better animate rate (Marcelo Magallon)

progs/demos/morph3d.c

@@ -660,6 +660,13 @@ static void draw_ico( void )
 }
 
 static void draw ( void ) {
+  static double t0 = -1.;
+  double dt, t = glutGet(GLUT_ELAPSED_TIME) / 1000.0;
+  if (t0 < 0.0)
+     t0 = t;
+  dt = t - t0;
+  t0 = t;
+
   glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
 
   glPushMatrix();
@@ -681,7 +688,7 @@ static void draw ( void ) {
 
   glutSwapBuffers();
 
-  step+=0.05;
+  step += dt;
 }
 
 static void idle_( void )