(GL_QUADS);

  glTexCoord2f(0.0, 0.0); glVertex3f(1.0, -1.0, 0.0);

  glTexCoord2f(0.0, 1.0); glVertex3f(1.0, 1.0, 0.0);

  glTexCoord2f(1.0, 1.0); glVertex3f(2.41421, 1.0, -1.41421);

  glTexCoord2f(1.0, 0.0); glVertex3f(2.41421, -1.0, -1.41421);

  glEnd();

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 30.0);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  glTranslatef(0.0, 0.0, -3.6);

  }

• void keyboard(unsigned char key, int x, int y){switch (key) {

  case 27:

  exit(0);

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize(250, 250);

  glutInitWindowPosition(100, 100);

  glutCreateWindow(argv[0]);

  init();

  glutReshapeFunc(reshape);

  glutDisplayFunc(display);

  glutKeyboardFunc (keyboard);

  glutMainLoop();

  return 0;

  }

  #else

  int main(int argc, char** argv)

  {

  fprintf (stderr, “This program demonstrates a feature which is not in OpenGL Version 1.0.\n”);

  fprintf (stderr, “If your implementation of OpenGL Version 1.0 has the right extensions,\n”);

  fprintf (stderr, “you may be able to modify this program to make it run.\n”);

  return 0;

  }

  #endif

texgen.c

• /** Copyright (c) 1993-1997, Silicon Graphics, Inc.* ALL RIGHTS RESERVED

  * Permission to use, copy, modify, and distribute this software for

  * any purpose and without fee is hereby granted, provided that the above

  * copyright notice appear in all copies and that both the copyright notice

  * and this permission notice appear in supporting documentation, and that

  * the name of Silicon Graphics, Inc. not be used in advertising

  * or publicity pertaining to distribution of the software without specific,

  * written prior permission.

  *

  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU “AS-IS”

  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,

  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR

  * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON

  * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,

  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY

  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,

  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF

  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN

  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON

  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE

  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

  *

  * US Government Users Restricted Rights

  * Use, duplication, or disclosure by the Government is subject to

  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph

  * (c)(1)(ii) of the Rights in Technical Data and Computer Software

  * clause at DFARS 252.227-7013 and/or in similar or successor

  * clauses in the FAR or the DOD or NASA FAR Supplement.

  * Unpublished– rights reserved under the copyright laws of the

  * United States. Contractor/manufacturer is Silicon Graphics,

  * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.

  *

  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

  */

• /* texgen.c* This program draws a texture mapped teapot with* automatically generated texture coordinates. The

  * texture is rendered as stripes on the teapot.

  * Initially, the object is drawn with texture coordinates

  * based upon the object coordinates of the vertex

  * and distance from the plane x = 0. Pressing the ‘e’

  * key changes the coordinate generation to eye coordinates

  * of the vertex. Pressing the ‘o’ key switches it back

  * to the object coordinates. Pressing the ‘s’ key

  * changes the plane to a slanted one (x + y + z = 0).

  * Pressing the ‘x’ key switches it back to x = 0.

  */

• #include <GL/glut.h>#include <stdlib.h>#include <stdio.h>
• #define stripeImageWidth 32GLubyte stripeImage[4*stripeImageWidth];
• #ifdef GL_VERSION_1_1static GLuint texName;#endif
• void makeStripeImage(void){int j;for (j = 0; j < stripeImageWidth; j++) {

  stripeImage[4*j] = (GLubyte) ((j<=4) ? 255 : 0);

  stripeImage[4*j+1] = (GLubyte) ((j>4) ? 255 : 0);

  stripeImage[4*j+2] = (GLubyte) 0;

  stripeImage[4*j+3] = (GLubyte) 255;

  }

  }

• /* planes for texture coordinate generation */static GLfloat xequalzero[] = {1.0, 0.0, 0.0, 0.0};static GLfloat slanted[] = {1.0, 1.0, 1.0, 0.0};

  static GLfloat *currentCoeff;

  static GLenum currentPlane;

  static GLint currentGenMode;

• void init(void){glClearColor (0.0, 0.0, 0.0, 0.0);

  glEnable(GL_DEPTH_TEST);

  glShadeModel(GL_SMOOTH);

• makeStripeImage();glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
• #ifdef GL_VERSION_1_1glGenTextures(1, &texName);glBindTexture(GL_TEXTURE_1D, texName);

  #endif

  glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_REPEAT);

  glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

  glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

  #ifdef GL_VERSION_1_1

  glTexImage1D(GL_TEXTURE_1D, 0, GL_RGBA, stripeImageWidth, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, stripeImage);

  #else

  glTexImage1D(GL_TEXTURE_1D, 0, 4, stripeImageWidth, 0,

  GL_RGBA, GL_UNSIGNED_BYTE, stripeImage);

  #endif

• glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);currentCoeff = xequalzero;currentGenMode = GL_OBJECT_LINEAR;

  currentPlane = GL_OBJECT_PLANE;

  glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, currentGenMode);

  glTexGenfv(GL_S, currentPlane, currentCoeff);

• glEnable(GL_TEXTURE_GEN_S);glEnable(GL_TEXTURE_1D);glEnable(GL_CULL_FACE);

  glEnable(GL_LIGHTING);

  glEnable(GL_LIGHT0);

  glEnable(GL_AUTO_NORMAL);

  glEnable(GL_NORMALIZE);

  glFrontFace(GL_CW);

  glCullFace(GL_BACK);

  glMaterialf (GL_FRONT, GL_SHININESS, 64.0);

  }

• void display(void){glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
• glPushMatrix ();glRotatef(45.0, 0.0, 0.0, 1.0);#ifdef GL_VERSION_1_1

  glBindTexture(GL_TEXTURE_1D, texName);

  #endif

  glutSolidTeapot(2.0);

  glPopMatrix ();

  glFlush();

  }

• void reshape(int w, int h){glViewport(0, 0, (GLsizei) w, (GLsizei) h);

  glMatrixMode(GL_PROJECTION);

  glLoadIdentity();

  if (w <= h)

  glOrtho (-3.5, 3.5, -3.5*(GLfloat)h/(GLfloat)w,

  3.5*(GLfloat)h/(GLfloat)w, -3.5, 3.5);

  else

  glOrtho (-3.5*(GLfloat)w/(GLfloat)h,

  3.5*(GLfloat)w/(GLfloat)h, -3.5, 3.5, -3.5, 3.5);

  glMatrixMode(GL_MODELVIEW);

  glLoadIdentity();

  }

• void keyboard (unsigned char key, int x, int y){switch (key) {

  case ‘e’:

  case ‘E’:

  currentGenMode = GL_EYE_LINEAR;

  currentPlane = GL_EYE_PLANE;

  glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, currentGenMode);

  glTexGenfv(GL_S, currentPlane, currentCoeff);

  glutPostRedisplay();

  break;

  case ‘o’:

  case ‘O’:

  currentGenMode = GL_OBJECT_LINEAR;

  currentPlane = GL_OBJECT_PLANE;

  glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, currentGenMode);

  glTexGenfv(GL_S, currentPlane, currentCoeff);

  glutPostRedisplay();

  break;

  case ‘s’:

  case ‘S’:

  currentCoeff = slanted;

  glTexGenfv(GL_S, currentPlane, currentCoeff);

  glutPostRedisplay();

  break;

  case ‘x’:

  case ‘X’:

  currentCoeff = xequalzero;

  glTexGenfv(GL_S, currentPlane, currentCoeff);

  glutPostRedisplay();

  break;

  case 27:

  exit(0);

  break;

  default:

  break;

  }

  }

• int main(int argc, char** argv){glutInit(&argc, argv);

  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

  glutInitWindowSize(256, 256);

  glutInitWindowPosition(100, 100);

  glutCreateWindow (argv[0]);

  init ();

  glutDisplayFunc(display);

  glutReshapeFunc(reshape);

  glutKeyboardFunc(keyboard);

  glutMainLoop();

  return 0;

  }

PAGE/POST REFERENCES

• Các ví dụ về games với C++ – Example Games
  
• Cơ bản về C++ – Basic C++ Lessons
  
• Examples about Opengl
  
• Functions API useful in the OpenGL/GLUT
  
• Geometric Objects
  
• Giáo trình học C++ bằng video
  
• Help Installing OpenGL to DevC++
  
• OpenGL Tutorials
  

• Writting programs with Opengl – Article: Nguyên lí viết chương trình OpenGL
  
• Basic Facts About C++Builder
  
• Introduction to C++Builder
  
• Tutorial on lighting in OpenGL
  
• OpenGL API-based Code – Detail Listing
  
• OpenGL API Code and Tutorial Listings
  
• [Lập trình] hướng dẫn cài opengl glut, aux vào devc++
  
• Cơ bản về OpenGL