HYDRA-718 : Fix added prims being at the wrong place when saving/loading a scene.

lib/flowViewport/API/interfacesImp/fvpDataProducerSceneIndexInterfaceImp.cpp

@@ -58,12 +58,12 @@ bool DataProducerSceneIndexInterfaceImp::addDataProducerSceneIndex(const PXR_NS:
                                                                    const std::string& rendererNames /*= allRenderers*/,
                                                                    const PXR_NS::SdfPath& customDataProducerSceneIndexRootPathForInsertion /*= PXR_NS::SdfPath::AbsoluteRootPath()*/)
 {   
-    //hydraViewportId can DataProducerSceneIndexInterface::allViewports, meaning the user wants customDataProducerSceneIndex to be applied in all viewports.
     PXR_NS::FVP_NS_DEF::DataProducerSceneIndexDataBaseRefPtr dataProducerSceneIndexData  = 
         _CreateDataProducerSceneIndexData(customDataProducerSceneIndex, rendererNames, customDataProducerSceneIndexRootPathForInsertion, dccNode);
     if (nullptr == dataProducerSceneIndexData){
         return false;
     }
+    //PXR_NS::FvpViewportAPITokens->allViewports == hydraViewportId means the user wants customDataProducerSceneIndex to be applied in all viewports.
     if (PXR_NS::FvpViewportAPITokens->allViewports == hydraViewportId){
         //Apply this data producer scene index to all viewports
         return _AddDataProducerSceneIndexToAllViewports(dataProducerSceneIndexData);

lib/flowViewport/API/perViewportSceneIndicesData/fvpDataProducerSceneIndexDataBase.cpp

@@ -164,10 +164,8 @@ void DataProducerSceneIndexDataBase::_CreateSceneIndexChainForDataProducerSceneI
     AddParentPrimToSceneIndex();
 
     //Create a filtering scene index to update the information (transform, visibility,...) from the parent prim.
-    _parentDataModifierSceneIndex = ParentDataModifierSceneIndex::New(_retainedSceneIndex);
-    _parentDataModifierSceneIndex->SetParentPath(_parentPath);//Set the parent path inside
-    _parentDataModifierSceneIndex->SetParentTransformMatrix(_parentMatrix);
-
+    _parentDataModifierSceneIndex = ParentDataModifierSceneIndex::New(_retainedSceneIndex, _parentPath, _parentMatrix, true);
+
     //Add a prefixing scene index to _dataProducerSceneIndex to set the parent which we added to the retainedsceneindex
     HdPrefixingSceneIndexRefPtr prefixingSceneIndex = HdPrefixingSceneIndex::New(_dataProducerSceneIndex, _parentPath);
 

lib/flowViewport/API/samples/fvpDataProducerSceneIndexExample.cpp

@@ -120,8 +120,8 @@ namespace PrototypeInstancing
 namespace FVP_NS_DEF {
 
 DataProducerSceneIndexExample::DataProducerSceneIndexExample() :
-    _cubeRootPath(SdfPath(TfStringPrintf("/DataProducerSceneIndexExample/cube_%p", this))),//Is the root path for the cubes
-    _instancerPath(SdfPath(TfStringPrintf("/DataProducerSceneIndexExample/instancer_%p", this)))//Is the instancer path when using instancing
+    _cubeRootPath(SdfPath(TfStringPrintf("/cube_%p", this))),//Is the root path for the cubes
+    _instancerPath(SdfPath(TfStringPrintf("/instancer_%p", this)))//Is the instancer path when using instancing
 {
     //Create the HdRetainedSceneIndex to be able to easily add primitives
     _retainedSceneIndex = HdRetainedSceneIndex::New();

lib/flowViewport/sceneIndex/fvpParentDataModifierSceneIndex.h

@@ -40,11 +40,10 @@ class ParentDataModifierSceneIndex : public HdSingleInputFilteringSceneIndexBase
 public:
     using ParentClass = HdSingleInputFilteringSceneIndexBase;
 
-    static ParentDataModifierSceneIndexRefPtr New(const HdSceneIndexBaseRefPtr& _inputSceneIndex){
-        return TfCreateRefPtr(new ParentDataModifierSceneIndex(_inputSceneIndex));
+    static ParentDataModifierSceneIndexRefPtr New(const HdSceneIndexBaseRefPtr& inputSceneIndex, const SdfPath& parentPath, const GfMatrix4d& transformMatrix, bool visible){
+        return TfCreateRefPtr(new ParentDataModifierSceneIndex(inputSceneIndex, parentPath, transformMatrix, visible));
     }
 
-    void SetParentPath              (const SdfPath& parentPath)         {_parentPath        = parentPath;}
     void SetParentTransformMatrix   (const GfMatrix4d& transformMatrix) {_transformMatrix   = transformMatrix;}
     void SetParentVisibility        (bool visible)                      {_visible           = visible;}
 
@@ -86,7 +85,8 @@ class ParentDataModifierSceneIndex : public HdSingleInputFilteringSceneIndexBase
     GfMatrix4d  _transformMatrix;
     bool        _visible = true;
 private:
-    ParentDataModifierSceneIndex(const HdSceneIndexBaseRefPtr& _inputSceneIndex) : ParentClass(_inputSceneIndex){}
+    ParentDataModifierSceneIndex(const HdSceneIndexBaseRefPtr& _inputSceneIndex, const SdfPath& parentPath, const GfMatrix4d& transformMatrix, bool visible) : 
+        ParentClass(_inputSceneIndex), _parentPath(parentPath), _transformMatrix(transformMatrix), _visible(visible) {}
 };
 
 } //End of namespace FVP_NS_DEF

lib/mayaHydra/hydraExtensions/sceneIndex/mayaHydraMayaDataProducerSceneIndexData.cpp

@@ -89,6 +89,10 @@ MayaDataProducerSceneIndexData::MayaDataProducerSceneIndexData(const FVP_NS_DEF:
         MObject* mObj = reinterpret_cast<MObject*>(_dccNode);
         _mObjHandle   = MObjectHandle(*mObj);
 
+        _mayaNodeDagPath  = MDagPath::getAPathTo(*mObj);
+
+        _CopyMayaNodeTransform();//Copy it so that the classes created in _CreateSceneIndexChainForDataProducerSceneIndex have the up to date matrix
+
         //The user provided a DCC node, it's a maya MObject in maya hydra
         _CreateSceneIndexChainForDataProducerSceneIndex();
 
@@ -97,8 +101,6 @@ MayaDataProducerSceneIndexData::MayaDataProducerSceneIndexData(const FVP_NS_DEF:
             _nodeMessageCallbackIds.append(cbId);
         }
 
-        _mayaNodeDagPath  = MDagPath::getAPathTo(*mObj);
-
         //Also monitor parent DAG node to be able to update the scene index if the parent transform is modified or the visibility changed
         MDagPath parentDagPath  = _mayaNodeDagPath;
         parentDagPath.pop();
@@ -136,6 +138,12 @@ MayaDataProducerSceneIndexData::~MayaDataProducerSceneIndexData()
 }
 
 void MayaDataProducerSceneIndexData::UpdateTransformFromMayaNode() 
+{ 
+    _CopyMayaNodeTransform(); 
+    UpdateHydraTransformFromParentPath();
+}
+
+void MayaDataProducerSceneIndexData::_CopyMayaNodeTransform() 
 { 
     if (_mayaNodeDagPath.isValid()){
         //Get Maya transform value
@@ -144,9 +152,6 @@ void MayaDataProducerSceneIndexData::UpdateTransformFromMayaNode()
 
         //Copy Maya matrix into _parentMatrix member of this struct
         memcpy(_parentMatrix.GetArray(), mayaMat[0], sizeof(double) * 16);
-
-        //Update transform in Hydra
-        UpdateHydraTransformFromParentPath();
     }
 }
 

lib/mayaHydra/hydraExtensions/sceneIndex/mayaHydraMayaDataProducerSceneIndexData.h

@@ -57,6 +57,8 @@ TF_DECLARE_WEAK_AND_REF_PTRS(MayaDataProducerSceneIndexData);//Be able to use Re
 private:
     MayaDataProducerSceneIndexData(const FVP_NS_DEF::DataProducerSceneIndexDataBase::CreationParameters& params);
 
+    void _CopyMayaNodeTransform();
+
     //The following members are optional and used only when a dccNode was passed in the constructor of DataProducerSceneIndexDataBase
 
     /// Is the MObjectHandle of the maya node shape, it may be invalid if no maya node MObject pointer was passed.

test/lib/mayaUsd/render/mayaToHydra/cpp/testFlowViewportAPIAddPrims.cpp

@@ -60,7 +60,7 @@ TEST(FlowViewportAPI, addPrimitives)
     //hydraViewportDataProducerSceneIndexExample is what will inject the 3D grid of Hydra cube mesh primitives into the viewport
     Fvp::DataProducerSceneIndexExample  hydraViewportDataProducerSceneIndexExample;
 
-    const std::string firstCubePath (TfStringPrintf("/DataProducerSceneIndexExample/cube_%p0_0_0", &hydraViewportDataProducerSceneIndexExample));
+    const std::string firstCubePath (TfStringPrintf("/cube_%p0_0_0", &hydraViewportDataProducerSceneIndexExample));
 
     //Setup cube grid parameters
     hydraViewportDataProducerSceneIndexExample.setCubeGridParams(cubeGridParams);