More work on Smooth LOD.

examples/SmoothLOD/OpenGLWidget.cpp

@@ -34,6 +34,28 @@ void OpenGLWidget::setSurfaceMeshToRender(const PolyVox::SurfaceMesh<PositionMat
 	m_uEndIndex = vecIndices.size();
 }
 
+void OpenGLWidget::setSurfaceMeshToRenderLowLOD(const PolyVox::SurfaceMesh<PositionMaterialNormal>& surfaceMesh)
+{
+	//Convienient access to the vertices and indices
+	const vector<uint32_t>& vecIndices = surfaceMesh.getIndices();
+	const vector<PositionMaterialNormal>& vecVertices = surfaceMesh.getVertices();
+
+	//Build an OpenGL index buffer
+	glGenBuffers(1, &indexBufferLow);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBufferLow);
+	const GLvoid* pIndices = static_cast<const GLvoid*>(&(vecIndices[0]));		
+	glBufferData(GL_ELEMENT_ARRAY_BUFFER, vecIndices.size() * sizeof(uint32_t), pIndices, GL_STATIC_DRAW);
+
+	//Build an OpenGL vertex buffer
+	glGenBuffers(1, &vertexBufferLow);
+	glBindBuffer(GL_ARRAY_BUFFER, vertexBufferLow);
+	const GLvoid* pVertices = static_cast<const GLvoid*>(&(vecVertices[0]));	
+	glBufferData(GL_ARRAY_BUFFER, vecVertices.size() * sizeof(PositionMaterialNormal), pVertices, GL_STATIC_DRAW);
+
+	m_uBeginIndexLow = 0;
+	m_uEndIndexLow = vecIndices.size();
+}
+
 void OpenGLWidget::initializeGL()
 {
 	//We need GLEW to access recent OpenGL functionality
@@ -125,6 +147,16 @@ void OpenGLWidget::paintGL()
 	glNormalPointer(GL_FLOAT, sizeof(PositionMaterialNormal), (GLvoid*)12);
 
 	glDrawRangeElements(GL_TRIANGLES, m_uBeginIndex, m_uEndIndex-1, m_uEndIndex - m_uBeginIndex, GL_UNSIGNED_INT, 0);
+
+	//Bind the index buffer
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBufferLow);
+
+	//Bind the vertex buffer
+	glBindBuffer(GL_ARRAY_BUFFER, vertexBufferLow);
+	glVertexPointer(3, GL_FLOAT, sizeof(PositionMaterialNormal), 0);
+	glNormalPointer(GL_FLOAT, sizeof(PositionMaterialNormal), (GLvoid*)12);
+
+	glDrawRangeElements(GL_TRIANGLES, m_uBeginIndexLow, m_uEndIndexLow-1, m_uEndIndexLow - m_uBeginIndexLow, GL_UNSIGNED_INT, 0);
 	
 	GLenum errCode = glGetError();
 	if(errCode != GL_NO_ERROR)

examples/SmoothLOD/OpenGLWidget.h

@@ -42,6 +42,7 @@ public:
 
 	//Convert a SrfaceMesh to OpenGL index/vertex buffers
 	void setSurfaceMeshToRender(const PolyVox::SurfaceMesh<PolyVox::PositionMaterialNormal>& surfaceMesh);
+	void setSurfaceMeshToRenderLowLOD(const PolyVox::SurfaceMesh<PolyVox::PositionMaterialNormal>& surfaceMesh);
 
 protected:
 	//Qt OpenGL functions
@@ -53,10 +54,16 @@ private:
 	//Index/vertex buffer data
 	GLuint m_uBeginIndex;
 	GLuint m_uEndIndex;
-	GLuint noOfIndices;
+	//GLuint noOfIndices;
 	GLuint indexBuffer;
 	GLuint vertexBuffer;
 
+	GLuint m_uBeginIndexLow;
+	GLuint m_uEndIndexLow;
+	//GLuint noOfIndicesLow;
+	GLuint indexBufferLow;
+	GLuint vertexBufferLow;
+
 	//Mouse data
 	QPoint m_LastFrameMousePos;
 	QPoint m_CurrentMousePos;

examples/SmoothLOD/main.cpp

@@ -91,20 +91,26 @@ int main(int argc, char *argv[])
 	smoothRegion<SimpleVolume, Density8>(volData, volData.getEnclosingRegion());
 	smoothRegion<SimpleVolume, Density8>(volData, volData.getEnclosingRegion());
 
-	RawVolume<Density8> volDataLowLOD(PolyVox::Region(Vector3DInt32(0,0,0), Vector3DInt32(31, 31, 31)));
+	RawVolume<Density8> volDataLowLOD(PolyVox::Region(Vector3DInt32(0,0,0), Vector3DInt32(15, 31, 31)));
 
-	VolumeResampler<SimpleVolume, RawVolume, Density8> volumeResampler(&volData, volData.getEnclosingRegion(), &volDataLowLOD, volDataLowLOD.getEnclosingRegion());
+	VolumeResampler<SimpleVolume, RawVolume, Density8> volumeResampler(&volData, PolyVox::Region(Vector3DInt32(0,0,0), Vector3DInt32(31, 63, 63)), &volDataLowLOD, volDataLowLOD.getEnclosingRegion());
 	volumeResampler.execute();
 
 	//Extract the surface
-	SurfaceMesh<PositionMaterialNormal> mesh;
+	SurfaceMesh<PositionMaterialNormal> meshLowLOD;
-	SurfaceExtractor<RawVolume, Density8 > surfaceExtractor(&volDataLowLOD, volDataLowLOD.getEnclosingRegion(), &mesh);
+	SurfaceExtractor<RawVolume, Density8 > surfaceExtractor(&volDataLowLOD, volDataLowLOD.getEnclosingRegion(), &meshLowLOD);
 	surfaceExtractor.execute();
+	meshLowLOD.scaleVertices(2.0f);
 
-	mesh.scaleVertices(2.0f);
+	//Extract the surface
+	SurfaceMesh<PositionMaterialNormal> meshHighLOD;
+	SurfaceExtractor<SimpleVolume, Density8 > surfaceExtractorHigh(&volData, PolyVox::Region(Vector3DInt32(32,0,0), Vector3DInt32(63, 63, 63)), &meshHighLOD);
+	surfaceExtractorHigh.execute();
+	meshHighLOD.translateVertices(Vector3DFloat(32, 0, 0));
 
 	//Pass the surface to the OpenGL window
-	openGLWidget.setSurfaceMeshToRender(mesh);
+	openGLWidget.setSurfaceMeshToRender(meshHighLOD);
+	openGLWidget.setSurfaceMeshToRenderLowLOD(meshLowLOD);
 
 	//Run the message pump.
 	return app.exec();

library/PolyVoxCore/include/PolyVoxCore/SurfaceMesh.h

@@ -64,6 +64,7 @@ namespace PolyVox
 	   bool isEmpty(void) const;
 
 	   void scaleVertices(float amount);
+	   void translateVertices(const Vector3DFloat& amount);
 
 	   //THESE FUNCTIONS TO BE REMOVED IN THE FUTURE. OR AT LEAST MOVED OUT OF THIS CLASS INTO FREE FUNCTIONS.
 	   //THEY ARE CAUSING PROBLEMS WITH THE SWIG BINDINGS. THE FUNCTIONS REGARDING NORMALS MAKE NO SENSE WHEN

library/PolyVoxCore/include/PolyVoxCore/SurfaceMesh.inl

@@ -475,4 +475,16 @@ namespace PolyVox
 			m_vecVertices[ct].setPosition(position);
 		}
 	}
+
+	template <typename VertexType>
+	void SurfaceMesh<VertexType>::translateVertices(const Vector3DFloat& amount)
+	{
+		for(uint32_t ct = 0; ct < m_vecVertices.size(); ct++)
+		{
+			//TODO: Should rethink accessors here to provide faster access
+			Vector3DFloat position = m_vecVertices[ct].getPosition();
+			position += amount;
+			m_vecVertices[ct].setPosition(position);
+		}
+	}
 }

library/PolyVoxCore/include/PolyVoxCore/VolumeResampler.h

@@ -39,6 +39,7 @@ namespace PolyVox
 	private:
 		void resampleSameSize();
 		void resampleHalfSize();
+		void resampleArbitrary();
 
 		//Source data
 		SrcVolumeType<VoxelType>* m_pVolSrc;

library/PolyVoxCore/include/PolyVoxCore/VolumeResampler.inl

@@ -35,8 +35,26 @@ namespace PolyVox
 	template< template<typename> class SrcVolumeType, template<typename> class DestVolumeType, typename VoxelType>
 	void VolumeResampler<SrcVolumeType, DestVolumeType, VoxelType>::execute()
 	{
-		//resampleSameSize();
+		int32_t uSrcWidth = m_regSrc.getUpperCorner().getX() - m_regSrc.getLowerCorner().getX() + 1;
-		resampleHalfSize();
+		int32_t uSrcHeight = m_regSrc.getUpperCorner().getY() - m_regSrc.getLowerCorner().getY() + 1;
+		int32_t uSrcDepth = m_regSrc.getUpperCorner().getZ() - m_regSrc.getLowerCorner().getZ() + 1;
+
+		int32_t uDstWidth = m_regDst.getUpperCorner().getX() - m_regDst.getLowerCorner().getX() + 1;
+		int32_t uDstHeight = m_regDst.getUpperCorner().getY() - m_regDst.getLowerCorner().getY() + 1;
+		int32_t uDstDepth = m_regDst.getUpperCorner().getZ() - m_regDst.getLowerCorner().getZ() + 1;
+
+		if((uSrcWidth == uDstWidth) && (uSrcHeight == uDstHeight) && (uSrcDepth == uDstDepth))
+		{
+			resampleSameSize();
+		}
+		else if((uSrcWidth == uDstWidth * 2) && (uSrcHeight == uDstHeight * 2) && (uSrcDepth == uDstDepth * 2))
+		{
+			resampleHalfSize();
+		}
+		else
+		{
+			resampleArbitrary();
+		}
 	}
 
 	template< template<typename> class SrcVolumeType, template<typename> class DestVolumeType, typename VoxelType>
@@ -92,4 +110,11 @@ namespace PolyVox
 			}
 		}
 	}
+
+	template< template<typename> class SrcVolumeType, template<typename> class DestVolumeType, typename VoxelType>
+	void VolumeResampler<SrcVolumeType, DestVolumeType, VoxelType>::resampleArbitrary()
+	{
+		//ARBITRARY RESAMPLING NOT YET IMPLEMENTED.
+		assert(false); 
+	}
 }