progs/util/glutskel.c

   1 /**
   2  * A skeleton/template GLUT program
   3  *
   4  * Written by Brian Paul and in the public domain.
   5  */
   6
   7
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <math.h>
  11 #include <GL/glut.h>
  12
  13 static int Win;
  14 static int WinWidth = 400, WinHeight = 400;
  15 static GLfloat Xrot = 0, Yrot = 0, Zrot = 0;
  16 static GLboolean Anim = GL_FALSE;
  17
  18
  19 static void
  20 Idle(void)
  21 {
  22    Xrot += 3.0;
  23    Yrot += 4.0;
  24    Zrot += 2.0;
  25    glutPostRedisplay();
  26 }
  27
  28
  29 static void
  30 Draw(void)
  31 {
  32    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  33
  34    glPushMatrix();
  35    glRotatef(Xrot, 1, 0, 0);
  36    glRotatef(Yrot, 0, 1, 0);
  37    glRotatef(Zrot, 0, 0, 1);
  38
  39    glutSolidCube(2.0);
  40
  41    glPopMatrix();
  42
  43    glutSwapBuffers();
  44 }
  45
  46
  47 static void
  48 Reshape(int width, int height)
  49 {
  50    WinWidth = width;
  51    WinHeight = height;
  52    glViewport(0, 0, width, height);
  53    glMatrixMode(GL_PROJECTION);
  54    glLoadIdentity();
  55    glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
  56    glMatrixMode(GL_MODELVIEW);
  57    glLoadIdentity();
  58    glTranslatef(0.0, 0.0, -15.0);
  59 }
  60
  61
  62 static void
  63 Key(unsigned char key, int x, int y)
  64 {
  65    const GLfloat step = 3.0;
  66    (void) x;
  67    (void) y;
  68    switch (key) {
  69    case 'a':
  70       Anim = !Anim;
  71       if (Anim)
  72          glutIdleFunc(Idle);
  73       else
  74          glutIdleFunc(NULL);
  75       break;
  76    case 'z':
  77       Zrot -= step;
  78       break;
  79    case 'Z':
  80       Zrot += step;
  81       break;
  82    case 27:
  83       glutDestroyWindow(Win);
  84       exit(0);
  85       break;
  86    }
  87    glutPostRedisplay();
  88 }
  89
  90
  91 static void
  92 SpecialKey(int key, int x, int y)
  93 {
  94    const GLfloat step = 3.0;
  95    (void) x;
  96    (void) y;
  97    switch (key) {
  98    case GLUT_KEY_UP:
  99       Xrot -= step;
 100       break;
 101    case GLUT_KEY_DOWN:
 102       Xrot += step;
 103       break;
 104    case GLUT_KEY_LEFT:
 105       Yrot -= step;
 106       break;
 107    case GLUT_KEY_RIGHT:
 108       Yrot += step;
 109       break;
 110    }
 111    glutPostRedisplay();
 112 }
 113
 114
 115 static void
 116 Init(void)
 117 {
 118    /* setup lighting, etc */
 119    glEnable(GL_DEPTH_TEST);
 120    glEnable(GL_LIGHTING);
 121    glEnable(GL_LIGHT0);
 122 }
 123
 124
 125 int
 126 main(int argc, char *argv[])
 127 {
 128    glutInit(&argc, argv);
 129    glutInitWindowSize(WinWidth, WinHeight);
 130    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
 131    Win = glutCreateWindow(argv[0]);
 132    glutReshapeFunc(Reshape);
 133    glutKeyboardFunc(Key);
 134    glutSpecialFunc(SpecialKey);
 135    glutDisplayFunc(Draw);
 136    if (Anim)
 137       glutIdleFunc(Idle);
 138    Init();
 139    glutMainLoop();
 140    return 0;
 141 }