void geometryReplicatorGeometryOverride::populateGeometry(
const MGeometryRequirements& requirements,
const MRenderItemList& renderItems,
MGeometry& data)
{
if (!fPath.isValid())
return;
// MGeometryExtractor::MGeometryExtractor.
// here, fPath is the path of the linked object instead of the plugin node; it
// is used to determine the right type of the geometry shape, e.g., polygon
// or NURBS surface.
// The sharing flag (true here) is just for the polygon shape.
MStatus status;
MPolyGeomOptions options = kPolyGeom_Normal;
if( isBaseMesh() ) options = options|kPolyGeom_BaseMesh;
MGeometryExtractor extractor(requirements, fPath, options, &status);
if (MS::kFailure == status)
return;
// fill vertex buffer
const MVertexBufferDescriptorList& descList = requirements.vertexRequirements();
for (int reqNum = 0; reqNum < descList.length(); ++reqNum)
{
MVertexBufferDescriptor desc;
if (!descList.getDescriptor(reqNum, desc))
{
continue;
}
switch (desc.semantic())
{
case MGeometry::kPosition:
case MGeometry::kNormal:
case MGeometry::kTexture:
case MGeometry::kTangent:
case MGeometry::kBitangent:
case MGeometry::kColor:
{
MVertexBuffer* vertexBuffer = data.createVertexBuffer(desc);
if (vertexBuffer) {
// MGeometryExtractor::vertexCount and MGeometryExtractor::populateVertexBuffer.
// since the plugin node has the same vertex data as its linked scene object,
// call vertexCount to allocate vertex buffer of the same size, and then call
// populateVertexBuffer to copy the data.
unsigned int vertexCount = extractor.vertexCount();
float* data = (float*)vertexBuffer->acquire(vertexCount, true /*writeOnly - we don't need the current buffer values*/);
if (data) {
status = extractor.populateVertexBuffer(data, vertexCount, desc);
if (MS::kFailure == status)
return;
vertexBuffer->commit(data);
}
}
}
break;
default:
// do nothing for stuff we don't understand
break;
}
}
// fill index buffer
for (int i = 0; i < renderItems.length(); ++i)
{
const MRenderItem* item = renderItems.itemAt(i);
if (!item) continue;
MIndexBuffer* indexBuffer = data.createIndexBuffer(MGeometry::kUnsignedInt32);
if (!indexBuffer) continue;
// MGeometryExtractor::primitiveCount and MGeometryExtractor::populateIndexBuffer.
// since the plugin node has the same index data as its linked scene object,
// call primitiveCount to allocate index buffer of the same size, and then call
// populateIndexBuffer to copy the data.
if (item->primitive() == MGeometry::kTriangles)
{
MIndexBufferDescriptor triangleDesc(MIndexBufferDescriptor::kTriangle, MString(), MGeometry::kTriangles, 3);
unsigned int numTriangles = extractor.primitiveCount(triangleDesc);
unsigned int* indices = (unsigned int*)indexBuffer->acquire(3 * numTriangles, true /*writeOnly - we don't need the current buffer values*/);
status = extractor.populateIndexBuffer(indices, numTriangles, triangleDesc);
if (MS::kFailure == status)
return;
indexBuffer->commit(indices);
}
else if (item->primitive() == MGeometry::kLines)
{
MIndexBufferDescriptor edgeDesc(MIndexBufferDescriptor::kEdgeLine, MString(), MGeometry::kLines, 2);
unsigned int numEdges = extractor.primitiveCount(edgeDesc);
unsigned int* indices = (unsigned int*)indexBuffer->acquire(2 * numEdges, true /*writeOnly - we don't need the current buffer values*/);
status = extractor.populateIndexBuffer(indices, numEdges, edgeDesc);
if (MS::kFailure == status)
return;
indexBuffer->commit(indices);
}
item->associateWithIndexBuffer(indexBuffer);
}
}
