Disable tests and outline mode for MacOS

Author: julia-b-grenier

doc/outlineSelectionHighlightingArchitecture.md

@@ -44,7 +44,8 @@ return _isUsingHdSt && _globals.outlineSelectionHighlight;
   buffers and a GL compute shader for the mask, and gate themselves on Storm internally. A
   non-Storm delegate therefore keeps the legacy wireframe highlighting, whatever the global says.
 - **Not offered on USD 24.11**, where HgiGL corrupts the non-zero integer prim IDs the outline mask
-  shader samples. On that version the enum lists *Legacy Selection* only, and it is the default.
+  shader samples, **nor on macOS**, where outline selection highlighting is unsupported. In those
+  configurations the enum lists *Legacy Selection* only, and it is the default.
 
 Switching mode changes the scene index chain, so it cannot be done in place: `UpdateRenderGlobals()`
 flags `_needsClear`, and `Render()` runs `ClearHydraResources()` / `_InitHydraResources()` and then
@@ -348,7 +349,8 @@ thread.
 - **Storm only.** Other render delegates keep the legacy wireframe highlighting. Supporting a
   non-rasterizing delegate would mean a separate Storm pass rasterizing selected geometry alongside
   the beauty render and compositing the two — an HVT project, not a flag.
-- **Not available on USD 24.11**, where HgiGL corrupts the prim IDs the mask compute shader samples.
+- **Not available on USD 24.11**, where HgiGL corrupts the prim IDs the mask compute shader samples,
+  **or on macOS**, where outline selection highlighting is unsupported.
 - **Wireframe-on-shaded shows both cues.** Deliberate: the alternative was recolouring VP2's wire,
   and there is no correct dormant colour to recolour it to for non-mesh shapes.
 - **`enableDefaultOutlines` is off by default.** This is an HVT outline feature — a faint outline on

lib/mayaHydra/mayaPlugin/renderGlobals.cpp

@@ -40,6 +40,17 @@
 // This file is where we build the UI and expose to MEL the global parameters from this plug-in and
 // the parameters from the chosen render delegate.
 
+// The Outline selection-highlight mode is not offered in these configurations: the
+// mayaHydraSelectionHighlightMode enum lists "Legacy Selection" only, and it is the default.
+//  - USD <= 24.11: HgiGL corrupts the non-zero integer prim ids the outline compute shader samples.
+//  - macOS: outline selection highlighting is not supported.
+// Keep this in sync with MayaHydraBaseTestCase.outlineSelectionHighlightSupported() in
+// test/testUtils/mtohUtils.py and MAYAHYDRA_OUTLINE_MODE_AVAILABLE in
+// test/lib/mayaUsd/render/mayaToHydra/CMakeLists.txt.
+#if PXR_VERSION <= 2411 || defined(__APPLE__)
+#define MAYAHYDRA_NO_OUTLINE_SELECTION_HIGHLIGHT
+#endif
+
 PXR_NAMESPACE_OPEN_SCOPE
 // Bring the MayaHydra namespace into scope.
 // The following code currently lives inside the pxr namespace, but it would make more sense to 
@@ -974,9 +985,7 @@ MObject MtohRenderGlobals::CreateAttributes(const GlobalParams& params)
         }
     }
     if (filter(MtohTokens->mayaHydraSelectionHighlightMode)) {
-#if PXR_VERSION <= 2411
-        // USD 24.11's HgiGL corrupts non-zero integer prim ids sampled in the outline compute
-        // shader, so the Outline selection-highlight mode cannot work. Offer Legacy only.
+#ifdef MAYAHYDRA_NO_OUTLINE_SELECTION_HIGHLIGHT
         static const TfTokenVector kSelectionHighlightModes = { TfToken("Legacy Selection") };
 #else
         static const TfTokenVector kSelectionHighlightModes
@@ -986,7 +995,7 @@ MObject MtohRenderGlobals::CreateAttributes(const GlobalParams& params)
             node,
             filter.mayaString(),
             kSelectionHighlightModes,
-            kSelectionHighlightModes[0], // default = first entry (Legacy on 24.11, Outline otherwise)
+            kSelectionHighlightModes[0], // default = first entry, Legacy where Outline is unavailable
             userDefaults);
         if (filter.attributeFilter()) {
             return mayaObject;
@@ -1217,9 +1226,7 @@ MtohRenderGlobals::GetInstance(const GlobalParams& params, bool storeUserSetting
         }
     }
     if (filter(MtohTokens->mayaHydraSelectionHighlightMode)) {
-#if PXR_VERSION <= 2411
-        // On USD 24.11 the Outline mode is unsupported (see above / renderGlobals.cpp enum
-        // creation), so fall back to Legacy when the attribute is unset.
+#ifdef MAYAHYDRA_NO_OUTLINE_SELECTION_HIGHLIGHT
         TfToken mode("Legacy Selection");
 #else
         TfToken mode("Outline Selection");

test/lib/mayaUsd/render/mayaToHydra/CMakeLists.txt

@@ -26,7 +26,7 @@ set(INTERACTIVE_TEST_SCRIPT_FILES
     testMayaShadingModes.py|skipOnPlatform:osx # HYDRA-1127 : refinedWire not working on OSX
     testMayaDisplayLayers.py
     testMayaIsolateSelect.py
-    testOutlineHover.py
+    testOutlineHover.py|skipOnPlatform:osx # Outline selection highlighting is not available on macOS
 	#HYDRA-1940 temporarily disable this test which doesn't pass on Maya 2026
     #testMayaLights.py
     testUSDLights.py
@@ -209,10 +209,12 @@ set(INTERACTIVE_TEST_SCRIPT_FILES_ENABLE_GENERATIVE_PROCEDURAL
 # be mode-sensitive after all, one of its two runs fails against the shared image
 # instead of silently losing coverage.
 #
-# Outline is only offered on USD > 24.11: below that the render global has a
-# single "Legacy Selection" entry, because HgiGL corrupts the prim ids the outline
-# compute shader samples. Every primary run is then the legacy one.
-if(USD_VERSION VERSION_GREATER "0.24.11")
+# Outline is not offered everywhere: on USD <= 24.11 HgiGL corrupts the prim ids the
+# outline compute shader samples, and it is unsupported on macOS. In both cases the
+# render global has a single "Legacy Selection" entry, so every primary run is the
+# legacy one and there are no _legacy counterparts. Keep this in sync with
+# MAYAHYDRA_NO_OUTLINE_SELECTION_HIGHLIGHT in lib/mayaHydra/mayaPlugin/renderGlobals.cpp.
+if(USD_VERSION VERSION_GREATER "0.24.11" AND NOT IS_MACOSX)
     set(MAYAHYDRA_OUTLINE_MODE_AVAILABLE TRUE)
 else()
     set(MAYAHYDRA_OUTLINE_MODE_AVAILABLE FALSE)

test/testUtils/mtohUtils.py

@@ -45,12 +45,12 @@
 
 # Selection highlighting mode support.
 #
-# The mode is a defaultRenderGlobals enum attribute, and its entries depend on
-# the USD version: on USD > 24.11 it is
-# {"Outline Selection", "Legacy Selection"}, while on USD <= 24.11 only
-# {"Legacy Selection"} is offered, because 24.11's HgiGL cannot support the
-# outline compute shader (see renderGlobals.cpp). The enum indices therefore
-# differ between USD versions, so the index is resolved by name rather than
+# The mode is a defaultRenderGlobals enum attribute, and its entries depend on the
+# configuration: usually it is {"Outline Selection", "Legacy Selection"}, but only
+# {"Legacy Selection"} is offered on USD <= 24.11, because 24.11's HgiGL cannot
+# support the outline compute shader, and on macOS, where outline selection
+# highlighting is unsupported (see renderGlobals.cpp). The enum indices therefore
+# differ between configurations, so the index is resolved by name rather than
 # hardcoded.
 SELECTION_HIGHLIGHT_MODE_NAME = "mayaHydraSelectionHighlightMode"
 SELECTION_HIGHLIGHT_MODE_NODE = "defaultRenderGlobals"
@@ -99,16 +99,31 @@ class MayaHydraBaseTestCase(unittest.TestCase, ImageDiffingTestCase):
     # mayaUsdPlugin looged as HYDRA-1896, we should remove this when HYDRA-1896 is fixed
     _pluginsCantUnload = ['mayaHydraFlowViewportAPILocator', 'mtoa', 'modelingToolkit', 'mayaUsdPlugin']
 
+    @classmethod
+    def outlineSelectionHighlightSupported(cls):
+        '''Whether the outline mode is offered at all in this configuration.
+
+        Mirrors the MAYAHYDRA_NO_OUTLINE_SELECTION_HIGHLIGHT gate in
+        lib/mayaHydra/mayaPlugin/renderGlobals.cpp.
+        '''
+        if platform.system() == "Darwin":
+            return False
+        return Usd.GetVersion() > (0, 24, 11)
+
     @classmethod
     def selectionHighlightMode(cls):
         '''Return the selection highlighting mode this run should use.
 
-        Taken from the MAYAHYDRA_SELECTION_HIGHLIGHT_MODE environment variable,
-        defaulting to outline, which is what the plugin ships as its default.
+        Taken from the MAYAHYDRA_SELECTION_HIGHLIGHT_MODE environment variable.
+        With no variable set, this is outline, the mode the plugin ships as its
+        default, except where outline is not offered at all - see
+        outlineSelectionHighlightSupported().
         '''
         mode = os.environ.get(SELECTION_HIGHLIGHT_MODE_ENV_VAR, '').strip().lower()
         if not mode:
-            return SELECTION_HIGHLIGHT_MODE_OUTLINE
+            return (SELECTION_HIGHLIGHT_MODE_OUTLINE
+                    if cls.outlineSelectionHighlightSupported()
+                    else SELECTION_HIGHLIGHT_MODE_LEGACY)
         if mode not in SELECTION_HIGHLIGHT_MODE_ENUM_NAMES:
             raise ValueError(
                 "Unknown {} value {!r}; expected one of {}.".format(
@@ -416,13 +431,15 @@ def applySelectionHighlightMode(self):
             listEnum=True)[0].split(':')
 
         if wantedEnumName not in enumNames:
-            # On USD <= 24.11 only "Legacy Selection" is offered, so an outline
-            # run cannot be honoured. Skipping avoids silently comparing outline
+            # Where outline is not offered - USD <= 24.11, or macOS - only
+            # "Legacy Selection" exists, so an explicitly requested outline run
+            # cannot be honoured. Skipping avoids silently comparing outline
             # reference images against a legacy render.
             self.skipTest(
                 "Selection highlighting mode {!r} ({!r}) is not available on "
-                "USD {}; available modes: {}.".format(
-                    mode, wantedEnumName, str(self._usdVersion), enumNames))
+                "{} with USD {}; available modes: {}.".format(
+                    mode, wantedEnumName, platform.system(),
+                    str(self._usdVersion), enumNames))
 
         wantedIndex = enumNames.index(wantedEnumName)
         if cmds.getAttr(SELECTION_HIGHLIGHT_MODE_ATTR) == wantedIndex: