Initial revision
diff --git a/progs/xdemos/vgears.c b/progs/xdemos/vgears.c
new file mode 100644
index 0000000..13d030a
--- /dev/null
+++ b/progs/xdemos/vgears.c
@@ -0,0 +1,282 @@
+/* $ID$ */
+
+/*
+ * Spinning gears demo for Linux SVGA/Mesa interface in 32K color mode.
+ *
+ * Compile with: gcc vgears.c -I../include -L../lib -lMesaGL -lX11 -lXext
+ * -lvga -lm -o vgears
+ *
+ * This program is in the public domain.
+ * Brian Paul, January 1996
+ */
+
+
+#include <vga.h>
+#include <math.h>
+#include "GL/svgamesa.h"
+#include "GL/gl.h"
+
+
+int width = 800, height = 600;
+
+SVGAMesaContext vmc;
+
+
+
+/*
+ * 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 );
+ 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 );
+ 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 GLuint limit;
+static GLuint count = 1;
+
+
+static void draw( void )
+{
+ angle += 2.0;
+
+ 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();
+
+ SVGAMesaSwapBuffers();
+}
+
+
+static void init( void )
+{
+ static GLfloat pos[4] = {5.0, 5.0, 10.0, 1.0 };
+ 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 };
+
+ GLfloat w = (float) width / (float) height;
+ GLfloat h = 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 );
+
+
+ glViewport( 0, 0, width, height );
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ if (width>height) {
+ GLfloat w = (GLfloat) width / (GLfloat) height;
+ glFrustum( -w, w, -1.0, 1.0, 5.0, 60.0 );
+ }
+ else {
+ GLfloat h = (GLfloat) height / (GLfloat) width;
+ glFrustum( -1.0, 1.0, -h, h, 5.0, 60.0 );
+ }
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef( 0.0, 0.0, -40.0 );
+}
+
+void setup( void )
+{
+ vga_init();
+
+ vga_setmode(G800x600x32K);
+/* gl_setcontextvga(G800x600x32K);*/
+
+ vmc = SVGAMesaCreateContext(GL_TRUE);
+ SVGAMesaMakeCurrent( vmc );
+}
+
+
+void end( void )
+{
+ SVGAMesaDestroyContext( vmc );
+
+ vga_setmode( TEXT );
+}
+
+
+int main( int argc, char *argv[] )
+{
+ int i;
+
+ setup();
+ init();
+ for (i=0;i<4;i++) {
+ draw(); /*SVGAMesaSwapBuffers();*/
+ }
+ end();
+ return 0;
+}