EMSUSD-708 fix performance of instanceable prims

Call the Usdimaging function to retrieve all instance prim path at once instead of one-by-one, which optimizes many internal details. - Use the same faster code in a few other similar places. - Add a convenience function to retrieve all the prim paths when the instance ID are consecutives. - Use it in a few places.
Autodesk · Feb 12, 2024 · e61812f · e61812f
1 parent d68d172
commit e61812f
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Showing 5 changed files with 44 additions and 7 deletions.
diff --git a/lib/mayaUsd/render/vp2RenderDelegate/basisCurves.cpp b/lib/mayaUsd/render/vp2RenderDelegate/basisCurves.cpp
@@ -910,12 +910,12 @@ void HdVP2BasisCurves::_UpdateDrawItem(
         if (0 == instanceCount) {
             instancerWithNoInstances = true;
         } else {
+            const SdfPathVector usdPaths = drawScene.GetScenePrimPaths(id, instanceCount);
             stateToCommit._instanceTransforms->setLength(instanceCount);
             for (unsigned int i = 0; i < instanceCount; ++i) {
                 transforms[i].Get(instanceMatrix.matrix);
                 (*stateToCommit._instanceTransforms)[i] = worldMatrix * instanceMatrix;
-                stateToCommit._ufeIdentifiers.append(
-                    drawScene.GetScenePrimPath(GetId(), i).GetString().c_str());
+                stateToCommit._ufeIdentifiers.append(usdPaths[i].GetString().c_str());
             }
 
             // If the item is used for both regular draw and selection highlight,

diff --git a/lib/mayaUsd/render/vp2RenderDelegate/mayaPrimCommon.cpp b/lib/mayaUsd/render/vp2RenderDelegate/mayaPrimCommon.cpp
@@ -808,9 +808,12 @@ void MayaUsdRPrim::_SyncDisplayLayerModesInstanced(SdfPath const& id, unsigned i
     _requiredModFlagsBitset.reset();
     if (_useInstancedDisplayLayerModes) {
         _displayLayerModesInstanced.resize(instanceCount);
+
+        const SdfPathVector usdPaths = drawScene.GetScenePrimPaths(id, instanceCount);
+
         for (unsigned int usdInstanceId = 0; usdInstanceId < instanceCount; usdInstanceId++) {
-            auto  usdPath = drawScene.GetScenePrimPath(id, usdInstanceId);
-            auto& displayLayerModes = _displayLayerModesInstanced[usdInstanceId];
+            auto&          displayLayerModes = _displayLayerModesInstanced[usdInstanceId];
+            const SdfPath& usdPath = usdPaths[usdInstanceId];
             _PopulateDisplayLayerModes(usdPath, displayLayerModes, drawScene);
 
             if (displayLayerModes._reprOverride == kBBox) {

diff --git a/lib/mayaUsd/render/vp2RenderDelegate/points.cpp b/lib/mayaUsd/render/vp2RenderDelegate/points.cpp
@@ -607,12 +607,12 @@ void HdVP2Points::_UpdateDrawItem(
         if (0 == instanceCount) {
             instancerWithNoInstances = true;
         } else {
+            const SdfPathVector usdPaths = drawScene.GetScenePrimPaths(id, instanceCount);
             stateToCommit._instanceTransforms->setLength(instanceCount);
             for (unsigned int i = 0; i < instanceCount; ++i) {
                 transforms[i].Get(instanceMatrix.matrix);
                 (*stateToCommit._instanceTransforms)[i] = worldMatrix * instanceMatrix;
-                stateToCommit._ufeIdentifiers.append(
-                    drawScene.GetScenePrimPath(GetId(), i).GetString().c_str());
+                stateToCommit._ufeIdentifiers.append(usdPaths[i].GetString().c_str());
             }
 
             // If the item is used for both regular draw and selection highlight,

diff --git a/lib/mayaUsd/render/vp2RenderDelegate/proxyRenderDelegate.cpp b/lib/mayaUsd/render/vp2RenderDelegate/proxyRenderDelegate.cpp
@@ -1343,6 +1343,37 @@ SdfPath ProxyRenderDelegate::GetScenePrimPath(const SdfPath& rprimId, int instan
     return usdPath;
 }
 
+static std::vector<int> fillInstanceIds(unsigned int instanceCount)
+{
+    std::vector<int> usdInstanceIds;
+    usdInstanceIds.reserve(instanceCount);
+    for (unsigned int usdInstanceId = 0; usdInstanceId < instanceCount; usdInstanceId++)
+        usdInstanceIds.emplace_back(usdInstanceId);
+    return usdInstanceIds;
+}
+
+SdfPathVector
+ProxyRenderDelegate::GetScenePrimPaths(const SdfPath& rprimId, unsigned int instanceCount) const
+{
+    return GetScenePrimPaths(rprimId, fillInstanceIds(instanceCount));
+}
+
+SdfPathVector ProxyRenderDelegate::GetScenePrimPaths(
+    const SdfPath&   rprimId,
+    std::vector<int> instanceIndexes) const
+{
+#if defined(USD_IMAGING_API_VERSION) && USD_IMAGING_API_VERSION >= 17
+    return _sceneDelegate->GetScenePrimPaths(rprimId, instanceIndexes);
+#else
+    SdfPathVector usdPaths;
+    usdPaths.reserve(instanceIndexes.size());
+    for (int instanceIndex : instanceIndexes) {
+        usdPaths.emplace_back(GetScenePrimPath(rprimId, instanceIndex));
+    }
+    return usdPaths;
+#endif
+}
+
 //! \brief  Selection for both instanced and non-instanced cases.
 bool ProxyRenderDelegate::getInstancedSelectionPath(
     const MHWRender::MRenderItem&   renderItem,
@@ -1395,7 +1426,7 @@ bool ProxyRenderDelegate::getInstancedSelectionPath(
         topLevelInstanceIndex = instancerContext.front().second;
     }
 #else
-    SdfPath usdPath = GetScenePrimPath(rprimId, instanceIndex);
+    SdfPath      usdPath = GetScenePrimPath(rprimId, instanceIndex);
 #endif
 
     // If update for selection is enabled, we can query the Maya selection list

diff --git a/lib/mayaUsd/render/vp2RenderDelegate/proxyRenderDelegate.h b/lib/mayaUsd/render/vp2RenderDelegate/proxyRenderDelegate.h
@@ -159,6 +159,9 @@ class ProxyRenderDelegate
     SdfPath GetScenePrimPath(const SdfPath& rprimId, int instanceIndex) const;
 #endif
 
+    SdfPathVector GetScenePrimPaths(const SdfPath& rprimId, std::vector<int> instanceIndexes) const;
+    SdfPathVector GetScenePrimPaths(const SdfPath& rprimId, unsigned int instanceCount) const;
+
     MAYAUSD_CORE_PUBLIC
     void SelectionChanged();