Adjust Hydra model schemas to address a recent performance

regression involving UsdImaging Native Instance Aggregation.

Aggregation uses Hydra model schemas as part of the aggregation
key.  Originally this only covered UsdGeomModelAPI, which holds
fields related to draw mode that must be considered when
determining instance aggregation.

Recently, to support other model-related capabiliites, I added
UsdModelAPI to this Hydra model schema.  The reasoning at the
time was to align with how the USD API schemas both use the same
"model:" namespace for their USD attributes.

However, the "modelPath" portion of this defeated aggregation
effectiveness, because otherwise-equivalent native instances
might have distinct modelPaths.

To address this, we first considered removing "modelPath",
which would fix the aggregation issue.  Clients wanting to
find the model path would simply need to traverse the scene
index to find the prim where the closest model schema
data source was introduced.

However, further discussion lead to considering that we should
keep the UsdModelAPI and UsdGeomModelAPI representations in Hydra
schemas distinct.  This change implements that, introducing a
GeomModel schema in Hydra.

(Internal change: 2303046)

pxr/usdImaging/usdImaging/CMakeLists.txt

@@ -55,6 +55,7 @@ pxr_library(usdImaging
         drawModeSceneIndex
         extentResolvingSceneIndex
         extentsHintSchema
+        geomModelSchema
         indexProxy
         materialParamUtils
         modelSchema

pxr/usdImaging/usdImaging/dataSourcePrim.cpp

@@ -26,6 +26,7 @@
 #include "pxr/usdImaging/usdImaging/dataSourcePrimvars.h"
 #include "pxr/usdImaging/usdImaging/dataSourceUsdPrimInfo.h"
 #include "pxr/usdImaging/usdImaging/extentsHintSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 #include "pxr/usdImaging/usdImaging/modelSchema.h"
 #include "pxr/usdImaging/usdImaging/tokens.h"
 #include "pxr/usdImaging/usdImaging/usdPrimInfoSchema.h"
@@ -556,7 +557,6 @@ UsdImagingDataSourcePrim_ModelAPI::GetNames()
         UsdImagingModelSchemaTokens->assetIdentifier,
         UsdImagingModelSchemaTokens->assetName,
         UsdImagingModelSchemaTokens->assetVersion,
-        UsdImagingModelSchemaTokens->applyDrawMode,
     };
 }
 
@@ -594,13 +594,6 @@ UsdImagingDataSourcePrim_ModelAPI::Get(const TfToken &name)
                 ::New(assetVersion);
         }
         return nullptr;
-    } else if (name == UsdImagingModelSchemaTokens->applyDrawMode) {
-        // We set applyDrawMode for kind = component prims even if the
-        // prim is not a UsdGeomModelAPI.
-        if (_model.IsKind(KindTokens->component)) {
-            return HdRetainedTypedSampledDataSource<bool>::New(true);
-        }
-        return nullptr;
     }
     return nullptr;
 }

pxr/usdImaging/usdImaging/drawModeSceneIndex.cpp

@@ -24,7 +24,7 @@
 #include "pxr/usdImaging/usdImaging/drawModeSceneIndex.h"
 #include "pxr/usdImaging/usdImaging/drawModeStandin.h"
 
-#include "pxr/usdImaging/usdImaging/modelSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 #include "pxr/usdImaging/usdImaging/usdPrimInfoSchema.h"
 
 #include "pxr/base/trace/trace.h"
@@ -64,18 +64,18 @@ _GetDrawMode(const HdSceneIndexPrim &prim)
         return empty;
     }
 
-    UsdImagingModelSchema modelSchema =
-        UsdImagingModelSchema::GetFromParent(prim.dataSource);
+    UsdImagingGeomModelSchema geomModelSchema =
+        UsdImagingGeomModelSchema::GetFromParent(prim.dataSource);
 
-    HdBoolDataSourceHandle const applySrc = modelSchema.GetApplyDrawMode();
+    HdBoolDataSourceHandle const applySrc = geomModelSchema.GetApplyDrawMode();
     if (!applySrc) {
         return empty;
     }
     if (!applySrc->GetTypedValue(0.0f)) {
         return empty;
     }
 
-    HdTokenDataSourceHandle const modeSrc = modelSchema.GetDrawMode();
+    HdTokenDataSourceHandle const modeSrc = geomModelSchema.GetDrawMode();
     if (!modeSrc) {
         return empty;
     }
@@ -357,10 +357,10 @@ UsdImagingDrawModeSceneIndex::_PrimsDirtied(
     std::set<SdfPath> paths;
 
     static const HdDataSourceLocatorSet drawModeLocators{
-        UsdImagingModelSchema::GetDefaultLocator().Append(
-            UsdImagingModelSchemaTokens->drawMode),
-        UsdImagingModelSchema::GetDefaultLocator().Append(
-            UsdImagingModelSchemaTokens->applyDrawMode)};
+        UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+            UsdImagingGeomModelSchemaTokens->drawMode),
+        UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+            UsdImagingGeomModelSchemaTokens->applyDrawMode)};
 
     for (const HdSceneIndexObserver::DirtiedPrimEntry &entry : entries) {
         if (drawModeLocators.Intersects(entry.dirtyLocators)) {

pxr/usdImaging/usdImaging/drawModeSceneIndex.h

@@ -37,7 +37,7 @@ TF_DECLARE_REF_PTRS(UsdImagingDrawModeSceneIndex);
 /// A scene index replacing geometry based on the draw mode.
 ///
 /// Inspects a prim's values for drawMode and applyDrawMode (see
-/// UsdImagingModelSchema).
+/// UsdImagingGeomModelSchema).
 /// If the drawMode is valid and not the default and applyDrawMode is true,
 /// the prim and all its descendents are replaced by stand-in geometry
 /// specified by the draw mode.

pxr/usdImaging/usdImaging/drawModeStandin.cpp

@@ -23,7 +23,7 @@
 
 #include "pxr/usdImaging/usdImaging/drawModeStandin.h"
 
-#include "pxr/usdImaging/usdImaging/modelSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 #include "pxr/usdImaging/usdImaging/tokens.h"
 
 #include "pxr/imaging/hd/basisCurvesSchema.h"
@@ -193,12 +193,12 @@ class _DisplayColorVec3fDataSource final : public HdVec3fDataSource
     }
 
 private:
-    _DisplayColorVec3fDataSource(const UsdImagingModelSchema schema)
+    _DisplayColorVec3fDataSource(const UsdImagingGeomModelSchema schema)
       : _schema(schema)
     {
     }
 
-    UsdImagingModelSchema _schema;
+    UsdImagingGeomModelSchema _schema;
 };
 
 /// A vec4f wrapper around a HdVec3fDataSource, for use when a vec4f
@@ -332,7 +332,7 @@ class _PrimvarsDataSource : public HdContainerDataSource
             ///
             return _PrimvarDataSource::New(
                 _DisplayColorVec3fDataSource::New(
-                    UsdImagingModelSchema::GetFromParent(_primSource)),
+                    UsdImagingGeomModelSchema::GetFromParent(_primSource)),
                 HdPrimvarSchemaTokens->constant,
                 HdPrimvarSchemaTokens->color);
         }
@@ -656,8 +656,8 @@ class _BoundsStandin : public UsdImaging_DrawModeStandin
 
         // Check whether model:drawModeColor is dirty.
         static const HdDataSourceLocator colorLocator =
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->drawModeColor);
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->drawModeColor);
         const bool dirtyColor =
             dirtyLocators.Intersects(colorLocator);
 
@@ -868,8 +868,8 @@ class _OriginStandin : public UsdImaging_DrawModeStandin
 
         // Check whether model:drawModeColor is dirty.
         static const HdDataSourceLocator colorLocator =
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->drawModeColor);
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->drawModeColor);
         const bool dirtyColor =
             dirtyLocators.Intersects(colorLocator);
 
@@ -950,7 +950,7 @@ using _MaterialsDict = std::unordered_map<
 /// It is providing a mesh with a material. The mesh consists of up to 6 quads.
 /// Besides points, it has the vertex-varying cardsUv and face-varying
 /// cardsTexAssgin - determining where to sample which of the up to 6 textures
-/// that can be specified by the UsdImagingModelSchema.
+/// that can be specified by the UsdImagingGeomModelSchema.
 ///
 /// Details vary based on the card geometry which is box, cross, or fromTexture.
 ///
@@ -1007,7 +1007,7 @@ class _CardsDataCache
     }
 
 private:
-    /// A helper extracing values from UsdImagingModelSchema.
+    /// A helper extracing values from UsdImagingGeomModelSchema.
     ///
     /// Note that the order of the six given textures is assumed to be:
     /// XPos, YPos, ZPos, XNeg, YNeg, ZNeg.
@@ -1018,7 +1018,7 @@ class _CardsDataCache
     /// So we do not support motion-blur for these attributes.
     struct _SchemaValues
     {
-        _SchemaValues(UsdImagingModelSchema schema);
+        _SchemaValues(UsdImagingGeomModelSchema schema);
 
         /// Card geometry, that is box, cross, or fromTexture.
         TfToken cardGeometry;
@@ -1081,7 +1081,7 @@ class _CardsDataCache
             return cached;
         }
         auto data = std::make_shared<_CardsData>(
-            _SchemaValues(UsdImagingModelSchema::GetFromParent(_primSource)),
+            _SchemaValues(UsdImagingGeomModelSchema::GetFromParent(_primSource)),
             _primPath
         );
 
@@ -1199,7 +1199,7 @@ GetWorldToScreenFromImageMetadata(
     return false;
 }
 
-_CardsDataCache::_SchemaValues::_SchemaValues(UsdImagingModelSchema schema)
+_CardsDataCache::_SchemaValues::_SchemaValues(UsdImagingGeomModelSchema schema)
 {
     if (HdTokenDataSourceHandle src = schema.GetCardGeometry()) {
         cardGeometry = src->GetTypedValue(0.0f);
@@ -2054,20 +2054,20 @@ class _CardsStandin : public UsdImaging_DrawModeStandin
         // we send to the observer.
 
         static const HdDataSourceLocatorSet cardLocators{
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardGeometry),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureXPos),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureYPos),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureZPos),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureXNeg),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureYNeg),
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->cardTextureZNeg) };
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardGeometry),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureXPos),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureYPos),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureZPos),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureXNeg),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureYNeg),
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->cardTextureZNeg) };
 
         // Blast the entire thing.
         if (dirtyLocators.Intersects(cardLocators)) {
@@ -2081,8 +2081,8 @@ class _CardsStandin : public UsdImaging_DrawModeStandin
         }
 
         static const HdDataSourceLocator colorLocator =
-            UsdImagingModelSchema::GetDefaultLocator().Append(
-                UsdImagingModelSchemaTokens->drawModeColor);
+            UsdImagingGeomModelSchema::GetDefaultLocator().Append(
+                UsdImagingGeomModelSchemaTokens->drawModeColor);
         if (dirtyLocators.Intersects(colorLocator)) {
             HdDataSourceLocatorSet primDirtyLocators = dirtyLocators;
             static const HdDataSourceLocator displayColorValue =

pxr/usdImaging/usdImaging/flattenedDataSourceProviders.cpp

@@ -24,7 +24,7 @@
 #include "pxr/usdImaging/usdImaging/flattenedDataSourceProviders.h"
 
 #include "pxr/usdImaging/usdImaging/flattenedModelDataSourceProvider.h"
-#include "pxr/usdImaging/usdImaging/modelSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 
 #include "pxr/imaging/hd/flattenedDataSourceProviders.h"
 #include "pxr/imaging/hd/overlayContainerDataSource.h"
@@ -40,7 +40,7 @@ UsdImagingFlattenedDataSourceProviders()
     static HdContainerDataSourceHandle const result =
         HdOverlayContainerDataSource::New(
         HdRetainedContainerDataSource::New(
-            UsdImagingModelSchema::GetSchemaToken(),
+            UsdImagingGeomModelSchema::GetSchemaToken(),
             Make<UsdImagingFlattenedModelDataSourceProvider>()),
         HdFlattenedDataSourceProviders());
     return result;

pxr/usdImaging/usdImaging/flattenedModelDataSourceProvider.cpp

@@ -23,7 +23,7 @@
 
 #include "pxr/usdImaging/usdImaging/flattenedModelDataSourceProvider.h"
 
-#include "pxr/usdImaging/usdImaging/modelSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 
 #include "pxr/usd/usdGeom/tokens.h"
 
@@ -35,7 +35,7 @@ bool
 _ContainsDrawMode(const TfTokenVector &vec)
 {
     for (const TfToken &token : vec) {
-        if (token == UsdImagingModelSchemaTokens->drawMode) {
+        if (token == UsdImagingGeomModelSchemaTokens->drawMode) {
             return true;
         }
     }
@@ -51,24 +51,24 @@ class _ModelDataSource : public HdContainerDataSource
         TfTokenVector result = _primModel->GetNames();
         if (!_ContainsDrawMode(result) &&
              _ContainsDrawMode(_parentModel->GetNames())) {
-            result.push_back(UsdImagingModelSchemaTokens->drawMode);
+            result.push_back(UsdImagingGeomModelSchemaTokens->drawMode);
         }
 
         return result;
     }
 
     HdDataSourceBaseHandle Get(const TfToken &name) override {
-        if (name != UsdImagingModelSchemaTokens->drawMode) {
+        if (name != UsdImagingGeomModelSchemaTokens->drawMode) {
             return _primModel->Get(name);
         }
         if (HdTokenDataSourceHandle ds =
-               UsdImagingModelSchema(_primModel).GetDrawMode()) {
+               UsdImagingGeomModelSchema(_primModel).GetDrawMode()) {
             const TfToken drawMode = ds->GetTypedValue(0.0f);
             if (!drawMode.IsEmpty() && drawMode != UsdGeomTokens->inherited) {
                 return ds;
             }
         }
-        return UsdImagingModelSchema(_parentModel).GetDrawMode();
+        return UsdImagingGeomModelSchema(_parentModel).GetDrawMode();
     }
 
     static
@@ -118,7 +118,7 @@ UsdImagingFlattenedModelDataSourceProvider::ComputeDirtyLocatorsForDescendants(
     HdDataSourceLocatorSet * const locators) const
 {
     static const HdDataSourceLocator drawModeLocator(
-        UsdImagingModelSchemaTokens->drawMode);
+        UsdImagingGeomModelSchemaTokens->drawMode);
     static const HdDataSourceLocatorSet drawModeLocatorSet{
         drawModeLocator};
 

pxr/usdImaging/usdImaging/geomModelAPIAdapter.cpp

@@ -24,13 +24,15 @@
 #include "pxr/usdImaging/usdImaging/geomModelAPIAdapter.h"
 
 #include "pxr/usdImaging/usdImaging/dataSourceSchemaBased.h"
-#include "pxr/usdImaging/usdImaging/modelSchema.h"
+#include "pxr/usdImaging/usdImaging/geomModelSchema.h"
 #include "pxr/usdImaging/usdImaging/tokens.h"
 #include "pxr/imaging/hd/extentSchema.h"
 #include "pxr/imaging/hd/overlayContainerDataSource.h"
 #include "pxr/imaging/hd/tokens.h"
 #include "pxr/imaging/hd/retainedDataSource.h"
+#include "pxr/usd/kind/registry.h"
 #include "pxr/usd/usdGeom/modelAPI.h"
+#include "pxr/usd/usd/modelAPI.h"
 
 PXR_NAMESPACE_OPEN_SCOPE
 
@@ -54,7 +56,7 @@ struct _GeomModelTranslator
     HdDataSourceLocator
     GetContainerLocator()
     {
-        return UsdImagingModelSchema::GetDefaultLocator();
+        return UsdImagingGeomModelSchema::GetDefaultLocator();
     }
 };    
 
@@ -82,12 +84,25 @@ UsdImagingGeomModelAPIAdapter::GetImagingSubprimData(
     }
 
     if (subprim.IsEmpty()) {
-        UsdGeomModelAPI model(prim);
+        // Reflect UsdGeomModelAPI as UsdImagingGeomModelSchema.
+        HdContainerDataSourceHandle geomModelDs =
+            HdRetainedContainerDataSource::New(
+                UsdImagingGeomModelSchema::GetSchemaToken(),
+                _GeomModelDataSource::New(
+                    prim.GetPath(), UsdGeomModelAPI(prim), stageGlobals));
+
+        // For model components, overlay applyDrawMode=true.
+        if (UsdModelAPI(prim).IsKind(KindTokens->component)) {
+            static HdContainerDataSourceHandle const applyDrawModeDs =
+                UsdImagingGeomModelSchema::Builder()
+                    .SetApplyDrawMode(
+                        HdRetainedTypedSampledDataSource<bool>::New(true))
+                    .Build();
+            geomModelDs = HdOverlayContainerDataSource::
+                OverlayedContainerDataSources(applyDrawModeDs, geomModelDs);
+        }
 
-        return HdRetainedContainerDataSource::New(
-            UsdImagingModelSchema::GetSchemaToken(),
-            _GeomModelDataSource::New(
-                prim.GetPath(), model, stageGlobals));
+        return geomModelDs;
     }
 
     return nullptr;