MpxNode compute not firing

[trevor-van-hoof--2]

I've been trying to convert a python test to a C++ node for speed, I'm not very advanced in C++ but I did have success writing MPxNodes before...

So I inherited an MPxNode, gave it 2 input mesh and 1 output mesh attrs (using an instance of MFnTypedAttribute's create).
I steppd through my init function and all operations succeed but the compute never triggers a breakpoint even after connecting both inputs, then the output, disconnecting the output & reconnecting the output, to visible mesh nodes.

So here's my code and any tips to try are appreciated...

Header:

#ifndef NORMALWRAPNODE
#define NORMALWRAPNODE
 
 
#include "main.h"
 
 
class NormalWrap : public MPxNode
{
public:
    NormalWrap(){ }
    virtual ~NormalWrap(){ }
    static void* creator(){ return new NormalWrap; }
    virtual MStatus compute( MPlug&, MDataBlock& );
    static MStatus initialize();
 
    static MString nodeName;
    static MTypeId typeId;
 
protected:
    void projectMesh( MObject&, MObject&, MObject& );
 
    static MObject inMesh;
    static MObject colMesh;
    static MObject outMesh;
};
 
 
#endif

Source:

#include "NormalWrapNode.h"
#include <maya/MIOStream.h>
 
 
MString NormalWrap::nodeName = MString("normalWrap");
MTypeId NormalWrap::typeId = MTypeId(0x8700B);
MObject NormalWrap::inMesh = MObject();
MObject NormalWrap::outMesh = MObject();
MObject NormalWrap::colMesh = MObject();
 
 
MStatus NormalWrap::initialize()
{
	MStatus stat;
	MFnTypedAttribute typedAttr;
 
	inMesh = typedAttr.create("inMesh", "in", MFnData::kMesh, &stat);
	colMesh = typedAttr.create("collisionMesh", "col", MFnData::kMesh, &stat);
	outMesh = typedAttr.create("outMesh", "iout", MFnData::kMesh, &stat);
 
	stat = addAttribute(inMesh);
	stat = addAttribute(colMesh);
	stat = addAttribute(outMesh);
 
	stat = attributeAffects(inMesh, outMesh);
	stat = attributeAffects(colMesh, outMesh);
 
	return stat;
}
 
 
MStatus NormalWrap::compute(MPlug& plug, MDataBlock& data)
{
	if( plug.attribute() != outMesh )
	{
		return MS::kUnknownParameter;
	}
	//validate & grab inputs
	MDataHandle inData = data.inputValue(inMesh);
	MDataHandle colData = data.inputValue(colMesh);
	if( inData.type() != MFnData::kMesh || colData.type() != MFnData::kMesh )
	{
		return MS::kInvalidParameter;
	}
 
	//prep incoming data
	MObject inObj = inData.asMeshTransformed();
	MObject colObj = inData.asMeshTransformed();
 
	//get writable object
	MObject outData = MFnMeshData().create();
 
	//apply functionality
	projectMesh(inObj, colObj, outData);
 
	//push into out channel
	MDataHandle outHandle = data.outputValue(outMesh);
	outHandle.setMObject(outData);
	data.setClean(plug);
 
	return MS::kSuccess;
}
 
 
void NormalWrap::projectMesh( MObject& inMesh, MObject& inCollider, MObject& outObject )
{
	MFnMesh mesh( inMesh );
	MFnMesh collider( inCollider );
 
	MPointArray points = MPointArray();
	mesh.getPoints( points, MSpace::kWorld );
 
	MVector normal ;
	MPointArray outPoints;
 
	MPoint closest;
	bool pointFound;
	for( unsigned int i = 0 ; i < points.length() ; ++i )
	{
		mesh.getVertexNormal(i, normal, MSpace::kWorld);
 
		pointFound = false;
 
		if( collider.intersect( points[i], normal, outPoints, 0.0001, MSpace::kWorld ) )
		{
			closest = outPoints[0];
			pointFound = true;
		}
 
		if( collider.intersect( points[i], -normal, outPoints, 0.0001, MSpace::kWorld ) )
		{
			if( !pointFound || points[i].distanceTo(closest) > points[i].distanceTo(outPoints[0]) )
			{
				closest = outPoints[0];
				pointFound = true;
			}
		}
 
		if( pointFound )
		{
			points.set( closest, i );
		}
	}
 
	mesh.setPoints( points, MSpace::kWorld );
	mesh.copy( inMesh, outObject );
}

[trevor-van-hoof--2]

hehe, compute takes a const MPlug& so I overloaded the method instead of overridden it....
kthxbye

[joe-leveson]

Hello Trevor,

I'm trying to get into the api myself but am vbery new to it. I've compiled and create  the node fine but am struggling to work out the connectiions in Maya. Could you give me instructions for how to do so please?

Many thanks,