bool
PxrUsdKatana_AreRelTargetsFromBaseMaterial(const UsdRelationship &rel)
{
// Find the strongest opinion about the relationship targets.
SdfRelationshipSpecHandle strongestRelSpec;
SdfPropertySpecHandleVector propStack = rel.GetPropertyStack();
for (const SdfPropertySpecHandle &prop: propStack) {
if (SdfRelationshipSpecHandle relSpec =
TfDynamic_cast<SdfRelationshipSpecHandle>(prop)) {
if (relSpec->HasTargetPathList()) {
strongestRelSpec = relSpec;
break;
}
}
}
// Find which prim node introduced that opinion.
if (strongestRelSpec) {
for(const PcpNodeRef &node:
rel.GetPrim().GetPrimIndex().GetNodeRange()) {
if (node.GetPath() == strongestRelSpec->GetPath().GetPrimPath() &&
node.GetLayerStack()->HasLayer(strongestRelSpec->GetLayer())) {
return _NodeRepresentsLiveBaseMaterial(node);
}
}
}
return false;
}
SdfAttributeSpecHandle
SdfAttributeSpec::_New(
const SdfRelationshipSpecHandle& owner,
const SdfPath& path,
const std::string& name,
const SdfValueTypeName& typeName,
SdfVariability variability,
bool custom)
{
if (not owner) {
TF_CODING_ERROR("NULL owner");
return TfNullPtr;
}
if (not typeName) {
TF_CODING_ERROR("Cannot create attribute spec <%s> with invalid type",
owner->GetPath().AppendTarget(path).
AppendProperty(TfToken(name)).GetText());
return TfNullPtr;
}
SdfChangeBlock block;
// Determine the path of the relationship target
SdfPath absPath = path.MakeAbsolutePath(owner->GetPath().GetPrimPath());
SdfPath targetPath = owner->GetPath().AppendTarget(absPath);
// Check to make sure that the name is valid
if (not Sdf_ChildrenUtils<Sdf_AttributeChildPolicy>::IsValidName(name)) {
TF_CODING_ERROR(
"Cannot create attribute on %s with invalid name: %s",
targetPath.GetText(), name.c_str());
return TfNullPtr;
}
// Create the relationship target if it doesn't already exist. Note
// that this does not automatically get added to the relationship's
// target path list.
SdfSpecHandle targetSpec = owner->_FindOrCreateTargetSpec(path);
// AttributeSpecs are considered initially to have only required fields
// only if they are not custom.
bool hasOnlyRequiredFields = (not custom);
// Create the relational attribute spec
SdfPath attrPath = targetPath.AppendRelationalAttribute(TfToken(name));
if (not Sdf_ChildrenUtils<Sdf_AttributeChildPolicy>::CreateSpec(
owner->GetLayer(), attrPath, SdfSpecTypeAttribute,
hasOnlyRequiredFields)) {
return TfNullPtr;
}
SdfAttributeSpecHandle spec =
owner->GetLayer()->GetAttributeAtPath(attrPath);
// Avoid expensive dormancy checks in the case of binary-backed data.
SdfAttributeSpec *specPtr = get_pointer(spec);
if (TF_VERIFY(specPtr)) {
specPtr->SetField(SdfFieldKeys->Custom, custom);
specPtr->SetField(SdfFieldKeys->TypeName, typeName.GetAsToken());
specPtr->SetField(SdfFieldKeys->Variability, variability);
}
return spec;
}