customPrimitiveGenerator/customPrimitiveGenerator.cpp

customPrimitiveGenerator/customPrimitiveGenerator.cpp
//-
// ==========================================================================
// Copyright 2012 Autodesk, Inc. All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk
// license agreement provided at the time of installation or download,
// or which otherwise accompanies this software in either electronic
// or hard copy form.
// ==========================================================================
//+
// Example plugin: customPrimitiveGenerator.cpp
//
// This plug-in is an example of a custom MPxPrimitiveGenerator.
// It provides custom primitives based on shader requirements coming from
// an MPxShaderOverride. The name() in the MIndexBufferDescriptor is used
// to signify a unique identifier for a custom buffer.
// This primitive generator is provided for demonstration purposes only.
// It simply provides a triangle list for mesh objects with no vertex sharing.
// A more sophisticated primitive provider could be used to provide patch primitives
// for GPU tessellation.
// This plugin is meant to be used in conjunction with the dx11Shader, cgfxShader, glslShader or the hwPhongShader plugins.
// The customPrimitiveGeneratorDX11.fx (dx11Shader), customPrimitiveGeneratorGL.cgfx (cgfxShader)
// and customPrimitiveGenerator.osgfx (glslShader) files accompanying this sample
// can be loaded using the appropriate shader plugin.
// In any case, the environment variable MAYA_USE_CUSTOMPRIMITIVEGENERATOR needs to be set (any value is fine) for it to be enabled.
#include <maya/MStatus.h>
#include <maya/MFnMesh.h>
#include <maya/MIntArray.h>
#include <maya/MFloatVectorArray.h>
#include <maya/MPxPrimitiveGenerator.h>
#include <maya/MPxVertexBufferGenerator.h>
#include <maya/MHWGeometry.h>
#include <maya/MDrawRegistry.h>
#include <maya/MApiVersion.h>
#include <list>
using namespace MHWRender;
class MyCustomPrimitiveGenerator : public MPxPrimitiveGenerator
{
public:
MyCustomPrimitiveGenerator() {}
virtual ~MyCustomPrimitiveGenerator() {}
virtual unsigned int computeIndexCount(const MObject& object, const MObject& component) const
{
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return 0; // failed
return mesh.numFaceVertices();
}
virtual MGeometry::Primitive generateIndexing(const MObject& object, const MObject& component,
const MComponentDataIndexingList& /*sourceIndexing*/,
const MComponentDataIndexingList& targetIndexing,
MIndexBuffer& indexBuffer,
int& primitiveStride) const
{
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return MGeometry::kInvalidPrimitive; // failed
for (int x = 0; x < targetIndexing.length(); ++x)
{
const MComponentDataIndexing* target = targetIndexing[x];
if (target->componentType() == MComponentDataIndexing::kFaceVertex)
{
// Get Triangles
MIntArray triCounts;
MIntArray triVertIDs;
mesh.getTriangleOffsets(triCounts, triVertIDs);
unsigned int numTriVerts = triVertIDs.length();
unsigned int customNumTriVerts = numTriVerts * 2;
void* indexData = indexBuffer.acquire(customNumTriVerts, true /*writeOnly - we don't need the current buffer values*/);
if (indexData == NULL)
const MUintArray& sharedIndices = target->indices();
// Crawl the sharedIndices array to find the last
// The new vertices will be added at the end
unsigned int nextNewVertexIndex = 0;
for(unsigned int idx = 0; idx < sharedIndices.length(); ++idx)
nextNewVertexIndex = std::max(nextNewVertexIndex, sharedIndices[idx]);
++nextNewVertexIndex;
unsigned int newTriId = 0;
for(unsigned int triId = 0; triId < numTriVerts; )
{
// split each triangle in two : add new vertex between vertexId1 and vertexId2
unsigned int vertexId0 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId1 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId2 = sharedIndices[triVertIDs[triId++]];
unsigned int newVertexIndex = nextNewVertexIndex++;
// Triangle 0 1 2 become two triangles : 0 1 X and 0 X 2
if (indexBuffer.dataType() == MGeometry::kUnsignedInt32) {
((unsigned int*)indexData)[newTriId++] = vertexId0;
((unsigned int*)indexData)[newTriId++] = vertexId1;
((unsigned int*)indexData)[newTriId++] = newVertexIndex;
((unsigned int*)indexData)[newTriId++] = vertexId0;
((unsigned int*)indexData)[newTriId++] = newVertexIndex;
((unsigned int*)indexData)[newTriId++] = vertexId2;
}
else if (indexBuffer.dataType() == MGeometry::kUnsignedChar) {
((unsigned short*)indexData)[newTriId++] = (unsigned short)vertexId0;
((unsigned short*)indexData)[newTriId++] = (unsigned short)vertexId1;
((unsigned short*)indexData)[newTriId++] = (unsigned short)newVertexIndex;
((unsigned short*)indexData)[newTriId++] = (unsigned short)vertexId0;
((unsigned short*)indexData)[newTriId++] = (unsigned short)newVertexIndex;
((unsigned short*)indexData)[newTriId++] = (unsigned short)vertexId2;
}
}
indexBuffer.commit(indexData);
primitiveStride = 3;
}
}
}
};
// This is the primitive generator creation function registered with the DrawRegistry.
// Used to initialize a custom primitive generator.
static MPxPrimitiveGenerator* createMyCustomPrimitiveGenerator()
{
return new MyCustomPrimitiveGenerator();
}
class MyCustomPositionBufferGenerator : public MPxVertexBufferGenerator
{
public:
MyCustomPositionBufferGenerator() {}
virtual ~MyCustomPositionBufferGenerator() {}
virtual bool getSourceIndexing(const MObject& object,
MComponentDataIndexing& sourceIndexing) const
{
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return false; // failed
MIntArray vertexCount, vertexList;
mesh.getVertices(vertexCount, vertexList);
unsigned int vertCount = vertexList.length();
MUintArray& vertices = sourceIndexing.indices();
vertices.setLength(vertCount);
for(unsigned int i = 0; i < vertCount; ++i)
vertices[i] = (unsigned int)vertexList[i];
// assign the source indexing
sourceIndexing.setComponentType(MComponentDataIndexing::kFaceVertex);
return true;
}
virtual bool getSourceStreams(const MObject& object,
MStringArray &sourceStreams) const
{
// No source stream needed
return false;
}
virtual void createVertexStream(const MObject& object,
MVertexBuffer& vertexBuffer, const MComponentDataIndexing& targetIndexing, const MComponentDataIndexing& sharedIndexing, const MVertexBufferArray& /*sourceStreams*/) const
{
// get the descriptor from the vertex buffer.
// It describes the format and layout of the stream.
const MVertexBufferDescriptor& descriptor = vertexBuffer.descriptor();
// we are expecting a float stream.
MGeometry::DataType dataType = descriptor.dataType();
if (dataType != MGeometry::kFloat)
return;
// we are expecting a dimension of 3
int dimension = descriptor.dimension();
if (dimension != 3)
return;
// we are expecting a position channel
if (descriptor.semantic() != MGeometry::kPosition)
return;
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return; // failed
const MUintArray& indices = targetIndexing.indices();
unsigned int vertexCount = indices.length();
if (vertexCount <= 0)
return;
// Keep track of the vertices that will be used to created a new vertex in-between
typedef std::list< std::pair< unsigned int, unsigned int > > ExtraVerticesList;
ExtraVerticesList extraVertices;
{
// Get Triangles
MIntArray triCounts;
MIntArray triVertIDs;
mesh.getTriangleOffsets(triCounts, triVertIDs);
unsigned int numTriVerts = triVertIDs.length();
const MUintArray& sharedIndices = sharedIndexing.indices();
for(unsigned int triId = 0; triId < numTriVerts; )
{
// split each triangle in two : add new vertex between vertexId1 and vertexId2
triId++; //unsigned int vertexId0 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId1 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId2 = sharedIndices[triVertIDs[triId++]];
extraVertices.push_back( std::make_pair(vertexId1, vertexId2) );
}
}
unsigned int newVertexCount = vertexCount + (unsigned int)extraVertices.size();
float* customBuffer = (float*)vertexBuffer.acquire(newVertexCount, true /*writeOnly - we don't need the current buffer values*/);
if(customBuffer)
{
float* customBufferStart = customBuffer;
// Append 'real' vertices position
unsigned int vertId = 0;
for(; vertId < vertexCount; ++vertId)
{
unsigned int vertexId = indices[vertId];
MPoint point;
mesh.getPoint(vertexId, point);
customBuffer[vertId * dimension] = (float)point.x;
customBuffer[vertId * dimension + 1] = (float)point.y;
customBuffer[vertId * dimension + 2] = (float)point.z;
}
// Append the new vertices position, interpolated from vert1 and vert2
ExtraVerticesList::const_iterator it = extraVertices.begin();
ExtraVerticesList::const_iterator itEnd = extraVertices.end();
for(; it != itEnd; ++it, ++vertId)
{
unsigned int vertexId1 = indices[it->first];
unsigned int vertexId2 = indices[it->second];
MPoint point1, point2;
mesh.getPoint(vertexId1, point1);
mesh.getPoint(vertexId2, point2);
MPoint point = (point1 + point2) / 2.0f;
customBuffer[vertId * dimension] = (float)point.x;
customBuffer[vertId * dimension + 1] = (float)point.y;
customBuffer[vertId * dimension + 2] = (float)point.z;
}
vertexBuffer.commit(customBufferStart);
}
}
};
// This is the buffer generator creation function registered with the DrawRegistry.
// Used to initialize the generator.
static MPxVertexBufferGenerator* createMyCustomPositionBufferGenerator()
{
return new MyCustomPositionBufferGenerator();
}
class MyCustomNormalBufferGenerator : public MPxVertexBufferGenerator
{
public:
MyCustomNormalBufferGenerator() {}
virtual ~MyCustomNormalBufferGenerator() {}
virtual bool getSourceIndexing(const MObject& object,
MComponentDataIndexing& sourceIndexing) const
{
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return false; // failed
MIntArray vertexCount, vertexList;
mesh.getVertices(vertexCount, vertexList);
unsigned int vertCount = vertexList.length();
MUintArray& vertices = sourceIndexing.indices();
vertices.setLength(vertCount);
for(unsigned int i = 0; i < vertCount; ++i)
vertices[i] = (unsigned int)vertexList[i];
// assign the source indexing
sourceIndexing.setComponentType(MComponentDataIndexing::kFaceVertex);
return true;
}
virtual bool getSourceStreams(const MObject& object,
MStringArray &sourceStreams) const
{
// No source stream needed
return false;
}
virtual void createVertexStream(const MObject& object,
MVertexBuffer& vertexBuffer, const MComponentDataIndexing& targetIndexing, const MComponentDataIndexing& sharedIndexing, const MVertexBufferArray& /*sourceStreams*/) const
{
// get the descriptor from the vertex buffer.
// It describes the format and layout of the stream.
const MVertexBufferDescriptor& descriptor = vertexBuffer.descriptor();
// we are expecting a float stream.
MGeometry::DataType dataType = descriptor.dataType();
if (dataType != MGeometry::kFloat)
return;
// we are expecting a dimension of 3
int dimension = descriptor.dimension();
if (dimension != 3)
return;
// we are expecting a normal channel
if (descriptor.semantic() != MGeometry::kNormal)
return;
// get the mesh from the current path
// if it is not a mesh we do nothing.
MStatus status;
MFnMesh mesh(object, &status);
if (!status) return; // failed
const MUintArray& indices = targetIndexing.indices();
unsigned int vertexCount = indices.length();
if (vertexCount <= 0)
return;
// Keep track of the vertices that will be used to created a new vertex in-between
typedef std::list< std::pair< unsigned int, unsigned int > > ExtraVerticesList;
ExtraVerticesList extraVertices;
{
// Get Triangles
MIntArray triCounts;
MIntArray triVertIDs;
mesh.getTriangleOffsets(triCounts, triVertIDs);
unsigned int numTriVerts = triVertIDs.length();
const MUintArray& sharedIndices = sharedIndexing.indices();
for(unsigned int triId = 0; triId < numTriVerts;)
{
// split each triangle in two : add new vertex between vertexId1 and vertexId2
triId++; //unsigned int vertexId0 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId1 = sharedIndices[triVertIDs[triId++]];
unsigned int vertexId2 = sharedIndices[triVertIDs[triId++]];
extraVertices.push_back( std::make_pair(vertexId1, vertexId2) );
}
}
unsigned int newVertexCount = vertexCount + (unsigned int)extraVertices.size();
float* customBuffer = (float*)vertexBuffer.acquire(newVertexCount, true /*writeOnly - we don't need the current buffer values*/);
if(customBuffer)
{
float* customBufferStart = customBuffer;
mesh.getNormals(normals);
// Append 'real' vertices normal
unsigned int vertId = 0;
for(; vertId < vertexCount; ++vertId)
{
const MFloatVector& normal = normals[vertId];
customBuffer[vertId * dimension] = normal.x;
customBuffer[vertId * dimension + 1] = normal.y;
customBuffer[vertId * dimension + 2] = normal.z;
}
// Append the new vertices normal, interpolated from vert1 and vert2
ExtraVerticesList::const_iterator it = extraVertices.begin();
ExtraVerticesList::const_iterator itEnd = extraVertices.end();
for(; it != itEnd; ++it, ++vertId)
{
unsigned int vertexId1 = it->first;
unsigned int vertexId2 = it->second;
const MFloatVector& normal1 = normals[vertexId1];
const MFloatVector& normal2 = normals[vertexId2];
MFloatVector normal = (normal1 + normal2) / 2.0f;
customBuffer[vertId * dimension] = normal.x;
customBuffer[vertId * dimension + 1] = normal.y;
customBuffer[vertId * dimension + 2] = normal.z;
}
vertexBuffer.commit(customBufferStart);
}
}
};
// This is the buffer generator creation function registered with the DrawRegistry.
// Used to initialize the generator.
static MPxVertexBufferGenerator* createMyCustomNormalBufferGenerator()
{
return new MyCustomNormalBufferGenerator();
}
// The following routines are used to register/unregister
// the vertex mutators with Maya
//
MStatus initializePlugin( MObject obj )
{
MDrawRegistry::registerPrimitiveGenerator("customPrimitiveTest", createMyCustomPrimitiveGenerator);
MDrawRegistry::registerVertexBufferGenerator("customPositionStream", createMyCustomPositionBufferGenerator);
MDrawRegistry::registerVertexBufferGenerator("customNormalStream", createMyCustomNormalBufferGenerator);
return MS::kSuccess;
}
MStatus uninitializePlugin( MObject obj)
{
return MS::kSuccess;
}