From 4f9c93a454e76a37f3446d4ccaa88cb819a7c145 Mon Sep 17 00:00:00 2001
From: David Williams <david@david-williams.info>
Date: Wed, 3 Jun 2009 21:48:26 +0000
Subject: [PATCH] Work on templatizing surface extractor.

---
 examples/OpenGL/OpenGLWidget.cpp              |  2 +-
 .../PolyVoxCore/include/SurfaceExtractor.h    | 14 ++++++--
 .../PolyVoxCore/source/SurfaceExtractor.cpp   | 35 +++++++++++++------
 3 files changed, 37 insertions(+), 14 deletions(-)

diff --git a/examples/OpenGL/OpenGLWidget.cpp b/examples/OpenGL/OpenGLWidget.cpp
index 42023770..efa11726 100644
--- a/examples/OpenGL/OpenGLWidget.cpp
+++ b/examples/OpenGL/OpenGLWidget.cpp
@@ -38,7 +38,7 @@ void OpenGLWidget::setVolume(PolyVox::Volume<PolyVox::uint8_t>* volData)
 		m_uVolumeDepthInRegions = volData->getDepth() / m_uRegionSideLength;
 
 		SurfaceExtractor surfaceExtractor(*volData);
-		surfaceExtractor.setLodLevel(0);
+		surfaceExtractor.setLodLevel(1);
 
 		//Our volume is broken down into cuboid regions, and we create one mesh for each region.
 		//This three-level for loop iterates over each region.
diff --git a/library/PolyVoxCore/include/SurfaceExtractor.h b/library/PolyVoxCore/include/SurfaceExtractor.h
index b6ecc5fe..98dd30f9 100644
--- a/library/PolyVoxCore/include/SurfaceExtractor.h
+++ b/library/PolyVoxCore/include/SurfaceExtractor.h
@@ -92,12 +92,20 @@ namespace PolyVox
 		Region regSlice1;
 
 		uint16_t m_uRegionWidth;
+		//uint16_t m_uRegionWidthOverStepSize;
+		//uint16_t m_uRegionHeightOverStepSize;
 
 		//void extractSurfaceForRegionLevel0(Volume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* m_ispCurrent);
 
-		void extractSurfaceImpl(Region region, uint8_t uLodLevel);
-		uint32_t computeBitmaskForSlice(bool isPrevZAvail, uint8_t uLodLevel);
-		void computeBitmaskForCell(bool isPrevXAvail, bool isPrevYAvail, bool isPrevZAvail, uint8_t uLodLevel);
+		template<uint8_t uLodLevel>
+		void extractSurfaceImpl(Region region);
+
+		template<bool isPrevZAvail, uint8_t uLodLevel>
+		uint32_t computeBitmaskForSlice(void);
+
+		template<bool isPrevXAvail, bool isPrevYAvail, bool isPrevZAvail, uint8_t uLodLevel>
+		void computeBitmaskForCell(void);
+
 		void generateIndicesForSlice();
 		void generateVerticesForSlice();
 	};
diff --git a/library/PolyVoxCore/source/SurfaceExtractor.cpp b/library/PolyVoxCore/source/SurfaceExtractor.cpp
index 548c140a..4965ed1f 100644
--- a/library/PolyVoxCore/source/SurfaceExtractor.cpp
+++ b/library/PolyVoxCore/source/SurfaceExtractor.cpp
@@ -31,14 +31,27 @@ namespace PolyVox
 		//POLYVOX_SHARED_PTR<IndexedSurfacePatch> result(new IndexedSurfacePatch());
 		m_ispCurrent = new IndexedSurfacePatch();
 
-		extractSurfaceImpl(region, m_uLodLevel);
+		switch(m_uLodLevel)
+		{
+		case 0:
+			extractSurfaceImpl<0>(region);
+			break;
+		case 1:
+			extractSurfaceImpl<1>(region);
+			break;
+		case 2:
+			extractSurfaceImpl<2>(region);
+			break;
+		}
+		
 
 		m_ispCurrent->m_Region = region;
 
 		return POLYVOX_SHARED_PTR<IndexedSurfacePatch>(m_ispCurrent);
 	}
 
-	void SurfaceExtractor::extractSurfaceImpl(Region region, uint8_t uLodLevel)
+	template<uint8_t uLodLevel>
+	void SurfaceExtractor::extractSurfaceImpl(Region region)
 	{	
 		m_ispCurrent->clear();
 
@@ -80,7 +93,7 @@ namespace PolyVox
 		uint32_t uNoOfNonEmptyCellsForSlice1 = 0;
 
 		//Process the first slice (previous slice not available)
-		computeBitmaskForSlice(false, uLodLevel);
+		computeBitmaskForSlice<false, uLodLevel>();
 		uNoOfNonEmptyCellsForSlice1 = m_uNoOfOccupiedCells;
 
 		if(uNoOfNonEmptyCellsForSlice1 != 0)
@@ -100,7 +113,7 @@ namespace PolyVox
 		//Process the first slice (previous slice is available)
 		for(uint32_t uSlice = 1; ((uSlice <= region.depth()) && (uSlice + m_v3dRegionOffset.getZ() <= regVolume.getUpperCorner().getZ())); uSlice += m_uStepSize)
 		{	
-			computeBitmaskForSlice(true, uLodLevel);
+			computeBitmaskForSlice<true, uLodLevel>();
 			uNoOfNonEmptyCellsForSlice1 = m_uNoOfOccupiedCells;
 
 			if(uNoOfNonEmptyCellsForSlice1 != 0)
@@ -133,7 +146,8 @@ namespace PolyVox
 		delete[] m_pCurrentVertexIndicesZ;
 	}
 
-	uint32_t SurfaceExtractor::computeBitmaskForSlice(bool isPrevZAvail, uint8_t uLodLevel)
+	template<bool isPrevZAvail, uint8_t uLodLevel>
+	uint32_t SurfaceExtractor::computeBitmaskForSlice(void)
 	{
 		m_uNoOfOccupiedCells = 0;
 
@@ -151,7 +165,7 @@ namespace PolyVox
 		uYRegSpace = uYVolSpace - m_v3dRegionOffset.getY();
 
 		m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
-		computeBitmaskForCell(false, false, isPrevZAvail, uLodLevel);
+		computeBitmaskForCell<false, false, isPrevZAvail, uLodLevel>();
 
 
 		//Process the edge where x is minimal.
@@ -162,7 +176,7 @@ namespace PolyVox
 			uYRegSpace = uYVolSpace - m_v3dRegionOffset.getY();
 
 			m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
-			computeBitmaskForCell(false, true, isPrevZAvail, uLodLevel);
+			computeBitmaskForCell<false, true, isPrevZAvail, uLodLevel>();
 		}
 
 		//Process the edge where y is minimal.
@@ -173,7 +187,7 @@ namespace PolyVox
 			uYRegSpace = uYVolSpace - m_v3dRegionOffset.getY();
 
 			m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
-			computeBitmaskForCell(true, false, isPrevZAvail, uLodLevel);
+			computeBitmaskForCell<true, false, isPrevZAvail, uLodLevel>();
 		}
 
 		//Process all remaining elemnents of the slice. In this case, previous x and y values are always available
@@ -185,14 +199,15 @@ namespace PolyVox
 				uYRegSpace = uYVolSpace - m_v3dRegionOffset.getY();
 
 				m_sampVolume.setPosition(uXVolSpace,uYVolSpace,uZVolSpace);
-				computeBitmaskForCell(true, true, isPrevZAvail, uLodLevel);
+				computeBitmaskForCell<true, true, isPrevZAvail, uLodLevel>();
 			}
 		}
 
 		return m_uNoOfOccupiedCells;
 	}
 
-	void SurfaceExtractor::computeBitmaskForCell(bool isPrevXAvail, bool isPrevYAvail, bool isPrevZAvail, uint8_t uLodLevel)
+	template<bool isPrevXAvail, bool isPrevYAvail, bool isPrevZAvail, uint8_t uLodLevel>
+	void SurfaceExtractor::computeBitmaskForCell(void)
 	{
 		uint8_t iCubeIndex = 0;