diff --git a/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.h b/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.h
index c1310c4c..156601ee 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.h
+++ b/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.h
@@ -31,6 +31,10 @@ freely, subject to the following restrictions:
 #include "PolyVoxCore/Region.h"
 #include "PolyVoxCore/Raycast.h"
 
+//These two should not be here!
+#include "PolyVoxCore/Material.h"
+#include "PolyVoxCore/SimpleVolume.h"
+
 #include <algorithm>
 
 namespace PolyVox
@@ -39,12 +43,16 @@ namespace PolyVox
 	class AmbientOcclusionCalculator
 	{
 	public:
-		AmbientOcclusionCalculator(VolumeType<VoxelType>* volInput, Array<3, uint8_t>* arrayResult, Region region, float fRayLength, uint8_t uNoOfSamplesPerOutputElement);
+		AmbientOcclusionCalculator(VolumeType<VoxelType>* volInput, Array<3, uint8_t>* arrayResult, Region region, float fRayLength, uint8_t uNoOfSamplesPerOutputElement/*, polyvox_function<bool(const VoxelType& voxel)> funcIsTransparent*/);
 		~AmbientOcclusionCalculator();
 
 		void execute(void);
 
 	private:
+
+		//bool raycastCallback(const typename VolumeType<VoxelType>::Sampler& sampler);
+		bool raycastCallback(const typename SimpleVolume<VoxelType>::Sampler& sampler);
+
 		Region m_region;
 		typename VolumeType<VoxelType>::Sampler m_sampVolume;
 		VolumeType<VoxelType>* m_volInput;
@@ -56,6 +64,8 @@ namespace PolyVox
 		uint16_t mRandomUnitVectorIndex;
 		uint16_t mRandomVectorIndex;
 		uint16_t mIndexIncreament;
+
+		polyvox_function<bool(const VoxelType& voxel)> m_funcIsTransparent;
 	};
 }
 
diff --git a/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.inl b/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.inl
index 301ee0f2..e80b3911 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/AmbientOcclusionCalculator.inl
@@ -24,7 +24,7 @@ freely, subject to the following restrictions:
 namespace PolyVox
 {
 	template< template<typename> class VolumeType, typename VoxelType>
-	AmbientOcclusionCalculator<VolumeType, VoxelType>::AmbientOcclusionCalculator(VolumeType<VoxelType>* volInput, Array<3, uint8_t>* arrayResult, Region region, float fRayLength, uint8_t uNoOfSamplesPerOutputElement)
+	AmbientOcclusionCalculator<VolumeType, VoxelType>::AmbientOcclusionCalculator(VolumeType<VoxelType>* volInput, Array<3, uint8_t>* arrayResult, Region region, float fRayLength, uint8_t uNoOfSamplesPerOutputElement/*, polyvox_function<bool(const VoxelType& voxel)> funcIsTransparent*/)
 		:m_region(region)
 		,m_sampVolume(volInput)
 		,m_volInput(volInput)
@@ -33,6 +33,7 @@ namespace PolyVox
 		,m_uNoOfSamplesPerOutputElement(uNoOfSamplesPerOutputElement)
 		,mRandomUnitVectorIndex(0) //Although these could be uninitialised, we 
 		,mRandomVectorIndex(0) //initialise for consistant results in the tests.
+		//,m_funcIsTransparent(funcIsTransparent)
 	{
 		//Make sure that the size of the volume is an exact multiple of the size of the array.
 		assert(m_volInput->getWidth() % arrayResult->getDimension(0) == 0);
@@ -74,7 +75,7 @@ namespace PolyVox
 		const Vector3DFloat v3dOffset(0.5f,0.5f,0.5f);
 
 		RaycastResult raycastResult;
-		Raycast<VolumeType, VoxelType> raycast(m_volInput, Vector3DFloat(0.0f,0.0f,0.0f), Vector3DFloat(1.0f,1.0f,1.0f), raycastResult);
+		Raycast<VolumeType, VoxelType> raycast(m_volInput, Vector3DFloat(0.0f,0.0f,0.0f), Vector3DFloat(1.0f,1.0f,1.0f), raycastResult, polyvox_bind(&PolyVox::AmbientOcclusionCalculator<VolumeType,VoxelType>::raycastCallback, this, std::placeholders::_1));
 
 		//This loop iterates over the bottom-lower-left voxel in each of the cells in the output array
 		for(uint16_t z = m_region.getLowerCorner().getZ(); z <= m_region.getUpperCorner().getZ(); z += iRatioZ)
@@ -131,4 +132,13 @@ namespace PolyVox
 			}
 		}
 	}
+
+	template< template<typename> class VolumeType, typename VoxelType>
+	//bool AmbientOcclusionCalculator<VolumeType, VoxelType>::raycastCallback(const typename VolumeType<VoxelType>::Sampler& sampler)
+	bool AmbientOcclusionCalculator<VolumeType, VoxelType>::raycastCallback(const typename SimpleVolume<VoxelType>::Sampler& sampler)
+	{
+		//VoxelType voxel = sampler.getVoxel();
+		//return m_funcIsTransparent(voxel);
+		return sampler.getVoxel().getMaterial() == 0;
+	}
 }