     src.y *= src.w;
     src.z *= src.w;
 
-    if (frontToBack && (mipMode == 0))
+    if (t_frontToBack && (t_mipMode == 0))
     {
       dst = dst + src * (1.0f - dst.w);
     }
-    else if (!frontToBack && (mipMode == 0))
+    else if (!t_frontToBack && (t_mipMode == 0))
     {
       //dst = dst * src.w + src * (1.0f - src.w);
     }
 
-    if (earlyRayTermination && (dst.w > opacityThreshold))
+    if (t_earlyRayTermination && (dst.w > opacityThreshold))
     {
       break;
     }

  return rgbaFloatToInt(rgba);
}

template<int bpc>
__device__ float3 gradient(const float3& pos)
{
  const float DELTA = 0.01f;

  // Calc hits with clip plane.
  float tpnear;
  float nddot;
  if (t_clipPlane)
  {
    intersectPlane(ray, planeNormal, planeDist, &nddot, &tpnear);
  }
