bool CSGSlicer::slice( const Cell& cell, const MeshSlicerInfo& info, MFnMesh& outMesh ) {
// copy maya mesh to csg.js model
csgjs_model jsModel;
MItMeshVertex it(_sourceMesh);
while( !it.isDone() ) {
csgjs_vertex vtx;
// get position
MPoint pos = it.position(MSpace::kWorld);
vtx.pos = csgjs_vector(static_cast<float>(pos.x), static_cast<float>(pos.y), static_cast<float>(pos.z));
// add position
jsModel.vertices.push_back(vtx);
it.next();
}
MIntArray triangleCounts;
MIntArray triangleVertices;
MFnMesh(_sourceMesh).getTriangles(triangleCounts, triangleVertices);
for( unsigned int i = 0; i < triangleVertices.length(); ++i ) {
jsModel.indices.push_back(triangleVertices[i]);
}
// convert cell into csgjs_model
csgjs_model cellModel;
int indexOffset = 0;
const auto& planePoints = cell.getPlanePoints();
for( const auto& points : planePoints ) {
for( const auto& pnt : points ) {
csgjs_vertex vtx;
vtx.pos = csgjs_vector(pnt.x, pnt.y, pnt.z);
cellModel.vertices.push_back(vtx);
}
const auto& indices = HadanConvexTriangulate(points);
for( const auto& idx : indices ) {
cellModel.indices.push_back(indexOffset + idx[0]);
cellModel.indices.push_back(indexOffset + idx[1]);
cellModel.indices.push_back(indexOffset + idx[2]);
}
indexOffset += static_cast<int>(points.size());
}
// perform intersection
const csgjs_model result = csgjs_intersection(jsModel, cellModel);
// copy back to maya mesh
MPointArray pointArray;
for( const auto& vtx : result.vertices ) {
pointArray.append(MPoint(vtx.pos.x, vtx.pos.y, vtx.pos.z));
}
MIntArray faceConnects;
for( const auto& idx : result.indices ) {
faceConnects.append(idx);
}
MIntArray faceCounts;
for( size_t i = 0; i < result.indices.size() / 3; ++i ) {
faceCounts.append(3);
}
{
std::unique_lock<std::mutex> lock(CSGJS_CREATEMESH_MUTEX);
outMesh.create(pointArray.length(), faceCounts.length(), pointArray, faceCounts, faceConnects);
}
return true;
}
inline static csgjs_vector cross(const csgjs_vector & a, const csgjs_vector & b) { return csgjs_vector(a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x); }
inline static csgjs_vector operator - (const csgjs_vector & a, const csgjs_vector & b) { return csgjs_vector(a.x - b.x, a.y - b.y, a.z - b.z); }
inline static csgjs_vector operator * (const csgjs_vector & a, float b) { return csgjs_vector(a.x * b, a.y * b, a.z * b); }
inline static csgjs_vector operator + (const csgjs_vector & a, const csgjs_vector & b) { return csgjs_vector(a.x + b.x, a.y + b.y, a.z + b.z); }
