         fragmentColor =
             fragmentColor + sampleColor * (1.0f - fragmentColor.w);
 
-        if (fragmentColor.w > 0.1 && position.w == -2)
+        if (fragmentColor.w > alphaThresholdForDepth && position.w == -2)
         {
           setPositionAndDepth(vec4(startPos_eye, 1));
         }

uniform mat4 inverseViewMatrix;
uniform vec3 textureAtlasSize;
uniform vec3 sampleDistance;

uniform sampler3D volumeSampler;


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

    if (objectId == 0 && fragmentColor.w > alphaThresholdForDepth &&
        position.w == -2)
    {
      setPositionAndDepth(currentFragment.eyePos);
    }
