HYDRA-1058/HYDRA-970 : GeomSubsets picking filter + Fix multi-selection when single-picking

CMakeLists.txt

@@ -231,6 +231,11 @@ if(BUILD_HDSB_PLUGIN)
     endif()
 endif()
 
+#------------------------------------------------------------------------------
+# scripts
+#------------------------------------------------------------------------------
+add_subdirectory(scripts)
+
 #------------------------------------------------------------------------------
 # install
 #------------------------------------------------------------------------------

lib/mayaHydra/mayaPlugin/plugin.cpp

@@ -31,6 +31,7 @@
 
 #include <maya/MFnPlugin.h>
 #include <maya/MGlobal.h>
+#include <maya/MSceneMessage.h>
 
 #include <memory>
 #include <vector>
@@ -46,13 +47,6 @@
 
 using namespace MayaHydra;
 
-// Don't use smart pointers in the static vector: when Maya is doing its
-// default "quick exit" that does not uninitialize plugins, the atexit
-// destruction of the overrides in the vector will crash on destruction,
-// because Hydra has already destroyed structures these rely on.  Simply leak
-// the render overrides in this case.
-static std::vector<PXR_NS::MtohRenderOverride*> gsRenderOverrides;
-
 #if defined(MAYAHYDRA_VERSION)
 #define STRINGIFY(x)   #x
 #define TOSTRING(x)    STRINGIFY(x)
@@ -62,6 +56,20 @@ static std::vector<PXR_NS::MtohRenderOverride*> gsRenderOverrides;
 #define PLUGIN_VERSION "Maya-Hydra experimental"
 #endif
 
+namespace {
+    const std::string kMayaHydraPluginName = "mayaHydra";
+    const std::string kMayaUsdPluginName = "mayaUsdPlugin";
+
+    // Don't use smart pointers in the static vector: when Maya is doing its
+    // default "quick exit" that does not uninitialize plugins, the atexit
+    // destruction of the overrides in the vector will crash on destruction,
+    // because Hydra has already destroyed structures these rely on.  Simply leak
+    // the render overrides in this case.
+    std::vector<PXR_NS::MtohRenderOverride*> _renderOverrides;
+
+    std::vector<MCallbackId> _pluginLoadingCallbackIds;
+}
+
 void initialize()
 {
     Fvp::InitializationParams fvpInitParams;
@@ -83,6 +91,35 @@ void finalize()
     MayaHydra::MayaColorPreferencesTranslator::deleteInstance();
 }
 
+void afterPluginLoadCallback( const MStringArray& strs, void* clientData )
+{
+    for (const auto& str : strs) {
+        // If MayaUSD is being loaded, set up our GeomSubsets picking mode UI.
+        // This will re-create the "Select" menu callback if it has been previously torn down.
+        if (str.asChar() == kMayaUsdPluginName) {
+            MGlobal::executeCommand("if (`exists mayaHydra_GeomSubsetsPickMode_SetupUI`) { mayaHydra_GeomSubsetsPickMode_SetupUI; }");
+            break;
+        }
+    }
+}
+
+void beforePluginUnloadCallback( const MStringArray& strs, void* clientData )
+{
+    for (const auto& str : strs) {
+        // If MayaUSD is being unloaded, tear down our GeomSubsets picking mode UI.
+        // This resets the variables used to keep track of the UI elements' existence,
+        // and allows us to recreate them if MayaUSD is reloaded.
+        // We also do the same if mayaHydra is about to be unloaded : we can't rely on
+        // the deletion procedure registered through registerUI, as it seems the global 
+        // variables tracking our UI elements have been reset at that point for some reason.
+        auto strChar = str.asChar();
+        if (strChar == kMayaUsdPluginName || strChar == kMayaHydraPluginName) {
+            MGlobal::executeCommand("mayaHydra_GeomSubsetsPickMode_TeardownUI");
+            break;
+        }
+    }
+}
+
 PLUGIN_EXPORT MStatus initializePlugin(MObject obj)
 {
     MString experimental("mayaHydra is experimental.");
@@ -118,11 +155,54 @@ PLUGIN_EXPORT MStatus initializePlugin(MObject obj)
             auto    mtohRenderer = std::make_unique<PXR_NS::MtohRenderOverride>(desc);
             MStatus status = renderer->registerOverride(mtohRenderer.get());
             if (status == MS::kSuccess) {
-                gsRenderOverrides.push_back(mtohRenderer.release());
+                _renderOverrides.push_back(mtohRenderer.release());
             }
         }
     }
 
+    if (!plugin.registerUIStrings(nullptr, "mayaHydra_registerUIStrings")) {
+        ret = MS::kFailure;
+        ret.perror("Error registering mayaHydra UI string resources.");
+        return ret;
+    }
+
+    if (!plugin.registerUI(
+        "mayaHydra_registerUI_load",
+        "mayaHydra_registerUI_unload",
+        "mayaHydra_registerUI_batch_load",
+        "mayaHydra_registerUI_batch_unload"))
+    {
+        ret = MS::kFailure;
+        ret.perror("Error registering mayaHydra UI procedures.");
+        return ret;
+    }
+
+    auto registerPluginLoadingCallback = [&](MSceneMessage::Message pluginLoadingMessage, MMessage::MStringArrayFunction callback) {
+        MStatus callbackStatus;
+        MCallbackId callbackId = MSceneMessage::addStringArrayCallback(
+            pluginLoadingMessage, 
+            callback, 
+            nullptr, 
+            &callbackStatus);
+        if (callbackStatus) {
+            _pluginLoadingCallbackIds.push_back(callbackId);
+        } else {
+            ret = MS::kFailure;
+            ret.perror("Error registering mayaHydra plugin loading callback.");
+        }
+    };
+
+    std::vector<std::pair<MSceneMessage::Message, MMessage::MStringArrayFunction>> pluginLoadingCallbacks = {
+        {MSceneMessage::Message::kAfterPluginLoad, afterPluginLoadCallback},
+        {MSceneMessage::Message::kBeforePluginUnload, beforePluginUnloadCallback}
+    };
+    for (const auto& pluginLoadingCallback : pluginLoadingCallbacks) {
+        registerPluginLoadingCallback(pluginLoadingCallback.first, pluginLoadingCallback.second);
+        if (!ret) {
+            return ret;
+        }
+    }
+
     initialize();
 
     return ret;
@@ -132,19 +212,23 @@ PLUGIN_EXPORT MStatus uninitializePlugin(MObject obj)
 {
     finalize();
 
+    for (const auto& callbackId : _pluginLoadingCallbackIds) {
+        MSceneMessage::removeCallback(callbackId);
+    }
+
     MFnPlugin plugin(obj, "Autodesk", PLUGIN_VERSION, "Any");
     MStatus   ret = MS::kSuccess;
     if (auto* renderer = MHWRender::MRenderer::theRenderer()) {
-        for (unsigned int i = 0; i < gsRenderOverrides.size(); i++) {
-            renderer->deregisterOverride(gsRenderOverrides[i]);
-            delete gsRenderOverrides[i];
+        for (unsigned int i = 0; i < _renderOverrides.size(); i++) {
+            renderer->deregisterOverride(_renderOverrides[i]);
+            delete _renderOverrides[i];
         }
     }
 
-    gsRenderOverrides.clear();
+    _renderOverrides.clear();
 
     // Clear any registered callbacks
-    MGlobal::executeCommand("callbacks -cc mayaHydra;");
+    MGlobal::executeCommand("callbacks -cc -owner mayaHydra;");
 
     if (!plugin.deregisterCommand(MtohViewCmd::name)) {
         ret = MS::kFailure;