diff --git a/library/PolyVoxCore/include/PolyVoxCore/LargeVolumeSampler.inl b/library/PolyVoxCore/include/PolyVoxCore/LargeVolumeSampler.inl
index 3434d099..530fafc0 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/LargeVolumeSampler.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/LargeVolumeSampler.inl
@@ -148,11 +148,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::movePositiveX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::movePositiveX();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mXPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mXPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			++mCurrentVoxel;			
@@ -167,11 +170,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::movePositiveY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::movePositiveY();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mYPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mYPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel += this->mVolume->m_uBlockSideLength;
@@ -186,11 +192,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::movePositiveZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::movePositiveZ();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mZPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mZPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel += this->mVolume->m_uBlockSideLength * this->mVolume->m_uBlockSideLength;
@@ -205,11 +214,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::moveNegativeX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::moveNegativeX();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mXPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mXPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			--mCurrentVoxel;			
@@ -224,11 +236,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::moveNegativeY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::moveNegativeY();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mYPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mYPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel -= this->mVolume->m_uBlockSideLength;
@@ -243,11 +258,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void LargeVolume<VoxelType>::Sampler::moveNegativeZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> >::moveNegativeZ();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mZPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mZPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel -= this->mVolume->m_uBlockSideLength * this->mVolume->m_uBlockSideLength;
diff --git a/library/PolyVoxCore/include/PolyVoxCore/RawVolumeSampler.inl b/library/PolyVoxCore/include/PolyVoxCore/RawVolumeSampler.inl
index a2dfb9dc..866a2f64 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/RawVolumeSampler.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/RawVolumeSampler.inl
@@ -105,11 +105,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::movePositiveX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::movePositiveX();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			++mCurrentVoxel;
 		}
@@ -122,11 +125,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::movePositiveY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::movePositiveY();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			mCurrentVoxel += this->mVolume->getWidth();
 		}
@@ -139,11 +145,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::movePositiveZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::movePositiveZ();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			mCurrentVoxel += this->mVolume->getWidth() * this->mVolume->getHeight();
 		}
@@ -156,11 +165,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::moveNegativeX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::moveNegativeX();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			--mCurrentVoxel;
 		}
@@ -173,11 +185,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::moveNegativeY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::moveNegativeY();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			mCurrentVoxel -= this->mVolume->getWidth();
 		}
@@ -190,11 +205,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void RawVolume<VoxelType>::Sampler::moveNegativeZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< RawVolume<VoxelType> >::moveNegativeZ();
 
 		// Then we update the voxel pointer
-		if(this->isCurrentPositionValid() && mCurrentVoxel )
+		if(this->isCurrentPositionValid() && bIsOldPositionValid )
 		{
 			mCurrentVoxel -= this->mVolume->getWidth() * this->mVolume->getHeight();
 		}
diff --git a/library/PolyVoxCore/include/PolyVoxCore/SimpleVolumeSampler.inl b/library/PolyVoxCore/include/PolyVoxCore/SimpleVolumeSampler.inl
index 3893df22..7920fc6b 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/SimpleVolumeSampler.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/SimpleVolumeSampler.inl
@@ -167,11 +167,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::movePositiveX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::movePositiveX();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mXPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mXPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			++mCurrentVoxel;			
@@ -186,11 +189,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::movePositiveY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::movePositiveY();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mYPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mYPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel += this->mVolume->m_uBlockSideLength;
@@ -205,11 +211,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::movePositiveZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::movePositiveZ();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mZPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mZPosInVolume) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel += this->mVolume->m_uBlockSideLength * this->mVolume->m_uBlockSideLength;
@@ -224,11 +233,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::moveNegativeX(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::moveNegativeX();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mXPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mXPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			--mCurrentVoxel;			
@@ -243,11 +255,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::moveNegativeY(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::moveNegativeY();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mYPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mYPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel -= this->mVolume->m_uBlockSideLength;
@@ -262,11 +277,14 @@ namespace PolyVox
 	template <typename VoxelType>
 	void SimpleVolume<VoxelType>::Sampler::moveNegativeZ(void)
 	{
+		// We'll need this in a moment...
+		bool bIsOldPositionValid = this->isCurrentPositionValid();
+
 		// Base version updates position and validity flags.
 		BaseVolume<VoxelType>::template Sampler< SimpleVolume<VoxelType> >::moveNegativeZ();
 
 		// Then we update the voxel pointer
-		if((this->isCurrentPositionValid()) && mCurrentVoxel && ((this->mZPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
+		if((this->isCurrentPositionValid()) && bIsOldPositionValid && ((this->mZPosInVolume + 1) % this->mVolume->m_uBlockSideLength != 0))
 		{
 			//No need to compute new block.
 			mCurrentVoxel -= this->mVolume->m_uBlockSideLength * this->mVolume->m_uBlockSideLength;