diff --git a/examples/OpenGL/OpenGLWidget.h b/examples/OpenGL/OpenGLWidget.h
index 35d67b19..f61a43ad 100644
--- a/examples/OpenGL/OpenGLWidget.h
+++ b/examples/OpenGL/OpenGLWidget.h
@@ -39,6 +39,22 @@ freely, subject to the following restrictions:
 
 const int32_t g_uVolumeSideLength = 128;
 
+struct Vector3DUint8Compare
+{
+    bool operator() (const PolyVox::Vector3DUint8& a, const PolyVox::Vector3DUint8& b)
+    {
+		const uint32_t size = 3;
+        for(uint32_t ct = 0; ct < size; ++ct)
+		{
+			if (a.getElement(ct) < b.getElement(ct))
+				return true;
+			if (b.getElement(ct) < a.getElement(ct))
+				return false;
+		}
+		return false;
+    }
+};
+
 class OpenGLWidget : public QGLWidget
  {
 
@@ -71,8 +87,8 @@ class OpenGLWidget : public QGLWidget
 	PolyVox::LargeVolume<PolyVox::MaterialDensityPair44>* m_volData;
 
 	//Rather than storing one big mesh, the volume is broken into regions and a mesh is stored for each region
-	std::map<PolyVox::Vector3DUint8, OpenGLSurfaceMesh> m_mapOpenGLSurfaceMeshes;
-	std::map<PolyVox::Vector3DUint8, polyvox_shared_ptr<PolyVox::SurfaceMesh<PolyVox::PositionMaterialNormal> > > m_mapSurfaceMeshes;
+	std::map<PolyVox::Vector3DUint8, OpenGLSurfaceMesh, Vector3DUint8Compare> m_mapOpenGLSurfaceMeshes;
+	std::map<PolyVox::Vector3DUint8, polyvox_shared_ptr<PolyVox::SurfaceMesh<PolyVox::PositionMaterialNormal> >, Vector3DUint8Compare> m_mapSurfaceMeshes;
 
 	unsigned int m_uRegionSideLength;
 	unsigned int m_uVolumeWidthInRegions;
diff --git a/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.h b/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.h
index 9c92e5ea..c0764527 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.h
+++ b/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.h
@@ -307,6 +307,22 @@ namespace PolyVox
 		LargeVolume& operator=(const LargeVolume& rhs);
 
 	private:
+
+		struct BlockPositionCompare
+		{
+			bool operator() (const PolyVox::Vector3DInt32& a, const PolyVox::Vector3DInt32& b)
+			{
+				const uint32_t size = 3;
+				for(uint32_t ct = 0; ct < size; ++ct)
+				{
+					if (a.getElement(ct) < b.getElement(ct))
+						return true;
+					if (b.getElement(ct) < a.getElement(ct))
+						return false;
+				}
+				return false;
+			}
+		};
 		void initialise(const Region& regValidRegion, uint16_t uBlockSideLength);
 
 		/// gets called when a new region is allocated and needs to be filled
@@ -320,12 +336,12 @@ namespace PolyVox
 		polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> m_funcDataOverflowHandler;
 	
 		Block<VoxelType>* getUncompressedBlock(int32_t uBlockX, int32_t uBlockY, int32_t uBlockZ) const;
-		void eraseBlock(typename std::map<Vector3DInt32, LoadedBlock >::iterator itBlock) const;
+		void eraseBlock(typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itBlock) const;
 		/// this function can be called by m_funcDataRequiredHandler without causing any weird effects
 		bool setVoxelAtConst(int32_t uXPos, int32_t uYPos, int32_t uZPos, VoxelType tValue) const;
 
 		//The block data
-		mutable std::map<Vector3DInt32, LoadedBlock > m_pBlocks;
+		mutable std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare> m_pBlocks;
 
 		//The cache of uncompressed blocks. The uncompressed block data and the timestamps are stored here rather
 		//than in the Block class. This is so that in the future each VolumeIterator might to maintain its own cache
diff --git a/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.inl b/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.inl
index 54df09c5..81d53a3f 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/LargeVolume.inl
@@ -297,7 +297,7 @@ namespace PolyVox
 				for(int32_t z = v3dStart.getZ(); z <= v3dEnd.getZ(); z++)
 				{
 					Vector3DInt32 pos(x,y,z);
-					typename std::map<Vector3DInt32, LoadedBlock>::iterator itBlock = m_pBlocks.find(pos);
+					typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itBlock = m_pBlocks.find(pos);
 					
 					if(itBlock != m_pBlocks.end())
 					{
@@ -328,7 +328,7 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::flushAll()
 	{
-		typename std::map<Vector3DInt32, LoadedBlock >::iterator i;
+		typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator i;
 		//Replaced the for loop here as the call to
 		//eraseBlock was invalidating the iterator.
 		while(m_pBlocks.size() > 0)
@@ -362,7 +362,7 @@ namespace PolyVox
 				for(int32_t z = v3dStart.getZ(); z <= v3dEnd.getZ(); z++)
 				{
 					Vector3DInt32 pos(x,y,z);
-					typename std::map<Vector3DInt32, LoadedBlock>::iterator itBlock = m_pBlocks.find(pos);
+					typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itBlock = m_pBlocks.find(pos);
 					if(itBlock == m_pBlocks.end())
 					{
 						// not loaded, not unloading
@@ -448,7 +448,7 @@ namespace PolyVox
 	}
 
 	template <typename VoxelType>
-	void LargeVolume<VoxelType>::eraseBlock(typename std::map<Vector3DInt32, LoadedBlock >::iterator itBlock) const
+	void LargeVolume<VoxelType>::eraseBlock(typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itBlock) const
 	{
 		if(m_funcDataOverflowHandler)
 		{
@@ -519,7 +519,7 @@ namespace PolyVox
 			return m_pLastAccessedBlock;
 		}		
 
-		typename std::map<Vector3DInt32, LoadedBlock >::iterator itBlock = m_pBlocks.find(v3dBlockPos);
+		typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itBlock = m_pBlocks.find(v3dBlockPos);
 		// check whether the block is already loaded
 		if(itBlock == m_pBlocks.end())
 		{
@@ -532,8 +532,8 @@ namespace PolyVox
 				if(m_pBlocks.size() == m_uMaxNumberOfBlocksInMemory)
 				{
 					// find the least recently used block
-					typename std::map<Vector3DInt32, LoadedBlock >::iterator i;
-					typename std::map<Vector3DInt32, LoadedBlock >::iterator itUnloadBlock = m_pBlocks.begin();
+					typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator i;
+					typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator itUnloadBlock = m_pBlocks.begin();
 					for(i = m_pBlocks.begin(); i != m_pBlocks.end(); i++)
 					{
 						if(i->second.timestamp < itUnloadBlock->second.timestamp)
@@ -636,7 +636,7 @@ namespace PolyVox
 		uint32_t uSizeInBytes = sizeof(LargeVolume);
 
 		//Memory used by the blocks
-		typename std::map<Vector3DInt32, LoadedBlock >::iterator i;
+		typename std::map<Vector3DInt32, LoadedBlock, BlockPositionCompare>::iterator i;
 		for(i = m_pBlocks.begin(); i != m_pBlocks.end(); i++)
 		{
 			//Inaccurate - account for rest of loaded block.