/* Main display routine. Clears the drawing buffer and if transparency is
set, displays the model twice, 1st time accepting those fragments with
a ALPHA value of 1 only, then with DEPTH_BUFFER writing disabled for
those with other values. */
void
display(void)
{
int pass;
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
if (transparent) {
glEnable(GL_ALPHA_TEST);
pass = 2;
} else {
glDisable(GL_ALPHA_TEST);
pass = 0;
}
/* Rotate the whole model */
glRotatef(view_h, 0, 1, 0);
glRotatef(view_v, 1, 0, 0);
do {
if (pass == 2) {
glAlphaFunc(GL_EQUAL, 1);
glDepthMask(GL_TRUE);
pass--;
} else if (pass != 0) {
glAlphaFunc(GL_NOTEQUAL, 1);
glDepthMask(GL_FALSE);
pass--;
}
draw_engine_pole();
glPushMatrix();
glTranslatef(0.5, 1.4, 0.0);
draw_cylinder_head();
glPopMatrix();
glPushMatrix();
glTranslatef(0.0, -0.8, 0.0);
draw_crank();
glPopMatrix();
} while (pass > 0);
glDepthMask(GL_TRUE);
glutSwapBuffers();
glPopMatrix();
}
/* Main display routine. Clears the drawing buffer and if transparency is
set, displays the model twice, 1st time accepting those fragments with
a ALPHA value of 1 only, then with DEPTH_BUFFER writing disabled for
those with other values. */
void
display(void)
{
int pass;
#ifdef STEREO
int i;
/* enclose original rendering code in 2-pass loop */
for (i=0; i<2; i++)
{
/* adjust projection matrix for stereo viewpoint */
if (bStereoEnabled) {
glDrawBuffer((i==0) ? GL_BACK_LEFT : GL_BACK_RIGHT);
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadMatrixf((i==0) ? &mProjectionLeft : &mProjectionRight);
glMatrixMode(GL_MODELVIEW);
}
#endif
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
if (transparent) {
glEnable(GL_ALPHA_TEST);
pass = 2;
} else {
glDisable(GL_ALPHA_TEST);
pass = 0;
}
/* Rotate the whole model */
glRotatef(view_h, 0, 1, 0);
glRotatef(view_v, 1, 0, 0);
do {
if (pass == 2) {
glAlphaFunc(GL_EQUAL, 1);
glDepthMask(GL_TRUE);
pass--;
} else if (pass != 0) {
glAlphaFunc(GL_NOTEQUAL, 1);
glDepthMask(GL_FALSE);
pass--;
}
draw_engine_pole();
glPushMatrix();
glTranslatef(0.5, 1.4, 0.0);
draw_cylinder_head();
glPopMatrix();
glPushMatrix();
glTranslatef(0.0, -0.8, 0.0);
draw_crank();
glPopMatrix();
} while (pass > 0);
glDepthMask(GL_TRUE);
glPopMatrix();
#ifdef STEREO
/* render twice for stereo, or once for mono */
if (bStereoEnabled) {
glFlush();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}
else
break;
} /* for loop */
#endif
glutSwapBuffers();
}
