Resyncs when authoring root xforms on PointInstancers

[asluk]

Currently, authoring root xforms on PointInstancer prims results in a full resync of the corresponding render index entries, due to https://github.com/PixarAnimationStudios/USD/blame/master/pxr/usdImaging/usdImaging/pointInstancerAdapter.cpp#L797 .

Filing this to be tracked, see discussion in https://groups.google.com/d/msg/usd-interest/dA9KhRJ1xfA/Ed3kffTHAwAJ

Repro case:

sphereInstancer.zip

Load asset in usdview, select the translate op on /World/Instancer, and then in the interpreter

Tf.Debug.SetDebugSymbolsByName("USDIMAGING_UPDATES", 1) Tf.Debug.SetDebugSymbolsByName("USDIMAGING_CHANGES", 1) usdview.property.Set((1,0,0))

This triggers a full resync as shown in the diagnostics below. Ideally this would be granular and retain all existing rprims. [Objects Changed] Notice recieved from stage with root layer @c:/Users/aluk/Downloads/sphereInstancer.usda@

• Resync queued: /World/Instancer.xformOp:translate [Objects Changed] Notice recieved from stage with root layer @c:/Users/aluk/Downloads/sphereInstancer.usda@
• Refresh queued: /World/Instancer.xformOp:translate [Update] Update for scene edits [Refresh Object]: /World/Instancer.xformOp:translate [ ]
  • affected prim: </World/Instancer>
  • affected prim: </World/Instancer>
  • affected prim: </World/Instancer.proto0_sphere_id0>
  • affected prim: </World/Instancer> [Remove Rprim] </World/Instancer.proto0_sphere_id0> [Remove Instancer] </World/Instancer> [Remove PrimInfo] </World/Instancer.proto0_sphere_id0> [Remove PrimInfo] </World/Instancer> [Remove dependency] </World/Instancer> -> </World/Instancer.proto0_sphere_id0> [Remove dependency] </World/Instancer/Dummy/sphere> -> </World/Instancer.proto0_sphere_id0> [Remove dependency] </World/Instancer> -> </World/Instancer> [Refresh Object]: /World/Instancer.xformOp:translate [ ] [Repopulate] Populating </> on stage sphereInstancer.usda [Repopulate] Root path: </World/Instancer> [Repopulate] Pruned children of </World/Instancer> due to adapter [Add HdPrim Info] </World/Instancer> adapter=UsdImagingPointInstancerAdapter [Add dependency] </World/Instancer> -> </World/Instancer> [Add HdPrim Info] </World/Instancer.proto0_sphere_id0> adapter=UsdImagingPointInstancerAdapter [Add dependency] </World/Instancer> -> </World/Instancer.proto0_sphere_id0> [Revert dependency] </World/Instancer> -> </World/Instancer.proto0_sphere_id0> [Add dependency] </World/Instancer/Dummy/sphere> -> </World/Instancer.proto0_sphere_id0> [Repopulate] 2 variability tasks in worker [Sync] PREP: </World/Instancer.proto0_sphere_id0> dirtyFlags: 0x9817ffc [ PrimID Extent DisplayStyle Points Primvar MaterialId Topology Transform Visibility Normals DoubleSided CullStyle SubdivTags Instancer NewRepr CustomBits:1001000] [Sync] PREP Instancer: </World/Instancer> dirtyFlags: 0x20240 [Primvar Transform InstanceIndex ]

[jtran56]

Filed as internal issue #USD-6077.