// Given an Op, value and time, set the Op value based on op type and precision
static void
setXformOp(const UsdGeomXformOp& op,
const GfVec3d& value,
const UsdTimeCode& usdTime)
{
if (op.GetOpType() == UsdGeomXformOp::TypeTransform) {
GfMatrix4d shearXForm(1.0);
shearXForm[1][0] = value[0]; //xyVal
shearXForm[2][0] = value[1]; //xzVal
shearXForm[2][1] = value[2]; //yzVal
op.Set(shearXForm, usdTime);
return;
}
if (UsdGeomXformOp::GetPrecisionFromValueTypeName(op.GetAttr().GetTypeName())
== UsdGeomXformOp::PrecisionDouble) {
_setXformOp<GfVec3d>(op, value, usdTime);
}
else { // float precision
_setXformOp<GfVec3f>(op, GfVec3f(value), usdTime);
}
}
bool
PxrUsdTranslators_InstancerWriter::writeInstancerAttrs(
const UsdTimeCode& usdTime,
const UsdGeomPointInstancer& instancer)
{
MStatus status = MS::kSuccess;
MFnDagNode dagNode(GetDagPath(), &status);
CHECK_MSTATUS_AND_RETURN(status, false);
// Note: In this function, we don't read instances using the provided
// MFnInstancer API. One reason is that it breaks up prototypes into their
// constituent shapes, and there's no way to figure out which hierarchy
// they came from. Another reason is that it only provides computed matrices
// and not separate position, rotation, scale attrs.
const SdfPath prototypesGroupPath =
instancer.GetPrim().GetPath().AppendChild(_tokens->Prototypes);
// At the default time, setup all the prototype instances.
if (usdTime.IsDefault()) {
const MPlug inputHierarchy = dagNode.findPlug("inputHierarchy", true,
&status);
CHECK_MSTATUS_AND_RETURN(status, false);
// Note that the "Prototypes" prim needs to be a model group to ensure
// contiguous model hierarchy.
const UsdPrim prototypesGroupPrim = GetUsdStage()->DefinePrim(
prototypesGroupPath);
UsdModelAPI(prototypesGroupPrim).SetKind(KindTokens->group);
_modelPaths.push_back(prototypesGroupPath);
UsdRelationship prototypesRel = instancer.CreatePrototypesRel();
const unsigned int numElements = inputHierarchy.numElements();
for (unsigned int i = 0; i < numElements; ++i) {
const MPlug plug = inputHierarchy[i];
const MPlug source(UsdMayaUtil::GetConnected(plug));
if (source.isNull()) {
TF_WARN("Cannot read prototype: the source plug %s was null",
plug.name().asChar());
return false;
}
MFnDagNode sourceNode(source.node(), &status);
CHECK_MSTATUS_AND_RETURN(status, false);
MDagPath prototypeDagPath;
sourceNode.getPath(prototypeDagPath);
// Prototype names are guaranteed unique by virtue of having a
// unique numerical suffix _# indicating the prototype index.
const TfToken prototypeName(
TfStringPrintf("%s_%d", sourceNode.name().asChar(), i));
const SdfPath prototypeUsdPath = prototypesGroupPrim.GetPath()
.AppendChild(prototypeName);
UsdPrim prototypePrim = GetUsdStage()->DefinePrim(
prototypeUsdPath);
_modelPaths.push_back(prototypeUsdPath);
// Try to be conservative and only create an intermediary xformOp
// with the instancerTranslate if we can ensure that we don't need
// to compensate for the translation on the prototype root.
//
// XXX: instancerTranslate does not behave well when added to a
// reference that has an existing transform on the far side of the
// reference. However, its behavior at least matches the
// behavior in UsdMayaTranslatorModelAssembly. If we fix the
// behavior there, we need to make sure that this is also
// fixed to match.
bool instancerTranslateAnimated = false;
if (_NeedsExtraInstancerTranslate(
prototypeDagPath, &instancerTranslateAnimated)) {
UsdGeomXformable xformable(prototypePrim);
UsdGeomXformOp newOp = xformable.AddTranslateOp(
UsdGeomXformOp::PrecisionDouble,
_tokens->instancerTranslate);
_instancerTranslateOps.push_back(
{prototypeDagPath, newOp, instancerTranslateAnimated});
}
// Two notes:
// (1) We don't un-instance here, because it's OK for the prototype
// to just be a reference to an instance master if the prototype
// participates in Maya native instancing.
// (2) The prototype root must be visible to match Maya's behavior,
// which always vis'es the prototype root, even if it is marked
// hidden.
_writeJobCtx.CreatePrimWriterHierarchy(
prototypeDagPath,
prototypeUsdPath,
/*forceUninstance*/ false,
/*exportRootVisibility*/ false,
&_prototypeWriters);
prototypesRel.AddTarget(prototypeUsdPath);
}
_numPrototypes = numElements;
}
// If there aren't any prototypes, fail and don't export on subsequent
// time-sampled exports.
if (_numPrototypes == 0) {
return false;
}
// Actual write of prototypes (@ both default time and animated time).
for (UsdMayaPrimWriterSharedPtr& writer : _prototypeWriters) {
writer->Write(usdTime);
if (usdTime.IsDefault()) {
// Prototype roots should have kind component or derived.
// Calling Write() above may have populated kinds, so don't stomp
// over existing component-derived kinds.
// (Note that ModelKindWriter's fix-up stage might change this.)
if (writer->GetUsdPath().GetParentPath() == prototypesGroupPath) {
if (const UsdPrim writerPrim = writer->GetUsdPrim()) {
UsdModelAPI primModelAPI(writerPrim);
TfToken kind;
primModelAPI.GetKind(&kind);
if (!KindRegistry::IsA(kind, KindTokens->component)) {
primModelAPI.SetKind(KindTokens->component);
}
}
}
}
}
// Write the instancerTranslate xformOp for all prims that need it.
// (This should happen @ default time or animated time depending on whether
// the xform is animated.)
for (const _TranslateOpData& opData : _instancerTranslateOps) {
if (opData.isAnimated != usdTime.IsDefault()) {
GfVec3d origin;
if (_GetTransformedOriginInLocalSpace(opData.mayaPath, &origin)) {
UsdGeomXformOp translateOp = opData.op;
_SetAttribute(translateOp.GetAttr(), -origin, usdTime);
}
}
}
// Grab the inputPoints data from the source plug.
// (This attribute's value must come from a source plug; it isn't
// directly writeable. Thus reading it directly may not give the right
// value depending on Maya's execution behavior.)
MPlug inputPointsDest = dagNode.findPlug("inputPoints", true, &status);
CHECK_MSTATUS_AND_RETURN(status, false);
MPlug inputPointsSrc = UsdMayaUtil::GetConnected(inputPointsDest);
if (inputPointsSrc.isNull()) {
TF_WARN("inputPoints not connected on instancer '%s'",
GetDagPath().fullPathName().asChar());
return false;
}
auto holder = UsdMayaUtil::GetPlugDataHandle(inputPointsSrc);
if (!holder) {
TF_WARN("Unable to read inputPoints data handle for instancer '%s'",
GetDagPath().fullPathName().asChar());
return false;
}
MFnArrayAttrsData inputPointsData(holder->GetDataHandle().data(),
&status);
CHECK_MSTATUS_AND_RETURN(status, false);
if (!UsdMayaWriteUtil::WriteArrayAttrsToInstancer(
inputPointsData, instancer, _numPrototypes, usdTime,
_GetSparseValueWriter())) {
return false;
}
// Load the completed point instancer to compute and set its extent.
instancer.GetPrim().GetStage()->Load(instancer.GetPath());
VtArray<GfVec3f> extent(2);
if (instancer.ComputeExtentAtTime(&extent, usdTime, usdTime)) {
_SetAttribute(instancer.CreateExtentAttr(), &extent, usdTime);
}
return true;
}