title: Disable culling of images in openGL
body: <p>I am creating a circlular sphere with two layers:<br/>
  one having the light layer above (radius 300)<br/>
  one having the darker color layer (radius 298)<br/></p>
  
  <p>When I draw this sphere on my window, I get the sphere drawn properly. </p>
  
  <p>The following code is not exactly <code>openGL</code> but the <code>openGL</code> folks won't have any problem understanding it</p>
  
  <p>ofImage sphericalImage;
  GLUquadricObj *quadric;</p>
  
  <p>ofPushMatrix();</p>
  
  <pre><code>    //Sphere dark image
      ofRotateX(90);
      ofPushStyle();
      ofSetColor(43,64,105);
      sphericalImage.getTextureReference().bind();
      gluSphere(quadric, 298, 100, 100);
      ofPopStyle();
  
      //Sphere light image
      ofPushStyle();
      ofSetColor(255,255,255);
      sphericalImage.getTextureReference().bind();
      gluSphere(quadric, 300, 100, 100);
      ofPopStyle();
      sphericalImage.unbind();
  </code></pre>
  
  <p>ofPopMatrix();</p>
  
  <p>However, the problem is at some portions, the front image (lighter one) actually overidies/covers the back spherical image (and the darker portion is not fully visible). When the sphere is rotated with the camera, sometimes the region becomes visible depending on the rotation angles/axis. I want to disable this so that the kind of effect does not take place.</p>
  
  <p>I was earlier thinking if this is related to face-cullin in openGL but I disbaled by setting <code>glDisable(GL_CULL_FACE)</code> and it didn't have any effect. <code>glEnable(GL_DEPTH_TEST);</code> is also set. Any suggestions on how I could disable this so that both the spherical images are visible?</p>