progs/redbook/varray.c

   1 /*
   2  * Copyright (c) 1993-1997, Silicon Graphics, Inc.
   3  * ALL RIGHTS RESERVED
   4  * Permission to use, copy, modify, and distribute this software for
   5  * any purpose and without fee is hereby granted, provided that the above
   6  * copyright notice appear in all copies and that both the copyright notice
   7  * and this permission notice appear in supporting documentation, and that
   8  * the name of Silicon Graphics, Inc. not be used in advertising
   9  * or publicity pertaining to distribution of the software without specific,
  10  * written prior permission.
  11  *
  12  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
  13  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
  14  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
  15  * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
  16  * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
  17  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
  18  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
  19  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
  20  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
  21  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
  22  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
  23  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
  24  *
  25  * US Government Users Restricted Rights
  26  * Use, duplication, or disclosure by the Government is subject to
  27  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
  28  * (c)(1)(ii) of the Rights in Technical Data and Computer Software
  29  * clause at DFARS 252.227-7013 and/or in similar or successor
  30  * clauses in the FAR or the DOD or NASA FAR Supplement.
  31  * Unpublished-- rights reserved under the copyright laws of the
  32  * United States.  Contractor/manufacturer is Silicon Graphics,
  33  * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
  34  *
  35  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.
  36  */
  37
  38 /*
  39  *  varray.c
  40  *  This program demonstrates vertex arrays.
  41  */
  42 #include <GL/glut.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45
  46 #ifdef GL_VERSION_1_1
  47 #define POINTER 1
  48 #define INTERLEAVED 2
  49
  50 #define DRAWARRAY 1
  51 #define ARRAYELEMENT  2
  52 #define DRAWELEMENTS 3
  53
  54 int setupMethod = POINTER;
  55 int derefMethod = DRAWARRAY;
  56
  57 static void setupPointers(void)
  58 {
  59    static GLint vertices[] = {25, 25,
  60                        100, 325,
  61                        175, 25,
  62                        175, 325,
  63                        250, 25,
  64                        325, 325};
  65    static GLfloat colors[] = {1.0, 0.2, 0.2,
  66                        0.2, 0.2, 1.0,
  67                        0.8, 1.0, 0.2,
  68                        0.75, 0.75, 0.75,
  69                        0.35, 0.35, 0.35,
  70                        0.5, 0.5, 0.5};
  71
  72    glEnableClientState (GL_VERTEX_ARRAY);
  73    glEnableClientState (GL_COLOR_ARRAY);
  74
  75    glVertexPointer (2, GL_INT, 0, vertices);
  76    glColorPointer (3, GL_FLOAT, 0, colors);
  77 }
  78
  79 static void setupInterleave(void)
  80 {
  81    static GLfloat intertwined[] =
  82       {1.0, 0.2, 1.0, 100.0, 100.0, 0.0,
  83        1.0, 0.2, 0.2, 0.0, 200.0, 0.0,
  84        1.0, 1.0, 0.2, 100.0, 300.0, 0.0,
  85        0.2, 1.0, 0.2, 200.0, 300.0, 0.0,
  86        0.2, 1.0, 1.0, 300.0, 200.0, 0.0,
  87        0.2, 0.2, 1.0, 200.0, 100.0, 0.0};
  88
  89    glInterleavedArrays (GL_C3F_V3F, 0, intertwined);
  90 }
  91
  92 static void init(void)
  93 {
  94    glClearColor (0.0, 0.0, 0.0, 0.0);
  95    glShadeModel (GL_SMOOTH);
  96    setupPointers ();
  97 }
  98
  99 static void display(void)
 100 {
 101    glClear (GL_COLOR_BUFFER_BIT);
 102
 103    if (derefMethod == DRAWARRAY)
 104       glDrawArrays (GL_TRIANGLES, 0, 6);
 105    else if (derefMethod == ARRAYELEMENT) {
 106       glBegin (GL_TRIANGLES);
 107       glArrayElement (2);
 108       glArrayElement (3);
 109       glArrayElement (5);
 110       glEnd ();
 111    }
 112    else if (derefMethod == DRAWELEMENTS) {
 113       GLuint indices[4] = {0, 1, 3, 4};
 114
 115       glDrawElements (GL_POLYGON, 4, GL_UNSIGNED_INT, indices);
 116    }
 117    glFlush ();
 118 }
 119
 120 static void reshape (int w, int h)
 121 {
 122    glViewport (0, 0, (GLsizei) w, (GLsizei) h);
 123    glMatrixMode (GL_PROJECTION);
 124    glLoadIdentity ();
 125    gluOrtho2D (0.0, (GLdouble) w, 0.0, (GLdouble) h);
 126 }
 127
 128 /* ARGSUSED2 */
 129 static void mouse (int button, int state, int x, int y)
 130 {
 131    switch (button) {
 132       case GLUT_LEFT_BUTTON:
 133          if (state == GLUT_DOWN) {
 134             if (setupMethod == POINTER) {
 135                setupMethod = INTERLEAVED;
 136                setupInterleave();
 137             }
 138             else if (setupMethod == INTERLEAVED) {
 139                setupMethod = POINTER;
 140                setupPointers();
 141             }
 142             glutPostRedisplay();
 143          }
 144          break;
 145       case GLUT_MIDDLE_BUTTON:
 146       case GLUT_RIGHT_BUTTON:
 147          if (state == GLUT_DOWN) {
 148             if (derefMethod == DRAWARRAY)
 149                derefMethod = ARRAYELEMENT;
 150             else if (derefMethod == ARRAYELEMENT)
 151                derefMethod = DRAWELEMENTS;
 152             else if (derefMethod == DRAWELEMENTS)
 153                derefMethod = DRAWARRAY;
 154             glutPostRedisplay();
 155          }
 156          break;
 157       default:
 158          break;
 159    }
 160 }
 161
 162 /* ARGSUSED1 */
 163 static void keyboard(unsigned char key, int x, int y)
 164 {
 165    switch (key) {
 166       case 27:
 167          exit(0);
 168          break;
 169    }
 170 }
 171
 172 int main(int argc, char** argv)
 173 {
 174    glutInit(&argc, argv);
 175    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
 176    glutInitWindowSize (350, 350);
 177    glutInitWindowPosition (100, 100);
 178    glutCreateWindow (argv[0]);
 179    init ();
 180    glutDisplayFunc(display);
 181    glutReshapeFunc(reshape);
 182    glutMouseFunc(mouse);
 183    glutKeyboardFunc (keyboard);
 184    glutMainLoop();
 185    return 0;
 186 }
 187 #else
 188 int main(int argc, char** argv)
 189 {
 190     fprintf (stderr, "This program demonstrates a feature which is not in OpenGL Version 1.0.\n");
 191     fprintf (stderr, "If your implementation of OpenGL Version 1.0 has the right extensions,\n");
 192     fprintf (stderr, "you may be able to modify this program to make it run.\n");
 193     return 0;
 194 }
 195 #endif