Initial revision
diff --git a/progs/demos/bounce.c b/progs/demos/bounce.c
new file mode 100644
index 0000000..876ce58
--- /dev/null
+++ b/progs/demos/bounce.c
@@ -0,0 +1,240 @@
+/* $Id: bounce.c,v 1.1 1999/08/19 00:55:40 jtg Exp $ */
+
+/*
+ * Bouncing ball demo. Color index mode only!
+ *
+ * This program is in the public domain
+ *
+ * Brian Paul
+ */
+
+/* Conversion to GLUT by Mark J. Kilgard */
+
+/*
+ * $Log: bounce.c,v $
+ * Revision 1.1 1999/08/19 00:55:40 jtg
+ * Initial revision
+ *
+ * Revision 3.3 1999/03/18 08:16:14 joukj
+ *
+ * cmpstr needs string.h to included to avoid warnings
+ *
+ * Revision 3.2 1998/11/28 01:13:02 brianp
+ * now sets an initial window position and size
+ *
+ * Revision 3.1 1998/11/28 01:06:57 brianp
+ * now works in RGB mode by default
+ *
+ * Revision 3.0 1998/02/14 18:42:29 brianp
+ * initial rev
+ *
+ */
+
+
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+#include <GL/glut.h>
+
+#define COS(X) cos( (X) * 3.14159/180.0 )
+#define SIN(X) sin( (X) * 3.14159/180.0 )
+
+#define RED 1
+#define WHITE 2
+#define CYAN 3
+
+GLboolean IndexMode = GL_FALSE;
+GLuint Ball;
+GLenum Mode;
+GLfloat Zrot = 0.0, Zstep = 6.0;
+GLfloat Xpos = 0.0, Ypos = 1.0;
+GLfloat Xvel = 0.2, Yvel = 0.0;
+GLfloat Xmin = -4.0, Xmax = 4.0;
+GLfloat Ymin = -3.8, Ymax = 4.0;
+GLfloat G = -0.1;
+
+static GLuint
+make_ball(void)
+{
+ GLuint list;
+ GLfloat a, b;
+ GLfloat da = 18.0, db = 18.0;
+ GLfloat radius = 1.0;
+ GLuint color;
+ GLfloat x, y, z;
+
+ list = glGenLists(1);
+
+ glNewList(list, GL_COMPILE);
+
+ color = 0;
+ for (a = -90.0; a + da <= 90.0; a += da) {
+
+ glBegin(GL_QUAD_STRIP);
+ for (b = 0.0; b <= 360.0; b += db) {
+
+ if (color) {
+ glIndexi(RED);
+ glColor3f(1, 0, 0);
+ } else {
+ glIndexi(WHITE);
+ glColor3f(1, 1, 1);
+ }
+
+ x = COS(b) * COS(a);
+ y = SIN(b) * COS(a);
+ z = SIN(a);
+ glVertex3f(x, y, z);
+
+ x = radius * COS(b) * COS(a + da);
+ y = radius * SIN(b) * COS(a + da);
+ z = radius * SIN(a + da);
+ glVertex3f(x, y, z);
+
+ color = 1 - color;
+ }
+ glEnd();
+
+ }
+
+ glEndList();
+
+ return list;
+}
+
+static void
+reshape(int width, int height)
+{
+ float aspect = (float) width / (float) height;
+ glViewport(0, 0, (GLint) width, (GLint) height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(-6.0 * aspect, 6.0 * aspect, -6.0, 6.0, -6.0, 6.0);
+ glMatrixMode(GL_MODELVIEW);
+}
+
+/* ARGSUSED1 */
+static void
+key(unsigned char k, int x, int y)
+{
+ switch (k) {
+ case 27: /* Escape */
+ exit(0);
+ }
+}
+
+static void
+draw(void)
+{
+ GLint i;
+
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ glIndexi(CYAN);
+ glColor3f(0, 1, 1);
+ glBegin(GL_LINES);
+ for (i = -5; i <= 5; i++) {
+ glVertex2i(i, -5);
+ glVertex2i(i, 5);
+ }
+ for (i = -5; i <= 5; i++) {
+ glVertex2i(-5, i);
+ glVertex2i(5, i);
+ }
+ for (i = -5; i <= 5; i++) {
+ glVertex2i(i, -5);
+ glVertex2f(i * 1.15, -5.9);
+ }
+ glVertex2f(-5.3, -5.35);
+ glVertex2f(5.3, -5.35);
+ glVertex2f(-5.75, -5.9);
+ glVertex2f(5.75, -5.9);
+ glEnd();
+
+ glPushMatrix();
+ glTranslatef(Xpos, Ypos, 0.0);
+ glScalef(2.0, 2.0, 2.0);
+ glRotatef(8.0, 0.0, 0.0, 1.0);
+ glRotatef(90.0, 1.0, 0.0, 0.0);
+ glRotatef(Zrot, 0.0, 0.0, 1.0);
+
+ glCallList(Ball);
+
+ glPopMatrix();
+
+ glFlush();
+ glutSwapBuffers();
+}
+
+static void
+idle(void)
+{
+ static float vel0 = -100.0;
+
+ Zrot += Zstep;
+
+ Xpos += Xvel;
+ if (Xpos >= Xmax) {
+ Xpos = Xmax;
+ Xvel = -Xvel;
+ Zstep = -Zstep;
+ }
+ if (Xpos <= Xmin) {
+ Xpos = Xmin;
+ Xvel = -Xvel;
+ Zstep = -Zstep;
+ }
+ Ypos += Yvel;
+ Yvel += G;
+ if (Ypos < Ymin) {
+ Ypos = Ymin;
+ if (vel0 == -100.0)
+ vel0 = fabs(Yvel);
+ Yvel = vel0;
+ }
+ glutPostRedisplay();
+}
+
+void
+visible(int vis)
+{
+ if (vis == GLUT_VISIBLE)
+ glutIdleFunc(idle);
+ else
+ glutIdleFunc(NULL);
+}
+
+int main(int argc, char *argv[])
+{
+ glutInit(&argc, argv);
+ glutInitWindowPosition(0, 0);
+ glutInitWindowSize(600, 450);
+
+
+ IndexMode = argc > 1 && strcmp(argv[1], "-ci") == 0;
+ if (IndexMode)
+ glutInitDisplayMode(GLUT_INDEX | GLUT_DOUBLE);
+ else
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+
+ glutCreateWindow("Bounce");
+ Ball = make_ball();
+ glCullFace(GL_BACK);
+ glEnable(GL_CULL_FACE);
+ glDisable(GL_DITHER);
+ glShadeModel(GL_FLAT);
+
+ glutDisplayFunc(draw);
+ glutReshapeFunc(reshape);
+ glutVisibilityFunc(visible);
+ glutKeyboardFunc(key);
+
+ if (IndexMode) {
+ glutSetColor(RED, 1.0, 0.0, 0.0);
+ glutSetColor(WHITE, 1.0, 1.0, 1.0);
+ glutSetColor(CYAN, 0.0, 1.0, 1.0);
+ }
+
+ glutMainLoop();
+ return 0; /* ANSI C requires main to return int. */
+}