From 3010eb341dd1f7facab2a8f2afd36b762d46f3f6 Mon Sep 17 00:00:00 2001
From: David Williams <david@david-williams.info>
Date: Sat, 6 Jun 2009 23:08:08 +0000
Subject: [PATCH] Making use of sampling adjacent voxels. General optimisations
 and improvements.

---
 examples/OpenGL/main.cpp                      |  11 +
 library/PolyVoxCore/include/VolumeSampler.h   |  14 +-
 library/PolyVoxCore/include/VolumeSampler.inl | 286 ++++++++----------
 .../PolyVoxCore/source/GradientEstimators.cpp |   4 +-
 .../PolyVoxCore/source/SurfaceExtractor.cpp   |  37 ++-
 library/PolyVoxCore/source/VoxelFilters.cpp   |   6 +-
 library/PolyVoxUtil/source/Serialization.cpp  |   4 +-
 7 files changed, 174 insertions(+), 188 deletions(-)

diff --git a/examples/OpenGL/main.cpp b/examples/OpenGL/main.cpp
index 1014d3de..26032ce1 100644
--- a/examples/OpenGL/main.cpp
+++ b/examples/OpenGL/main.cpp
@@ -66,6 +66,17 @@ int main(int argc, char *argv[])
 	cout << "Creating sphere 5" << std::endl;
 	createSphereInVolume(volData, 20.0f, 1);
 
+	/*cout << "Creating sphere 1" << std::endl;
+	createSphereInVolume(volData, 120.0f, 5);
+	cout << "Creating sphere 2" << std::endl;
+	createSphereInVolume(volData, 100.0f, 4);
+	cout << "Creating sphere 3" << std::endl;
+	createSphereInVolume(volData, 80.0f, 3);
+	cout << "Creating sphere 4" << std::endl;
+	createSphereInVolume(volData, 60.0f, 2);
+	cout << "Creating sphere 5" << std::endl;
+	createSphereInVolume(volData, 40.0f, 1);*/
+
 	cout << "Creating cubes" << std::endl;
 	createCubeInVolume(volData, Vector3DUint16(minPos, minPos, minPos), Vector3DUint16(midPos-1, midPos-1, midPos-1), 0);
 	createCubeInVolume(volData, Vector3DUint16(midPos+1, midPos+1, minPos), Vector3DUint16(maxPos, maxPos, midPos-1), 0);
diff --git a/library/PolyVoxCore/include/VolumeSampler.h b/library/PolyVoxCore/include/VolumeSampler.h
index a56136e6..d2231b92 100644
--- a/library/PolyVoxCore/include/VolumeSampler.h
+++ b/library/PolyVoxCore/include/VolumeSampler.h
@@ -34,20 +34,16 @@ namespace PolyVox
 	class VolumeSampler
 	{
 	public:
-		VolumeSampler(Volume<VoxelType>& volume);
-		~VolumeSampler();		
+		VolumeSampler(Volume<VoxelType>* volume);
+		~VolumeSampler();
 
-		bool operator==(const VolumeSampler& rhs);
-		bool operator<(const VolumeSampler& rhs);
-		bool operator>(const VolumeSampler& rhs);
-		bool operator<=(const VolumeSampler& rhs);
-		bool operator>=(const VolumeSampler& rhs);
+		VolumeSampler<VoxelType>& operator=(const VolumeSampler<VoxelType>& rhs) throw();
 
 		uint16_t getPosX(void) const;
 		uint16_t getPosY(void) const;
 		uint16_t getPosZ(void) const;
 		VoxelType getSubSampledVoxel(uint8_t uLevel) const;
-		const Volume<VoxelType>& getVolume(void) const;
+		const Volume<VoxelType>* getVolume(void) const;
 		inline VoxelType getVoxel(void) const;			
 
 		void setPosition(const Vector3DInt16& v3dNewPos);
@@ -94,7 +90,7 @@ namespace PolyVox
 	private:
 
 		//The current volume
-		Volume<VoxelType>& mVolume;
+		Volume<VoxelType>* mVolume;
 
 		//The current position in the volume
 		uint16_t mXPosInVolume;
diff --git a/library/PolyVoxCore/include/VolumeSampler.inl b/library/PolyVoxCore/include/VolumeSampler.inl
index 913530b6..f4d33262 100644
--- a/library/PolyVoxCore/include/VolumeSampler.inl
+++ b/library/PolyVoxCore/include/VolumeSampler.inl
@@ -32,7 +32,7 @@ namespace PolyVox
 {
 	#pragma region Constructors/Destructors
 	template <typename VoxelType>
-	VolumeSampler<VoxelType>::VolumeSampler(Volume<VoxelType>& volume)
+	VolumeSampler<VoxelType>::VolumeSampler(Volume<VoxelType>* volume)
 		:mVolume(volume)
 	{
 	}
@@ -45,64 +45,18 @@ namespace PolyVox
 
 	#pragma region Operators
 	template <typename VoxelType>
-	bool VolumeSampler<VoxelType>::operator==(const VolumeSampler<VoxelType>& rhs)
+	VolumeSampler<VoxelType>& VolumeSampler<VoxelType>::operator=(const VolumeSampler<VoxelType>& rhs) throw()
 	{
-		//We could just check whether the two mCurrentVoxel pointers are equal, but this may not
-		//be safe in the future if we decide to allow blocks to be shared between volumes
-		//So we really check whether the positions are the same.
-		//NOTE: With all iterator comparisons it is the users job to ensure they at least point
-		//to the same volume. Otherwise they are not comparible.
-		assert(&mVolume == &rhs.mVolume);
-		return
-		(
-			(mXPosInVolume == rhs.mXPosInVolume) &&
-			(mYPosInVolume == rhs.mYPosInVolume) &&
-			(mZPosInVolume == rhs.mZPosInVolume)
-		);
-	}
-
-	template <typename VoxelType>
-	bool VolumeSampler<VoxelType>::operator<(const VolumeSampler<VoxelType>& rhs)
-	{
-		assert(&mVolume == &rhs.mVolume);
-
-		if(mZPosInVolume < rhs.mZPosInVolume)
-			return true;
-		if(mZPosInVolume > rhs.mZPosInVolume)
-			return false;
-
-		if(mYPosInVolume < rhs.mYPosInVolume)
-			return true;
-		if(mYPosInVolume > rhs.mYPosInVolume)
-			return false;
-
-		if(mXPosInVolume < rhs.mXPosInVolume)
-			return true;
-		if(mXPosInVolume > rhs.mXPosInVolume)
-			return false;
-
-		return false;
-	}
-
-	template <typename VoxelType>
-	bool VolumeSampler<VoxelType>::operator>(const VolumeSampler<VoxelType>& rhs)
-	{
-		assert(&mVolume == &rhs.mVolume);
-		return (rhs < *this);
-	}
-
-	template <typename VoxelType>
-	bool VolumeSampler<VoxelType>::operator<=(const VolumeSampler<VoxelType>& rhs)
-	{
-		assert(&mVolume == &rhs.mVolume);
-		return (rhs > *this);
-	}
-
-	template <typename VoxelType>
-	bool VolumeSampler<VoxelType>::operator>=(const VolumeSampler<VoxelType>& rhs)
-	{
-		assert(&mVolume == &rhs.mVolume);
-		return (rhs < *this);
+		if(this == &rhs)
+		{
+			return *this;
+		}
+        mVolume = rhs.mVolume;
+		mXPosInVolume = rhs.mXPosInVolume;
+		mYPosInVolume = rhs.mYPosInVolume;
+		mZPosInVolume = rhs.mZPosInVolume;
+		mCurrentVoxel = rhs.mCurrentVoxel;
+        return *this;
 	}
 	#pragma endregion
 
@@ -155,7 +109,7 @@ namespace PolyVox
 				{
 					for(uint8_t x = 0; x < uSize; ++x)
 					{
-						tValue = (std::min)(tValue, mVolume.getVoxelAt(mXPosInVolume + x, mYPosInVolume + y, mZPosInVolume + z));
+						tValue = (std::min)(tValue, mVolume->getVoxelAt(mXPosInVolume + x, mYPosInVolume + y, mZPosInVolume + z));
 					}
 				}
 			}
@@ -164,7 +118,7 @@ namespace PolyVox
 	}
 
 	template <typename VoxelType>
-	const Volume<VoxelType>& VolumeSampler<VoxelType>::getVolume(void) const
+	const Volume<VoxelType>* VolumeSampler<VoxelType>::getVolume(void) const
 	{
 		return mVolume;
 	}
@@ -190,22 +144,22 @@ namespace PolyVox
 		mYPosInVolume = yPos;
 		mZPosInVolume = zPos;
 
-		const uint16_t uXBlock = mXPosInVolume >> mVolume.m_uBlockSideLengthPower;
-		const uint16_t uYBlock = mYPosInVolume >> mVolume.m_uBlockSideLengthPower;
-		const uint16_t uZBlock = mZPosInVolume >> mVolume.m_uBlockSideLengthPower;
+		const uint16_t uXBlock = mXPosInVolume >> mVolume->m_uBlockSideLengthPower;
+		const uint16_t uYBlock = mYPosInVolume >> mVolume->m_uBlockSideLengthPower;
+		const uint16_t uZBlock = mZPosInVolume >> mVolume->m_uBlockSideLengthPower;
 
-		const uint16_t uXPosInBlock = mXPosInVolume - (uXBlock << mVolume.m_uBlockSideLengthPower);
-		const uint16_t uYPosInBlock = mYPosInVolume - (uYBlock << mVolume.m_uBlockSideLengthPower);
-		const uint16_t uZPosInBlock = mZPosInVolume - (uZBlock << mVolume.m_uBlockSideLengthPower);
+		const uint16_t uXPosInBlock = mXPosInVolume - (uXBlock << mVolume->m_uBlockSideLengthPower);
+		const uint16_t uYPosInBlock = mYPosInVolume - (uYBlock << mVolume->m_uBlockSideLengthPower);
+		const uint16_t uZPosInBlock = mZPosInVolume - (uZBlock << mVolume->m_uBlockSideLengthPower);
 
 		const uint32_t uBlockIndexInVolume = uXBlock + 
-			uYBlock * mVolume.m_uWidthInBlocks + 
-			uZBlock * mVolume.m_uWidthInBlocks * mVolume.m_uHeightInBlocks;
-		const POLYVOX_SHARED_PTR< Block<VoxelType> >& currentBlock = mVolume.m_pBlocks[uBlockIndexInVolume];
+			uYBlock * mVolume->m_uWidthInBlocks + 
+			uZBlock * mVolume->m_uWidthInBlocks * mVolume->m_uHeightInBlocks;
+		const POLYVOX_SHARED_PTR< Block<VoxelType> >& currentBlock = mVolume->m_pBlocks[uBlockIndexInVolume];
 
 		const uint32_t uVoxelIndexInBlock = uXPosInBlock + 
-			uYPosInBlock * mVolume.m_uBlockSideLength + 
-			uZPosInBlock * mVolume.m_uBlockSideLength * mVolume.m_uBlockSideLength;
+			uYPosInBlock * mVolume->m_uBlockSideLength + 
+			uZPosInBlock * mVolume->m_uBlockSideLength * mVolume->m_uBlockSideLength;
 		mCurrentVoxel = currentBlock->m_tData + uVoxelIndexInBlock;
 	}
 	#pragma endregion
@@ -214,10 +168,10 @@ namespace PolyVox
 	template <typename VoxelType>
 	void VolumeSampler<VoxelType>::movePositiveX(void)
 	{
-		assert(mXPosInVolume < mVolume.m_uWidth - 1);
+		assert(mXPosInVolume < mVolume->m_uWidth - 1);
 
-		//Note the *post* increament here
-		if((mXPosInVolume++) % mVolume.m_uBlockSideLength == 0)
+		//Note the *pre* increament here
+		if((++mXPosInVolume) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
 			++mCurrentVoxel;			
@@ -232,13 +186,13 @@ namespace PolyVox
 	template <typename VoxelType>
 	void VolumeSampler<VoxelType>::movePositiveY(void)
 	{
-		assert(mYPosInVolume < mVolume.m_uHeight - 1);
+		assert(mYPosInVolume < mVolume->m_uHeight - 1);
 
-		//Note the *post* increament here
-		if((mYPosInVolume++) % mVolume.m_uBlockSideLength == 0)
+		//Note the *pre* increament here
+		if((++mYPosInVolume) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
-			mCurrentVoxel += mVolume.m_uBlockSideLength;
+			mCurrentVoxel += mVolume->m_uBlockSideLength;
 		}
 		else
 		{
@@ -250,13 +204,13 @@ namespace PolyVox
 	template <typename VoxelType>
 	void VolumeSampler<VoxelType>::movePositiveZ(void)
 	{
-		assert(mZPosInVolume < mVolume.m_uDepth - 1);
+		assert(mZPosInVolume < mVolume->m_uDepth - 1);
 
-		//Note the *post* increament here
-		if((mZPosInVolume++) % mVolume.m_uBlockSideLength == 0)
+		//Note the *pre* increament here
+		if((++mZPosInVolume) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
-			mCurrentVoxel += mVolume.m_uBlockSideLength * mVolume.m_uBlockSideLength;
+			mCurrentVoxel += mVolume->m_uBlockSideLength * mVolume->m_uBlockSideLength;
 		}
 		else
 		{
@@ -270,8 +224,8 @@ namespace PolyVox
 	{
 		assert(mXPosInVolume > 0);
 
-		//Note the *pre* increament here
-		if((--mXPosInVolume) % mVolume.m_uBlockSideLength == 0)
+		//Note the *post* increament here
+		if((mXPosInVolume--) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
 			++mCurrentVoxel;			
@@ -288,11 +242,11 @@ namespace PolyVox
 	{
 		assert(mYPosInVolume > 0);
 
-		//Note the *pre* increament here
-		if((--mYPosInVolume) % mVolume.m_uBlockSideLength == 0)
+		//Note the *post* increament here
+		if((mYPosInVolume--) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
-			mCurrentVoxel += mVolume.m_uBlockSideLength;
+			mCurrentVoxel += mVolume->m_uBlockSideLength;
 		}
 		else
 		{
@@ -306,11 +260,11 @@ namespace PolyVox
 	{
 		assert(mZPosInVolume > 0);
 
-		//Note the *pre* increament here
-		if((--mZPosInVolume) % mVolume.m_uBlockSideLength == 0)
+		//Note the *post* increament here
+		if((mZPosInVolume--) % mVolume->m_uBlockSideLength != 0)
 		{
 			//No need to compute new block.
-			mCurrentVoxel += mVolume.m_uBlockSideLength * mVolume.m_uBlockSideLength;
+			mCurrentVoxel += mVolume->m_uBlockSideLength * mVolume->m_uBlockSideLength;
 		}
 		else
 		{
@@ -324,91 +278,91 @@ namespace PolyVox
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1ny1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - 1 - mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 - mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1ny0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - 1 - mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 - mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1ny1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel - 1 - mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 - mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume-1,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx0py1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - 1 - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx0py0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
 			return *(mCurrentVoxel - 1);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx0py1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel - 1 + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1py1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - 1 + mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 + mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1py0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel - 1 + mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 + mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1nx1py1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != 0) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != 0) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel - 1 + mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - 1 + mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume-1,mYPosInVolume+1,mZPosInVolume+1);
 	}
 
 	//////////////////////////////////////////////////////////////////////////
@@ -416,41 +370,41 @@ namespace PolyVox
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1ny1nz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1ny0pz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1ny1pz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel - mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume-1,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px0py1nz(void) const
 	{
-		if((mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
@@ -462,41 +416,41 @@ namespace PolyVox
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px0py1pz(void) const
 	{
-		if((mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1py1nz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel + mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1py0pz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel0px1py1pz(void) const
 	{
-		if((mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume,mYPosInVolume+1,mZPosInVolume+1);
 	}
 
 	//////////////////////////////////////////////////////////////////////////
@@ -504,91 +458,91 @@ namespace PolyVox
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1ny1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel + 1 - mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 - mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1ny0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel + 1 - mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 - mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1ny1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != 0) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != 0) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + 1 - mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 - mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume-1,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px0py1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel + 1 - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px0py0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
 			return *(mCurrentVoxel + 1);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px0py1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + 1 + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume,mZPosInVolume+1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1py1nz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != 0))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != 0))
 		{
-			return *(mCurrentVoxel + 1 + mVolume.m_uBlockSideLength - mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 + mVolume->m_uBlockSideLength - mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume-1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume-1);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1py0pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + 1 + mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 + mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume);
 	}
 
 	template <typename VoxelType>
 	VoxelType VolumeSampler<VoxelType>::peekVoxel1px1py1pz(void) const
 	{
-		if((mXPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mYPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1) && (mZPosInVolume%mVolume.m_uBlockSideLength != mVolume.m_uBlockSideLength-1))
+		if((mXPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mYPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1) && (mZPosInVolume%mVolume->m_uBlockSideLength != mVolume->m_uBlockSideLength-1))
 		{
-			return *(mCurrentVoxel + 1 + mVolume.m_uBlockSideLength + mVolume.m_uBlockSideLength*mVolume.m_uBlockSideLength);
+			return *(mCurrentVoxel + 1 + mVolume->m_uBlockSideLength + mVolume->m_uBlockSideLength*mVolume->m_uBlockSideLength);
 		}
-		return mVolume.getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume+1);
+		return mVolume->getVoxelAt(mXPosInVolume+1,mYPosInVolume+1,mZPosInVolume+1);
 	}
 	#pragma endregion
 }
diff --git a/library/PolyVoxCore/source/GradientEstimators.cpp b/library/PolyVoxCore/source/GradientEstimators.cpp
index 1d151a42..9ae4dbe0 100644
--- a/library/PolyVoxCore/source/GradientEstimators.cpp
+++ b/library/PolyVoxCore/source/GradientEstimators.cpp
@@ -16,7 +16,7 @@ namespace PolyVox
 			const Vector3DFloat& v3dPos = iterSurfaceVertex->getPosition() + static_cast<Vector3DFloat>(isp.m_Region.getLowerCorner());
 			const Vector3DInt16 v3dFloor = static_cast<Vector3DInt16>(v3dPos);
 
-			VolumeSampler<uint8_t> volIter(*volumeData);
+			VolumeSampler<uint8_t> volIter(volumeData);
 
 			//Check all corners are within the volume, allowing a boundary for gradient estimation
 			bool lowerCornerInside = volumeData->getEnclosingRegion().containsPoint(v3dFloor,2);
@@ -42,7 +42,7 @@ namespace PolyVox
 	{
 		Vector3DFloat v3dGradient; //To store the result
 
-		VolumeSampler<uint8_t> volIter(*volumeData);
+		VolumeSampler<uint8_t> volIter(volumeData);
 
 			const Vector3DInt32 v3dFloor = static_cast<Vector3DInt32>(v3dPos);
 
diff --git a/library/PolyVoxCore/source/SurfaceExtractor.cpp b/library/PolyVoxCore/source/SurfaceExtractor.cpp
index 27795e33..775a016a 100644
--- a/library/PolyVoxCore/source/SurfaceExtractor.cpp
+++ b/library/PolyVoxCore/source/SurfaceExtractor.cpp
@@ -9,7 +9,7 @@ namespace PolyVox
 	SurfaceExtractor::SurfaceExtractor(Volume<uint8_t>& volData)
 		:m_uLodLevel(0)
 		,m_volData(volData)
-		,m_sampVolume(volData)
+		,m_sampVolume(&volData)
 	{
 	}
 
@@ -184,35 +184,62 @@ namespace PolyVox
 
 		//Process the edge where x is minimal.
 		uXVolSpace = m_regSliceCurrent.getLowerCorner().getX();
+		m_sampVolume.setPosition(uXVolSpace, m_regSliceCurrent.getLowerCorner().getY(), uZVolSpace);
 		for(uYVolSpace = m_regSliceCurrent.getLowerCorner().getY() + m_uStepSize; uYVolSpace <= uMaxYVolSpace; uYVolSpace += m_uStepSize)
 		{
 			uXRegSpace = uXVolSpace - m_regInputCropped.getLowerCorner().getX();
 			uYRegSpace = uYVolSpace - m_regInputCropped.getLowerCorner().getY();
 
-			m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
+			if(uLodLevel == 0)
+			{
+				m_sampVolume.movePositiveY();
+			}
+			else
+			{
+				m_sampVolume.setPosition(uXVolSpace, uYVolSpace, uZVolSpace);
+			}
+
 			computeBitmaskForCell<false, true, isPrevZAvail, uLodLevel>();
 		}
 
 		//Process the edge where y is minimal.
 		uYVolSpace = m_regSliceCurrent.getLowerCorner().getY();
+		m_sampVolume.setPosition(m_regSliceCurrent.getLowerCorner().getX(), uYVolSpace, uZVolSpace);
 		for(uXVolSpace = m_regSliceCurrent.getLowerCorner().getX() + m_uStepSize; uXVolSpace <= uMaxXVolSpace; uXVolSpace += m_uStepSize)
 		{	
 			uXRegSpace = uXVolSpace - m_regInputCropped.getLowerCorner().getX();
 			uYRegSpace = uYVolSpace - m_regInputCropped.getLowerCorner().getY();
 
-			m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
+			if(uLodLevel == 0)
+			{
+				m_sampVolume.movePositiveX();
+			}
+			else
+			{
+				m_sampVolume.setPosition(uXVolSpace, uYVolSpace, uZVolSpace);
+			}
+
 			computeBitmaskForCell<true, false, isPrevZAvail, uLodLevel>();
 		}
 
 		//Process all remaining elemnents of the slice. In this case, previous x and y values are always available
 		for(uYVolSpace = m_regSliceCurrent.getLowerCorner().getY() + m_uStepSize; uYVolSpace <= uMaxYVolSpace; uYVolSpace += m_uStepSize)
 		{
+			m_sampVolume.setPosition(m_regSliceCurrent.getLowerCorner().getX(), uYVolSpace, uZVolSpace);
 			for(uXVolSpace = m_regSliceCurrent.getLowerCorner().getX() + m_uStepSize; uXVolSpace <= uMaxXVolSpace; uXVolSpace += m_uStepSize)
 			{	
 				uXRegSpace = uXVolSpace - m_regInputCropped.getLowerCorner().getX();
 				uYRegSpace = uYVolSpace - m_regInputCropped.getLowerCorner().getY();
 
-				m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
+				if(uLodLevel == 0)
+				{
+					m_sampVolume.movePositiveX();
+				}
+				else
+				{
+					m_sampVolume.setPosition(uXVolSpace, uYVolSpace, uZVolSpace);
+				}
+
 				computeBitmaskForCell<true, true, isPrevZAvail, uLodLevel>();
 			}
 		}
@@ -274,7 +301,6 @@ namespace PolyVox
 					{
 						v011 = m_sampVolume.peekVoxel0px1py1pz();
 						v111 = m_sampVolume.peekVoxel1px1py1pz();
-
 					}
 					else
 					{
@@ -307,7 +333,6 @@ namespace PolyVox
 					{
 						v101 = m_sampVolume.peekVoxel1px0py1pz();
 						v111 = m_sampVolume.peekVoxel1px1py1pz();
-
 					}
 					else
 					{
diff --git a/library/PolyVoxCore/source/VoxelFilters.cpp b/library/PolyVoxCore/source/VoxelFilters.cpp
index f3a21c25..eb9fd935 100644
--- a/library/PolyVoxCore/source/VoxelFilters.cpp
+++ b/library/PolyVoxCore/source/VoxelFilters.cpp
@@ -9,9 +9,9 @@ namespace PolyVox
 		assert(volIter.getPosX() >= 1);
 		assert(volIter.getPosY() >= 1);
 		assert(volIter.getPosZ() >= 1);
-		assert(volIter.getPosX() <= volIter.getVolume().getWidth() - 2);
-		assert(volIter.getPosY() <= volIter.getVolume().getHeight() - 2);
-		assert(volIter.getPosZ() <= volIter.getVolume().getDepth() - 2);
+		assert(volIter.getPosX() <= volIter.getVolume()->getWidth() - 2);
+		assert(volIter.getPosY() <= volIter.getVolume()->getHeight() - 2);
+		assert(volIter.getPosZ() <= volIter.getVolume()->getDepth() - 2);
 
 		float sum = 0.0;
 
diff --git a/library/PolyVoxUtil/source/Serialization.cpp b/library/PolyVoxUtil/source/Serialization.cpp
index 0c08a359..651c4bdb 100644
--- a/library/PolyVoxUtil/source/Serialization.cpp
+++ b/library/PolyVoxUtil/source/Serialization.cpp
@@ -61,7 +61,7 @@ namespace PolyVox
 		stream.write(reinterpret_cast<char*>(&volumeDepthPower), sizeof(volumeDepthPower));
 
 		//Write data
-		VolumeSampler<uint8_t> volIter(volume);
+		VolumeSampler<uint8_t> volIter(&volume);
 		for(uint16_t z = 0; z < volumeDepth; ++z)
 		{
 			for(uint16_t y = 0; y < volumeHeight; ++y)
@@ -143,7 +143,7 @@ namespace PolyVox
 		stream.write(reinterpret_cast<char*>(&volumeDepthPower), sizeof(volumeDepthPower));
 
 		//Write data
-		VolumeSampler<uint8_t> volIter(volume);
+		VolumeSampler<uint8_t> volIter(&volume);
 		uint8_t current = 0;
 		uint32_t runLength = 0;
 		bool firstTime = true;