UsdRender/UsdRi: Move the matte and cameraVisibility collections

from UsdRiRenderPassAPI to UsdRenderPass, and remove
UsdRiRenderPassAPI.  There are several motivations here:

1. These two collections were an exception to the principle
   that all RenderMan concepts represented as USD attributes
   use the "ri:" namespace; and that API schemas broadly
   should use namespaces to avoid domain collisions.

2. UsdRiRenderPassAPI, being an auto-applied API schema in
   the core USD distribution, was contributing these collections
   to render passes even when RenderMan was not in use.
   This proved awkward in environments where a different
   renderer was in use that also supported these same
   concepts of matte and cameraVisibility.

3. This recognizes that matte objects and camera visibility
   are broadly supported and useful notions in CG production
   rendering.  It also recognizes that these collections are
   not inherently implemented in a renderer, but instead are
   implemented in the scene-generation side of the rendering
   system (e.g. Hydra), by being mapped to renderer-specific
   concepts (ri:Matte and ri:visibility:camera in the case
   of RenderMan).

4. This change requires no asset updates and is simply
   rationalizing existing schemas, informed by experience.

(Internal change: 2361095)

Author: blevin

pxr/usd/usdRender/generatedSchema.usda

@@ -400,9 +400,9 @@ class RenderProduct "RenderProduct" (
 }
 
 class RenderPass "RenderPass" (
-    apiSchemas = ["CollectionAPI:renderVisibility", "CollectionAPI:prune"]
+    apiSchemas = ["CollectionAPI:renderVisibility", "CollectionAPI:cameraVisibility", "CollectionAPI:prune", "CollectionAPI:matte"]
     customData = {
-        token[] apiSchemaOverridePropertyNames = ["collection:renderVisibility:includeRoot"]
+        token[] apiSchemaOverridePropertyNames = ["collection:cameraVisibility:includeRoot", "collection:renderVisibility:includeRoot"]
     }
     doc = """A RenderPass prim encapsulates necessary information
     to generate multi-pass renders.  In a multi-pass render, multiple
@@ -454,6 +454,20 @@ class RenderPass "RenderPass" (
     to objects associated with the render settings, such as image
     post-processing filters, even when UsdGeomVisibilityAPI may apply.
 
+    \\anchor usdRi_cameraVisibility
+    The cameraVisibility collection defines which scene objects should
+    be directly visible in camera.  Objects that are not in this
+    collection should still participate in other light paths such
+    as shadowing, reflections, and refraction.  By default everything in
+    the scene should be visible to camera, so this collection sets
+    includeRoot to 1.
+
+    \\anchor usdRi_matte
+    The matte collection defines scene objects that should act as
+    matte objects.  Matte objects render with zero alpha.  By
+    default, everything in the scene should render normally, so
+    this collection sets includeRoot to 0.
+
     \\anchor usdRender_pruning
     The prune collection specifies a collection of objects to be removed
     (\"pruned\") from the scene prior to rendering.  Whereas visibility
@@ -470,6 +484,7 @@ class RenderPass "RenderPass" (
     """
 )
 {
+    uniform bool collection:cameraVisibility:includeRoot = 1
     uniform bool collection:renderVisibility:includeRoot = 1
     uniform string[] command (
         doc = '''The command to run in order to generate

pxr/usd/usdRender/pass.h

@@ -87,6 +87,20 @@ class SdfAssetPath;
 /// to objects associated with the render settings, such as image
 /// post-processing filters, even when UsdGeomVisibilityAPI may apply.
 /// 
+/// \anchor usdRi_cameraVisibility
+/// The cameraVisibility collection defines which scene objects should
+/// be directly visible in camera.  Objects that are not in this
+/// collection should still participate in other light paths such
+/// as shadowing, reflections, and refraction.  By default everything in
+/// the scene should be visible to camera, so this collection sets
+/// includeRoot to 1.
+/// 
+/// \anchor usdRi_matte
+/// The matte collection defines scene objects that should act as
+/// matte objects.  Matte objects render with zero alpha.  By
+/// default, everything in the scene should render normally, so
+/// this collection sets includeRoot to 0.
+/// 
 /// \anchor usdRender_pruning
 /// The prune collection specifies a collection of objects to be removed
 /// ("pruned") from the scene prior to rendering.  Whereas visibility

pxr/usd/usdRender/schema.usda

@@ -315,6 +315,20 @@ class RenderPass "RenderPass" (
     to objects associated with the render settings, such as image
     post-processing filters, even when UsdGeomVisibilityAPI may apply.
 
+    \\anchor usdRi_cameraVisibility
+    The cameraVisibility collection defines which scene objects should
+    be directly visible in camera.  Objects that are not in this
+    collection should still participate in other light paths such
+    as shadowing, reflections, and refraction.  By default everything in
+    the scene should be visible to camera, so this collection sets
+    includeRoot to 1.
+
+    \\anchor usdRi_matte
+    The matte collection defines scene objects that should act as
+    matte objects.  Matte objects render with zero alpha.  By
+    default, everything in the scene should render normally, so
+    this collection sets includeRoot to 0.
+
     \\anchor usdRender_pruning
     The prune collection specifies a collection of objects to be removed
     ("pruned") from the scene prior to rendering.  Whereas visibility
@@ -334,7 +348,7 @@ class RenderPass "RenderPass" (
          string extraIncludes = """
 #include "pxr/usd/usd/collectionAPI.h" """
     }
-    prepend apiSchemas = ["CollectionAPI:renderVisibility", "CollectionAPI:prune"]
+    prepend apiSchemas = ["CollectionAPI:renderVisibility", "CollectionAPI:cameraVisibility", "CollectionAPI:prune", "CollectionAPI:matte"]
 ) {
     uniform token passType (
         doc = """A string used to categorize differently structured 
@@ -414,4 +428,9 @@ class RenderPass "RenderPass" (
             bool apiSchemaOverride = true
         }
     )
+    uniform bool collection:cameraVisibility:includeRoot = 1 (
+        customData = {
+            bool apiSchemaOverride = true
+        }
+    )
 }

pxr/usd/usdRender/tokens.cpp

@@ -14,6 +14,7 @@ UsdRenderTokensType::UsdRenderTokensType() :
     adjustPixelAspectRatio("adjustPixelAspectRatio", TfToken::Immortal),
     aspectRatioConformPolicy("aspectRatioConformPolicy", TfToken::Immortal),
     camera("camera", TfToken::Immortal),
+    collectionCameraVisibilityIncludeRoot("collection:cameraVisibility:includeRoot", TfToken::Immortal),
     collectionRenderVisibilityIncludeRoot("collection:renderVisibility:includeRoot", TfToken::Immortal),
     color3f("color3f", TfToken::Immortal),
     command("command", TfToken::Immortal),
@@ -60,6 +61,7 @@ UsdRenderTokensType::UsdRenderTokensType() :
         adjustPixelAspectRatio,
         aspectRatioConformPolicy,
         camera,
+        collectionCameraVisibilityIncludeRoot,
         collectionRenderVisibilityIncludeRoot,
         color3f,
         command,

pxr/usd/usdRender/tokens.h

@@ -65,6 +65,10 @@ struct UsdRenderTokensType {
     /// 
     /// UsdRenderSettingsBase
     const TfToken camera;
+    /// \brief "collection:cameraVisibility:includeRoot"
+    /// 
+    /// UsdRenderPass
+    const TfToken collectionCameraVisibilityIncludeRoot;
     /// \brief "collection:renderVisibility:includeRoot"
     /// 
     /// UsdRenderPass

pxr/usd/usdRender/wrapTokens.cpp

@@ -22,6 +22,7 @@ void wrapUsdRenderTokens()
     _ADD_TOKEN(cls, adjustPixelAspectRatio);
     _ADD_TOKEN(cls, aspectRatioConformPolicy);
     _ADD_TOKEN(cls, camera);
+    _ADD_TOKEN(cls, collectionCameraVisibilityIncludeRoot);
     _ADD_TOKEN(cls, collectionRenderVisibilityIncludeRoot);
     _ADD_TOKEN(cls, color3f);
     _ADD_TOKEN(cls, command);

pxr/usd/usdRi/generatedSchema.classes.txt

@@ -2,15 +2,13 @@
 
 # Public Classes
 materialAPI
-renderPassAPI
 splineAPI
 statementsAPI
 tokens
 
 # Python Module Files
 module.cpp
 wrapMaterialAPI.cpp
-wrapRenderPassAPI.cpp
 wrapSplineAPI.cpp
 wrapStatementsAPI.cpp
 wrapTokens.cpp

pxr/usd/usdRi/generatedSchema.module.h

@@ -9,5 +9,4 @@
 TF_WRAP(UsdRiStatementsAPI);
 TF_WRAP(UsdRiMaterialAPI);
 TF_WRAP(UsdRiSplineAPI);
-TF_WRAP(UsdRiRenderPassAPI);
 TF_WRAP(UsdRiTokens);

pxr/usd/usdRi/generatedSchema.usda

@@ -63,32 +63,3 @@ class "RiSplineAPI" (
 {
 }
 
-class "RiRenderPassAPI" (
-    apiSchemas = ["CollectionAPI:matte", "CollectionAPI:cameraVisibility"]
-    customData = {
-        token[] apiSchemaOverridePropertyNames = ["collection:cameraVisibility:includeRoot"]
-    }
-    doc = """
-    RiRenderPassAPI is an API schema that provides a mechanism
-    to set certain Ri statements on each prim in a collection,
-    for a given RenderPass prim.
-
-    \\anchor usdRi_cameraVisibility
-    The objects that are relevant to the render is specified via the 
-    cameraVisibility collection (UsdCollectionAPI) and can be accessed via 
-    GetCameraVisibilityCollectionAPI(). Each prim in the collection will have
-    ri:visible:camera set to 1.  By default everything in the scene should be 
-    visible to camera, so this collection sets includeRoot to 1.
-
-    \\anchor usdRi_matte
-    The objects that are relevant to the render is specified via the 
-    matte collection (UsdCollectionAPI) and can be accessed via 
-    GetMatteCollectionAPI().  Each prim in the collection will have
-    ri:matte set to 1.  By default everything in the scene should render
-    normally, so this collection sets includeRoot to 0.
-    """
-)
-{
-    uniform bool collection:cameraVisibility:includeRoot = 1
-}
-

pxr/usd/usdRi/plugInfo.json

@@ -17,23 +17,6 @@
                         "schemaIdentifier": "RiMaterialAPI", 
                         "schemaKind": "singleApplyAPI"
                     }, 
-                    "UsdRiRenderPassAPI": {
-                        "alias": {
-                            "UsdSchemaBase": "RiRenderPassAPI"
-                        }, 
-                        "apiSchemaAutoApplyTo": [
-                            "RenderPass"
-                        ], 
-                        "apiSchemaCanOnlyApplyTo": [
-                            "RenderPass"
-                        ], 
-                        "autoGenerated": true, 
-                        "bases": [
-                            "UsdAPISchemaBase"
-                        ], 
-                        "schemaIdentifier": "RiRenderPassAPI", 
-                        "schemaKind": "singleApplyAPI"
-                    }, 
                     "UsdRiSplineAPI": {
                         "alias": {
                             "UsdSchemaBase": "RiSplineAPI"