Fast version of perlin noise.

examples/Basic/main.cpp

@@ -343,7 +343,7 @@ Perlin::Perlin(int octaves,float freq,float amp,int seed)
   mStart = true;
 }
 
-void createPerlinVolume(Volume<MaterialDensityPair44>& volData)
+void createPerlinVolumeSlow(Volume<MaterialDensityPair44>& volData)
 {
 	Perlin perlin(2,8,1,234);
 
@@ -374,6 +374,54 @@ void createPerlinVolume(Volume<MaterialDensityPair44>& volData)
 	}
 }
 
+void createPerlinVolumeFast(Volume<MaterialDensityPair44>& volData)
+{
+	Perlin perlin(2,8,1,234);
+
+	for(int blockZ = 0; blockZ < volData.m_uDepthInBlocks; blockZ++)
+	{		
+		std::cout << blockZ << std::endl;
+		for(int blockY = 0; blockY < volData.m_uHeightInBlocks; blockY++)
+		{
+			for(int blockX = 0; blockX < volData.m_uWidthInBlocks; blockX++)
+			{
+				for(int offsetz = 0; offsetz < volData.m_uBlockSideLength; offsetz++)
+				{
+					for(int offsety = 0; offsety < volData.m_uBlockSideLength; offsety++)
+					{
+						for(int offsetx = 0; offsetx < volData.m_uBlockSideLength; offsetx++) 
+						{							
+							int x = blockX * volData.m_uBlockSideLength + offsetx;
+							int y = blockY * volData.m_uBlockSideLength + offsety;
+							int z = blockZ * volData.m_uBlockSideLength + offsetz;
+
+							if((x == 0) || (x == volData.getWidth()-1)) continue;
+							if((y == 0) || (y == volData.getHeight()-1)) continue;
+							if((z == 0) || (z == volData.getDepth()-1)) continue;
+
+							float perlinVal = perlin.Get3D(x /static_cast<float>(volData.getWidth()-1), (y) / static_cast<float>(volData.getHeight()-1), z / static_cast<float>(volData.getDepth()-1));
+
+							MaterialDensityPair44 voxel;
+							if(perlinVal < 0.0f)
+							{
+								voxel.setMaterial(245);
+								voxel.setDensity(MaterialDensityPair44::getMaxDensity());
+							}
+							else
+							{
+								voxel.setMaterial(0);
+								voxel.setDensity(MaterialDensityPair44::getMinDensity());
+							}
+
+							volData.setVoxelAt(x, y, z, voxel);
+						}
+					}
+				}
+			}
+		}			
+	}
+}
+
 void createSphereInVolume(Volume<MaterialDensityPair44>& volData, Vector3DFloat v3dVolCenter, float fRadius)
 {
 	//This vector hold the position of the center of the volume
@@ -421,9 +469,9 @@ int main(int argc, char *argv[])
 	openGLWidget.show();
 
 	//Create an empty volume and then place a sphere in it
-	Volume<MaterialDensityPair44> volData(128, 128, 128);
+	Volume<MaterialDensityPair44> volData(1024, 1024, 1024);
 	//createSphereInVolume(volData, 30);
-	createPerlinVolume(volData);
+	createPerlinVolumeFast(volData);
 
 	/*srand(12345);
 	for(int ct = 0; ct < 1000; ct++)
@@ -439,12 +487,12 @@ int main(int argc, char *argv[])
 	}*/
 
 	//Extract the surface
-	SurfaceMesh<PositionMaterialNormal> mesh;
+	/*SurfaceMesh<PositionMaterialNormal> mesh;
 	CubicSurfaceExtractorWithNormals<MaterialDensityPair44> surfaceExtractor(&volData, volData.getEnclosingRegion(), &mesh);
 	surfaceExtractor.execute();
 
 	//Pass the surface to the OpenGL window
-	openGLWidget.setSurfaceMeshToRender(mesh);
+	openGLWidget.setSurfaceMeshToRender(mesh);*/
 
 	//Run the message pump.
 	return app.exec();

library/PolyVoxCore/include/PolyVoxImpl/Block.h

@@ -61,6 +61,7 @@ namespace PolyVox
 		uint8_t m_uSideLengthPower;	
 		VoxelType* m_tUncompressedData;
 		bool m_bIsCompressed;
+		bool m_bIsUncompressedDataModified;
 		uint64_t m_uTimestamp;
 
 		std::vector<uint8_t> runlengths;

library/PolyVoxCore/include/PolyVoxImpl/Block.inl

@@ -38,6 +38,7 @@ namespace PolyVox
 		,m_uSideLengthPower(0)
 		,m_tUncompressedData(0)
 		,m_bIsCompressed(true)
+		,m_bIsUncompressedDataModified(true)
 		,m_uTimestamp(0)
 	{
 		if(uSideLength != 0)
@@ -77,6 +78,7 @@ namespace PolyVox
 		m_uSideLength = rhs.m_uSideLength;
 		m_uSideLengthPower = rhs.m_uSideLengthPower;	
 		m_bIsCompressed = rhs.m_bIsCompressed;
+		m_bIsUncompressedDataModified = rhs.m_bIsUncompressedDataModified;
 		m_uTimestamp = rhs.m_uTimestamp;
 		runlengths = rhs.runlengths;
 		values = rhs.values;
@@ -134,6 +136,8 @@ namespace PolyVox
 			uYPos * m_uSideLength + 
 			uZPos * m_uSideLength * m_uSideLength
 		] = tValue;
+
+		m_bIsUncompressedDataModified = true;
 	}
 
 	template <typename VoxelType>
@@ -152,6 +156,8 @@ namespace PolyVox
 
 		const uint32_t uNoOfVoxels = m_uSideLength * m_uSideLength * m_uSideLength;
 		std::fill(m_tUncompressedData, m_tUncompressedData + uNoOfVoxels, tValue);
+
+		m_bIsUncompressedDataModified = true;
 	}
 
 	template <typename VoxelType>
@@ -180,6 +186,8 @@ namespace PolyVox
 			//If this fails an exception will be thrown. Memory is not   
 			//allocated and there is nothing else in this class to clean up
 			m_tUncompressedData = new VoxelType[m_uSideLength * m_uSideLength * m_uSideLength];
+
+			m_bIsUncompressedDataModified = true;
 		}
 	}
 
@@ -200,38 +208,43 @@ namespace PolyVox
 	template <typename VoxelType>
 	void Block<VoxelType>::compress(void)
 	{
-		uint32_t uNoOfVoxels = m_uSideLength * m_uSideLength * m_uSideLength;
-		runlengths.clear();
-		values.clear();
+		//If the uncompressed data hasn't actually been
+		//modified then we don't need to redo the compression.
+		if(m_bIsUncompressedDataModified)
+		{
+			uint32_t uNoOfVoxels = m_uSideLength * m_uSideLength * m_uSideLength;
+			runlengths.clear();
+			values.clear();
 
-		VoxelType current = m_tUncompressedData[0];
-		uint8_t runLength = 1;
+			VoxelType current = m_tUncompressedData[0];
+			uint8_t runLength = 1;
 
-		for(uint32_t ct = 1; ct < uNoOfVoxels; ++ct)
-		{		
-			VoxelType value = m_tUncompressedData[ct];
-			if((value == current) && (runLength < (std::numeric_limits<uint8_t>::max)()))
-			{
-				runLength++;
-			}
-			else
-			{
-				runlengths.push_back(runLength);
-				values.push_back(current);
-				current = value;
-				runLength = 1;
+			for(uint32_t ct = 1; ct < uNoOfVoxels; ++ct)
+			{		
+				VoxelType value = m_tUncompressedData[ct];
+				if((value == current) && (runLength < (std::numeric_limits<uint8_t>::max)()))
+				{
+					runLength++;
+				}
+				else
+				{
+					runlengths.push_back(runLength);
+					values.push_back(current);
+					current = value;
+					runLength = 1;
+				}
 			}
+
+			runlengths.push_back(runLength);
+			values.push_back(current);
+
+			//Shrink the vectors to their contents (seems slow?):
+			//http://stackoverflow.com/questions/1111078/reduce-the-capacity-of-an-stl-vector
+			//C++0x may have a shrink_to_fit() function?
+			//std::vector<uint8_t>(runlengths).swap(runlengths);
+			//std::vector<VoxelType>(values).swap(values);
 		}
 
-		runlengths.push_back(runLength);
-		values.push_back(current);
-
-		//Shrink the vectors to their contents (seems slow?):
-		//http://stackoverflow.com/questions/1111078/reduce-the-capacity-of-an-stl-vector
-		//C++0x may have a shrink_to_fit() function?
-		//std::vector<uint8_t>(runlengths).swap(runlengths);
-		//std::vector<VoxelType>(values).swap(values);
-
 		delete[] m_tUncompressedData;
 		m_tUncompressedData = 0;
 		m_bIsCompressed = true;
@@ -270,5 +283,6 @@ namespace PolyVox
 		}
 
 		m_bIsCompressed = false;
+		m_bIsUncompressedDataModified = false;
 	}
 }

library/PolyVoxCore/include/Volume.h

@@ -155,7 +155,7 @@ namespace PolyVox
 		///Resises the volume to the specified dimensions
 		void resize(uint16_t uWidth, uint16_t uHeight, uint16_t uDepth, uint16_t uBlockSideLength = 32);
 
-	private:
+	public:
 		Block<VoxelType>* getUncompressedBlock(Block<VoxelType>* block) const;
 
 		Block<VoxelType> m_pBorderBlock;