   uvec2 ij = uvec2(pos.xy);
   uint32_t pix = (ij.x + ij.y * u_ScreenSz);
 
-  gl_FragDepth = 0.0;
+  gl_FragDepth = 1.0;
+  position = vec4(-2, -2, 1, -2);
 
   uint maxAge = u_Counts[Saddr(ij)];
 

    objectId = currentFragment.objectId;
    updateActiveObjects(objectId, activeObjects);
    activeObjectCount = bitCount(activeObjects);

    // fetch next Fragment
    nextFragmentReadStatus = false;

      ++age;
  }

  for (--age; age < maxAge; age++)  // all fragments
  {
    currentFragment = nextFragment;
