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