*** empty log message ***

1 files changed, 359 insertions, 0 deletions

diff --git a/progs/ggi/gears.c b/progs/ggi/gears.c
new file mode 100644
index 0000000000..a6b5f7dda1
--- /dev/null
+++ b/progs/ggi/gears.c
@@ -0,0 +1,359 @@
+/* $Id: gears.c,v 1.1 1999/08/21 06:27:37 jtaylor Exp $ */
+
+/*
+ * 3-D gear wheels.  This program is in the public domain.
+ *
+ * Brian Paul
+ */
+
+/* Conversion to GLUT by Mark J. Kilgard */
+
+/*
+ * $Log: gears.c,v $
+ * Revision 1.1  1999/08/21 06:27:37  jtaylor
+ * *** empty log message ***
+ *
+ * Revision 1.5  1999/07/31 21:51:09  jtaylor
+ * *** empty log message ***
+ *
+ * Revision 3.2  1999/06/03 17:07:36  brianp
+ * an extra quad was being drawn in front and back faces
+ *
+ * Revision 3.1  1998/11/03 02:49:10  brianp
+ * added fps output
+ *
+ * Revision 3.0  1998/02/14 18:42:29  brianp
+ * initial rev
+ *
+ */
+
+
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <GL/glut.h>
+
+#ifndef M_PI
+#define M_PI 3.14159265
+#endif
+
+static GLint T0 = 0;
+static GLint Frames = 0;
+
+
+/**
+
+  Draw a gear wheel.  You'll probably want to call this function when
+  building a display list since we do a lot of trig here.
+ 
+  Input:  inner_radius - radius of hole at center
+          outer_radius - radius at center of teeth
+          width - width of gear
+          teeth - number of teeth
+          tooth_depth - depth of tooth
+
+ **/
+
+static void
+gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
+  GLint teeth, GLfloat tooth_depth)
+{
+  GLint i;
+  GLfloat r0, r1, r2;
+  GLfloat angle, da;
+  GLfloat u, v, len;
+
+  r0 = inner_radius;
+  r1 = outer_radius - tooth_depth / 2.0;
+  r2 = outer_radius + tooth_depth / 2.0;
+
+  da = 2.0 * M_PI / teeth / 4.0;
+
+  glShadeModel(GL_FLAT);
+
+  glNormal3f(0.0, 0.0, 1.0);
+
+  /* draw front face */
+  glBegin(GL_QUAD_STRIP);
+  for (i = 0; i <= teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+    glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
+    if (i < teeth) {
+      glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
+      glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
+    }
+  }
+  glEnd();
+
+  /* draw front sides of teeth */
+  glBegin(GL_QUADS);
+  da = 2.0 * M_PI / teeth / 4.0;
+  for (i = 0; i < teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
+    glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
+    glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5);
+    glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
+  }
+  glEnd();
+
+  glNormal3f(0.0, 0.0, -1.0);
+
+  /* draw back face */
+  glBegin(GL_QUAD_STRIP);
+  for (i = 0; i <= teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
+    glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
+    if (i < teeth) {
+      glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
+      glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
+    }
+  }
+  glEnd();
+
+  /* draw back sides of teeth */
+  glBegin(GL_QUADS);
+  da = 2.0 * M_PI / teeth / 4.0;
+  for (i = 0; i < teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+
+    glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
+    glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5);
+    glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
+  }
+  glEnd();
+
+  /* draw outward faces of teeth */
+  glBegin(GL_QUAD_STRIP);
+  for (i = 0; i < teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
+    glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
+    u = r2 * cos(angle + da) - r1 * cos(angle);
+    v = r2 * sin(angle + da) - r1 * sin(angle);
+    len = sqrt(u * u + v * v);
+    u /= len;
+    v /= len;
+    glNormal3f(v, -u, 0.0);
+    glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
+    glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
+    glNormal3f(cos(angle), sin(angle), 0.0);
+    glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5);
+    glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5);
+    u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
+    v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
+    glNormal3f(v, -u, 0.0);
+    glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
+    glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
+    glNormal3f(cos(angle), sin(angle), 0.0);
+  }
+
+  glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
+  glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);
+
+  glEnd();
+
+  glShadeModel(GL_SMOOTH);
+
+  /* draw inside radius cylinder */
+  glBegin(GL_QUAD_STRIP);
+  for (i = 0; i <= teeth; i++) {
+    angle = i * 2.0 * M_PI / teeth;
+    glNormal3f(-cos(angle), -sin(angle), 0.0);
+    glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
+    glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
+  }
+  glEnd();
+
+}
+
+static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
+static GLint gear1, gear2, gear3;
+static GLfloat angle = 0.0;
+
+static void
+draw(void)
+{
+  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+  glPushMatrix();
+  glRotatef(view_rotx, 1.0, 0.0, 0.0);
+  glRotatef(view_roty, 0.0, 1.0, 0.0);
+  glRotatef(view_rotz, 0.0, 0.0, 1.0);
+
+  glPushMatrix();
+  glTranslatef(-3.0, -2.0, 0.0);
+  glRotatef(angle, 0.0, 0.0, 1.0);
+  glCallList(gear1);
+  glPopMatrix();
+
+  glPushMatrix();
+  glTranslatef(3.1, -2.0, 0.0);
+  glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
+  glCallList(gear2);
+  glPopMatrix();
+
+  glPushMatrix();
+  glTranslatef(-3.1, 4.2, 0.0);
+  glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
+  glCallList(gear3);
+  glPopMatrix();
+
+  glPopMatrix();
+
+  glutSwapBuffers();
+
+  Frames++;
+  {
+     GLint t = glutGet(GLUT_ELAPSED_TIME);
+     if (t - T0 >= 5000) {
+        GLfloat seconds = (t - T0) / 1000.0;
+        GLfloat fps = Frames / seconds;
+        printf("%d frames in %g seconds = %g FPS\n", Frames, seconds, fps);
+        T0 = t;
+        Frames = 0;
+     }
+  }
+}
+
+
+static void
+idle(void)
+{
+  angle += 2.0;
+  glutPostRedisplay();
+}
+
+/* change view angle, exit upon ESC */
+/* ARGSUSED1 */
+static void
+key(unsigned char k, int x, int y)
+{
+  switch (k) {
+  case 'z':
+    view_rotz += 5.0;
+    break;
+  case 'Z':
+    view_rotz -= 5.0;
+    break;
+  case 27:  /* Escape */
+    exit(0);
+    break;
+  default:
+    return;
+  }
+  glutPostRedisplay();
+}
+
+/* change view angle */
+/* ARGSUSED1 */
+static void
+special(int k, int x, int y)
+{
+  switch (k) {
+  case GLUT_KEY_UP:
+    view_rotx += 5.0;
+    break;
+  case GLUT_KEY_DOWN:
+    view_rotx -= 5.0;
+    break;
+  case GLUT_KEY_LEFT:
+    view_roty += 5.0;
+    break;
+  case GLUT_KEY_RIGHT:
+    view_roty -= 5.0;
+    break;
+  default:
+    return;
+  }
+  glutPostRedisplay();
+}
+
+/* new window size or exposure */
+static void
+reshape(int width, int height)
+{
+  GLfloat h = (GLfloat) height / (GLfloat) width;
+
+  glViewport(0, 0, (GLint) width, (GLint) height);
+  glMatrixMode(GL_PROJECTION);
+  glLoadIdentity();
+  glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);
+  glMatrixMode(GL_MODELVIEW);
+  glLoadIdentity();
+  glTranslatef(0.0, 0.0, -40.0);
+}
+
+static void
+init(void)
+{
+  static GLfloat pos[4] =
+  {5.0, 5.0, 10.0, 0.0};
+  static GLfloat red[4] =
+  {0.8, 0.1, 0.0, 1.0};
+  static GLfloat green[4] =
+  {0.0, 0.8, 0.2, 1.0};
+  static GLfloat blue[4] =
+  {0.2, 0.2, 1.0, 1.0};
+
+  glLightfv(GL_LIGHT0, GL_POSITION, pos);
+  glEnable(GL_CULL_FACE);
+  glEnable(GL_LIGHTING);
+  glEnable(GL_LIGHT0);
+  glEnable(GL_DEPTH_TEST);
+
+  /* make the gears */
+  gear1 = glGenLists(1);
+  glNewList(gear1, GL_COMPILE);
+  glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red);
+  gear(1.0, 4.0, 1.0, 20, 0.7);
+  glEndList();
+
+  gear2 = glGenLists(1);
+  glNewList(gear2, GL_COMPILE);
+  glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
+  gear(0.5, 2.0, 2.0, 10, 0.7);
+  glEndList();
+
+  gear3 = glGenLists(1);
+  glNewList(gear3, GL_COMPILE);
+  glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
+  gear(1.3, 2.0, 0.5, 10, 0.7);
+  glEndList();
+
+  glEnable(GL_NORMALIZE);
+}
+
+void 
+visible(int vis)
+{
+  if (vis == GLUT_VISIBLE)
+    glutIdleFunc(idle);
+  else
+    glutIdleFunc(NULL);
+}
+
+int main(int argc, char *argv[])
+{
+  glutInit(&argc, argv);
+  glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
+
+  glutInitWindowPosition(0, 0);
+  glutInitWindowSize(300, 300);
+  glutCreateWindow("Gears");
+  init();
+
+  glutDisplayFunc(draw);
+  glutReshapeFunc(reshape);
+  glutKeyboardFunc(key);
+  glutSpecialFunc(special);
+  glutVisibilityFunc(visible);
+
+  glutMainLoop();
+  return 0;             /* ANSI C requires main to return int. */
+}