Work on generating surface patches on demand.

library/include/PolyVoxCore/IndexedSurfacePatch.h

@@ -54,6 +54,8 @@ namespace PolyVox
 
 	   Vector3DInt32 m_v3dRegionPosition; //FIXME - remove this?
 
+	   int32 m_iTimeStamp;
+	
 	private:		
 		std::vector<uint32> m_vecTriangleIndices;
 		std::vector<SurfaceVertex> m_vecVertices;

library/include/PolyVoxCore/Region.h

@@ -45,6 +45,8 @@ namespace PolyVox
 		bool containsPoint(const Vector3DInt32& pos, uint8 boundary) const;
 		void cropTo(const Region& other);
 		void shift(const Vector3DInt32& amount);
+		void shiftLowerCorner(const Vector3DInt32& amount);
+		void shiftUpperCorner(const Vector3DInt32& amount);
 
 	private:
 		Vector3DInt32 m_v3dLowerCorner;

library/include/PolyVoxUtil/VolumeChangeTracker.h

@@ -41,13 +41,16 @@ namespace PolyVox
 
 		//Getters
 		void getChangedRegions(std::list<Region>& listToFill) const;
+		int32 getCurrentTime(void) const;
 		Region getEnclosingRegion(void) const;		
+		int32 getLastModifiedTimeForRegion(uint16 uX, uint16 uY, uint16 uZ);
 		uint16 getSideLength(void);
 		BlockVolume<uint8>* getVolumeData(void) const;
 		uint8 getVoxelAt(const Vector3DUint16& pos);
 		uint8 getVoxelAt(uint16 uX, uint16 uY, uint16 uZ);
 
 		//Setters
+		void setAllRegionsModified(void);
 		void setAllRegionsUpToDate(bool newUpToDateValue);
 		void setLockedVoxelAt(uint16 x, uint16 y, uint16 z, uint8 value);		
 		void setVolumeData(BlockVolume<uint8>* volumeDataToSet);
@@ -63,6 +66,9 @@ namespace PolyVox
 		Region m_regLastLocked;
 		BlockVolume<uint8>* volumeData;
 		LinearVolume<bool>* volRegionUpToDate;
+		LinearVolume<int32>* volRegionLastModified;
+
+		static int32 m_iCurrentTime;
 	};
 }
 

library/source/PolyVoxCore/IndexedSurfacePatch.cpp

@@ -27,6 +27,7 @@ namespace PolyVox
 {
 	IndexedSurfacePatch::IndexedSurfacePatch()
 	{
+		m_iTimeStamp = -1;
 	}
 
 	IndexedSurfacePatch::~IndexedSurfacePatch()	  

library/source/PolyVoxCore/Region.cpp

@@ -69,4 +69,14 @@ namespace PolyVox
 		m_v3dLowerCorner += amount;
 		m_v3dUpperCorner += amount;
 	}
+
+	void Region::shiftLowerCorner(const Vector3DInt32& amount)
+	{
+		m_v3dLowerCorner += amount;
+	}
+
+	void Region::shiftUpperCorner(const Vector3DInt32& amount)
+	{
+		m_v3dUpperCorner += amount;
+	}
 }

library/source/PolyVoxUtil/VolumeChangeTracker.cpp

@@ -36,6 +36,7 @@ using namespace std;
 
 namespace PolyVox
 {
+	int32 VolumeChangeTracker::m_iCurrentTime = 0;
 
 	//////////////////////////////////////////////////////////////////////////
 	// VolumeChangeTracker
@@ -54,6 +55,7 @@ namespace PolyVox
 	{
 		volumeData = volumeDataToSet;
 		volRegionUpToDate = new LinearVolume<bool>(PolyVox::logBase2(POLYVOX_VOLUME_SIDE_LENGTH_IN_REGIONS));
+		volRegionLastModified = new LinearVolume<int32>(PolyVox::logBase2(POLYVOX_VOLUME_SIDE_LENGTH_IN_REGIONS));
 	}
 
 
@@ -106,6 +108,26 @@ namespace PolyVox
 		}
 	}
 
+	void VolumeChangeTracker::setAllRegionsModified(void)
+	{
+		for(uint16 blockZ = 0; blockZ < POLYVOX_VOLUME_SIDE_LENGTH_IN_REGIONS; ++blockZ)
+		{
+			for(uint16 blockY = 0; blockY < POLYVOX_VOLUME_SIDE_LENGTH_IN_REGIONS; ++blockY)
+			{
+				for(uint16 blockX = 0; blockX < POLYVOX_VOLUME_SIDE_LENGTH_IN_REGIONS; ++blockX)
+				{
+					volRegionLastModified->setVoxelAt(blockX, blockY, blockZ, m_iCurrentTime);
+					++m_iCurrentTime;
+				}
+			}
+		}
+	}
+
+	int32 VolumeChangeTracker::getCurrentTime(void) const
+	{
+		return m_iCurrentTime;
+	}
+
 	uint16 VolumeChangeTracker::getSideLength(void)
 	{
 		return volumeData->getSideLength();
@@ -116,6 +138,11 @@ namespace PolyVox
 		return volumeData->getEnclosingRegion();
 	}
 
+	int32 VolumeChangeTracker::getLastModifiedTimeForRegion(uint16 uX, uint16 uY, uint16 uZ)
+	{
+		return volRegionLastModified->getVoxelAt(uX, uY, uZ);
+	}
+
 	uint8 VolumeChangeTracker::getVoxelAt(const Vector3DUint16& pos)
 	{
 		return getVoxelAt(pos.getX(), pos.getY(), pos.getZ());
@@ -153,6 +180,7 @@ namespace PolyVox
 			(z % POLYVOX_REGION_SIDE_LENGTH != POLYVOX_REGION_SIDE_LENGTH-1))
 		{
 			volRegionUpToDate->setVoxelAt(x >> POLYVOX_REGION_SIDE_LENGTH_POWER, y >> POLYVOX_REGION_SIDE_LENGTH_POWER, z >> POLYVOX_REGION_SIDE_LENGTH_POWER, false);
+			volRegionLastModified->setVoxelAt(x >> POLYVOX_REGION_SIDE_LENGTH_POWER, y >> POLYVOX_REGION_SIDE_LENGTH_POWER, z >> POLYVOX_REGION_SIDE_LENGTH_POWER, m_iCurrentTime);
 		}
 		else //Mark surrounding regions as well
 		{
@@ -175,10 +203,12 @@ namespace PolyVox
 					for(uint16 xCt = minRegionX; xCt <= maxRegionX; xCt++)
 					{
 						volRegionUpToDate->setVoxelAt(xCt,yCt,zCt,false);
+						volRegionLastModified->setVoxelAt(xCt,yCt,zCt,m_iCurrentTime);
 					}
 				}
 			}
 		}
+		++m_iCurrentTime;
 	}
 
 	void VolumeChangeTracker::setLockedVoxelAt(uint16 x, uint16 y, uint16 z, uint8 value)
@@ -224,10 +254,12 @@ namespace PolyVox
 				for(uint16 xCt = firstRegionX; xCt <= lastRegionX; xCt++)
 				{
 					volRegionUpToDate->setVoxelAt(xCt,yCt,zCt,false);
+					volRegionLastModified->setVoxelAt(xCt,yCt,zCt,m_iCurrentTime);
 				}
 			}
 		}
 
+		++m_iCurrentTime;
 		m_bIsLocked = false;
 	}
 }