[hdPrman] Fix bug where non-color AOV's would receive

the rendering colorspace display filter transform.

The excludeAOVs list needs to include both the given name
and source name of AOV's due to how there may be multiple
display entries in RenderMan, using one form or the other.

(Internal change: 2420162)

Author: blevin

third_party/renderman/plugin/hdPrman/displayColorSpaceSceneIndexPlugin.cpp

@@ -121,6 +121,27 @@ _BuildExcludeAOVsList(const HdContainerDataSourceHandle& rsPrimDS)
                     // matching how HdPrman creates AOVs.
                     const SdfPath varPath = pathDs->GetTypedValue(0.0f);
                     uniqueAOVs.insert(varPath.GetName());
+
+                    // Also exclude the sourceName of the AOV, since it
+                    // make be created as an additional Display and
+                    // we need to ensure that PxrColorDisplayTransform
+                    // does not modify it.
+                    //
+                    // See testHdPrman_ColorSpaceExcludeAOVs for a test
+                    // where Ci, a, and "pos" (source: __Pworld) results in
+                    // 6 displays seen by PxrColorTransformDisplayFilter:
+                    //
+                    //   0: "Ci"
+                    //   1: "a"
+                    //   2: "Ci"
+                    //   3: "a"
+                    //   4: "pos"
+                    //   5: "__Pworld"
+                    //
+                    if (auto sourceNameDs = varSchema.GetSourceName()) {
+                        uniqueAOVs.insert(
+                            sourceNameDs->GetTypedValue(0.0f) );
+                    }
                 }
             }
         }