A PagedVolume must now always be provided with a Pager when it is constructed.

include/PolyVox/PagedVolume.h

@@ -249,7 +249,7 @@ namespace PolyVox
 
 	public:
 		/// Constructor for creating a fixed size volume.
-		PagedVolume(Pager* pPager = nullptr, uint32_t uTargetMemoryUsageInBytes = 256 * 1024 * 1024, uint16_t uChunkSideLength = 32);
+		PagedVolume(Pager* pPager, uint32_t uTargetMemoryUsageInBytes = 256 * 1024 * 1024, uint16_t uChunkSideLength = 32);
 		/// Destructor
 		~PagedVolume();
 
@@ -319,7 +319,7 @@ namespace PolyVox
 		uint8_t m_uChunkSideLengthPower;
 		int32_t m_iChunkMask;
 
-		Pager* m_pPager;
+		Pager* m_pPager = nullptr;
 	};
 }
 

include/PolyVox/PagedVolume.inl

@@ -41,6 +41,7 @@ namespace PolyVox
 		, m_uChunkSideLength(uChunkSideLength)
 	{
 		// Validation of parameters
+		POLYVOX_THROW_IF(!pPager, std::invalid_argument, "You must provide a valid pager when constructing a PagedVolume");
 		POLYVOX_THROW_IF(uTargetMemoryUsageInBytes < 1 * 1024 * 1024, std::invalid_argument, "Target memory usage is too small to be practical");
 		POLYVOX_THROW_IF(m_uChunkSideLength == 0, std::invalid_argument, "Chunk side length cannot be zero.");
 		POLYVOX_THROW_IF(m_uChunkSideLength > 256, std::invalid_argument, "Chunk size is too large to be practical.");
@@ -191,7 +192,7 @@ namespace PolyVox
 		// Ensure we don't page in more chunks than the volume can hold.
 		Region region(v3dStart, v3dEnd);
 		uint32_t uNoOfChunks = static_cast<uint32_t>(region.getWidthInVoxels() * region.getHeightInVoxels() * region.getDepthInVoxels());
-		POLYVOX_LOG_WARNING_IF(uNoOfChunks > m_uChunkCountLimit, "Attempting to prefetch more than the maximum number of chunks.");
+		POLYVOX_LOG_WARNING_IF(uNoOfChunks > m_uChunkCountLimit, "Attempting to prefetch more than the maximum number of chunks (this will cause thrashing).");
 		uNoOfChunks = (std::min)(uNoOfChunks, m_uChunkCountLimit);
 
 		// Loops over the specified positions and touch the corresponding chunks.
@@ -213,8 +214,6 @@ namespace PolyVox
 	template <typename VoxelType>
 	void PagedVolume<VoxelType>::flushAll()
 	{
-		POLYVOX_LOG_WARNING_IF(!m_pPager, "Data discarded by flush operation as no pager is attached.");
-
 		// Clear this pointer so it doesn't hang on to any chunks.
 		m_pLastAccessedChunk = nullptr;
 
@@ -234,8 +233,6 @@ namespace PolyVox
 	template <typename VoxelType>
 	void PagedVolume<VoxelType>::flush(Region regFlush)
 	{
-		POLYVOX_LOG_WARNING_IF(!m_pPager, "Data discarded by flush operation as no pager is attached.");
-
 		// Clear this pointer so it doesn't hang on to any chunks.
 		m_pLastAccessedChunk = nullptr;
 
@@ -329,10 +326,6 @@ namespace PolyVox
 			bool erasedChunk = false;
 			while (m_pRecentlyUsedChunks.size() + 1 > m_uChunkCountLimit) // +1 ready for new chunk we will add next.
 			{
-				// This should never hit, because it should not have been possible for
-				// the user to limit the number of chunks if they did not provide a pager.
-				POLYVOX_ASSERT(m_pPager, "A valid pager is required to limit number of chunks");
-
 				// Find the least recently used chunk. Hopefully this isn't too slow.
 				typename SharedPtrChunkMap::iterator itUnloadChunk = m_pRecentlyUsedChunks.begin();
 				for (typename SharedPtrChunkMap::iterator i = m_pRecentlyUsedChunks.begin(); i != m_pRecentlyUsedChunks.end(); i++)

include/PolyVox/PagedVolumeChunk.inl

@@ -35,6 +35,8 @@ namespace PolyVox
 		,m_pPager(pPager)
 		,m_v3dChunkSpacePosition(v3dPosition)
 	{
+		POLYVOX_ASSERT(m_pPager, "No valid pager supplied to chunk constructor.");
+
 		// Compute the side length               
 		m_uSideLength = uSideLength;
 		m_uSideLengthPower = logBase2(uSideLength);
@@ -44,8 +46,6 @@ namespace PolyVox
 		m_tData = new VoxelType[uNoOfVoxels];  
 
 		// Pass the chunk to the Pager to give it a chance to initialise it with any data
-		if (m_pPager)
-		{
 		// From the coordinates of the chunk we deduce the coordinates of the contained voxels.
 		Vector3DInt32 v3dLower = m_v3dChunkSpacePosition * static_cast<int32_t>(m_uSideLength);
 		Vector3DInt32 v3dUpper = v3dLower + Vector3DInt32(m_uSideLength - 1, m_uSideLength - 1, m_uSideLength - 1);
@@ -53,12 +53,6 @@ namespace PolyVox
 
 		// Page the data in
 		m_pPager->pageIn(reg, this);
-		}
-		else
-		{
-			// Just fill with zeros
-			std::fill(m_tData, m_tData + uNoOfVoxels, VoxelType());
-		}
 
 		// We'll use this later to decide if data needs to be paged out again.
 		m_bDataModified = false;
@@ -67,7 +61,7 @@ namespace PolyVox
 	template <typename VoxelType>
 	PagedVolume<VoxelType>::Chunk::~Chunk()
 	{
-		if (m_pPager && m_bDataModified)
+		if (m_bDataModified)
 		{
 			// From the coordinates of the chunk we deduce the coordinates of the contained voxels.
 			Vector3DInt32 v3dLower = m_v3dChunkSpacePosition * static_cast<int32_t>(m_uSideLength);

tests/TestCubicSurfaceExtractor.cpp

@@ -24,6 +24,7 @@ freely, subject to the following restrictions:
 #include "TestCubicSurfaceExtractor.h"
 
 #include "PolyVox/Density.h"
+#include "PolyVox/FilePager.h"
 #include "PolyVox/Material.h"
 #include "PolyVox/MaterialDensityPair.h"
 #include "PolyVox/RawVolume.h"
@@ -95,7 +96,8 @@ template <typename VolumeType>
 VolumeType* createAndFillVolumeRealistic(int32_t iVolumeSideLength)
 {
 	//Create empty volume
-	VolumeType* volData = new VolumeType;
+	FilePager<uint32_t>* filePager = new FilePager<uint32_t>();
+	VolumeType* volData = new VolumeType(filePager);
 
 	//Fill the volume with data
 	for (int32_t z = 0; z < iVolumeSideLength; z++)
@@ -158,7 +160,8 @@ void TestCubicSurfaceExtractor::testBehaviour()
 
 void TestCubicSurfaceExtractor::testEmptyVolumePerformance()
 {
-	PagedVolume<uint32_t> emptyVol;
+	FilePager<uint32_t>* filePager = new FilePager<uint32_t>();
+	PagedVolume<uint32_t> emptyVol(filePager);
 	createAndFillVolumeWithNoise(emptyVol, 128, 0, 0);
 	Mesh< CubicVertex< uint32_t >, uint16_t > emptyMesh;
 	QBENCHMARK{ extractCubicMeshCustom(&emptyVol, Region(32, 32, 32, 63, 63, 63), &emptyMesh); }
@@ -175,7 +178,8 @@ void TestCubicSurfaceExtractor::testRealisticVolumePerformance()
 
 void TestCubicSurfaceExtractor::testNoiseVolumePerformance()
 {
-	PagedVolume<uint32_t> noiseVol;
+	FilePager<uint32_t>* filePager = new FilePager<uint32_t>();
+	PagedVolume<uint32_t> noiseVol(filePager);
 	createAndFillVolumeWithNoise(noiseVol, 128, 0, 2);
 	Mesh< CubicVertex< uint32_t >, uint16_t > noiseMesh;
 	QBENCHMARK{ extractCubicMeshCustom(&noiseVol, Region(32, 32, 32, 63, 63, 63), &noiseMesh); }