Hi,

Now I ported my OpenGL application from GLUT to GTK2 with gtkglext. I
changed nearly no OpenGL code, but the result looks very bad:

http://brachttal.net/tmp/depth_test1.jpg

It looks like there's no depth testing activated. But I created the
window with Gdk::GL::MODE_DEPTH and activated it with
glEnable(GL_DEPTH_TEST)..

Do you think it's a depth buffer problem or is also another problem
possible?

I use glScalef() to zoom in and zoom out. Could this be a problem?
Sometimes objects disapear while zooming. Is there a better way to
realize a zoom/camera near/far function? Is a better way to translate
the word into my direction than using glScalef()?

regards
Andreas

Andreas Volz wrote:
> 
> http://brachttal.net/tmp/depth_test1.jpg
> 
> It looks like there's no depth testing activated. But I created the
> window with Gdk::GL::MODE_DEPTH and activated it with
> glEnable(GL_DEPTH_TEST)..
> 

What value does glGet(GL_DEPTH_BITS...) return?


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Am Wed, 03 Aug 2005 11:28:58 +0200 schrieb fungus:

> Andreas Volz wrote:
> > 
> > http://brachttal.net/tmp/depth_test1.jpg
> > 
> > It looks like there's no depth testing activated. But I created the
> > window with Gdk::GL::MODE_DEPTH and activated it with
> > glEnable(GL_DEPTH_TEST)..
> > 
> 
> What value does glGet(GL_DEPTH_BITS...) return?

The problem was really the glScalef() function. Now I changed my resize
Callback to do a gluPerspective() call and a z translate before and now
zoom with glScale() works. (zpr lib did this before, so sorry for this
stupid problem...)

This is my new Rescale function:

  glViewport(0, 0, width, height);

  fAspect = (GLfloat) width / (GLfloat) height;

  camera.reshape (width, height);

  // Reset coordinate system
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();

  // Produce the perspective projection
  gluPerspective(60.0f, fAspect, 1.0, 128.0);

  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glTranslatef(0.0, 0.0, -8.0); // initial camera position

So where is the difference between translating the world "near to me"
and glScale()?

regards
Andreas