[Rendering Debugger] GPU Resident Drawer : Avoid recreating the tool on messageCallback when the state of initialization changes.

Author: alex-vazquez-unity3d

Packages/com.unity.render-pipelines.core/Runtime/Debugging/DebugUI.Panel.cs

@@ -56,6 +56,7 @@ public VisualElement Create(DebugUI.Context context)
                 container.AddToClassList("unity-inspector-element");
 
                 var content = new VisualElement();
+
                 foreach (var child in children)
                 {
                     if (context == Context.Editor && child.isRuntimeOnly)
@@ -67,6 +68,7 @@ public VisualElement Create(DebugUI.Context context)
                     if (childUIElement != null)
                         content.Add(childUIElement);
                 }
+
                 container.Add(content);
 
                 return container;

Packages/com.unity.render-pipelines.core/Runtime/GPUDriven/Debug/DebugDisplayGPUResidentDrawer.cs

@@ -234,15 +234,11 @@ private static DebugUI.Table.Row AddOcclusionContextDataRow(int index)
             };
         }
 
-        static bool s_GRDWasEnabled;
-
         [DisplayInfo(name = "Rendering", order = 5)]
         private class SettingsPanel : DebugDisplaySettingsPanel
         {
             public SettingsPanel(DebugDisplayGPUResidentDrawer data)
             {
-                s_GRDWasEnabled = GPUResidentDrawer.IsInitialized();
-
                 DocumentationUtils.TryGetHelpURL(typeof(DebugDisplayGPUResidentDrawer), out var documentationUrl);
                 var foldout = new DebugUI.Foldout()
                 {
@@ -257,21 +253,16 @@ public SettingsPanel(DebugDisplayGPUResidentDrawer data)
                     style = MessageBox.Style.Warning,
                     messageCallback = () =>
                     {
-                        // HACK: Reload the UI if GRD enabled state changes
-                        if (s_GRDWasEnabled != GPUResidentDrawer.IsInitialized())
-                        {
-                            s_GRDWasEnabled = GPUResidentDrawer.IsInitialized();
-                            DebugManager.instance.Reset();
-                        }
-
                         var settings = GPUResidentDrawer.GetGlobalSettingsFromRPAsset();
                         return GPUResidentDrawer.IsGPUResidentDrawerSupportedBySRP(settings, out var msg, out var _) ? string.Empty : msg;
                     },
                     isHiddenCallback = () => GPUResidentDrawer.IsInitialized()
                 };
                 foldout.children.Add(helpBox);
 
-                // HACK: Avoid creating GRD debug modes when it's not enabled.
+                GPUResidentDrawer.initializedChanged += OnGPUResidentDrawerInitialzedChanged;
+
+                // Avoid creating GRD debug modes when it's not enabled.
                 // This debug UI currently creates ~650 DebugUI Widgets (over 80% of all debug widgets in URP).
                 // To avoid the overhead, we don't create them if GRD is not enabled. If GRD gets enabled while window is open,
                 // we refresh the window. It would probably be a good idea to rethink how the stats tables are implemented.
@@ -307,6 +298,21 @@ public SettingsPanel(DebugDisplayGPUResidentDrawer data)
                 AddInstanceCullingStatsWidget(data);
             }
 
+            private void OnGPUResidentDrawerInitialzedChanged(bool previousValue, bool currentValue)
+            {
+                // Reload the UI if GRD enabled state changes, from disabled to enabled only, as the UI did not have all the widgets and we need to add them
+                // in assembly reloads, or entering playmode we do not have this code path and the SettingsPanel will be recreated itself by the Rendering Debugger
+                // reconstruction.
+                if ( previousValue == false && currentValue == true )
+                    DebugManager.instance.Reset();
+            }
+
+            public override void Dispose()
+            {
+                base.Dispose();
+                GPUResidentDrawer.initializedChanged -= OnGPUResidentDrawerInitialzedChanged;
+            }
+
             private void AddInstanceCullingStatsWidget(DebugDisplayGPUResidentDrawer data)
             {
                 var instanceCullerStats = new DebugUI.Foldout

Packages/com.unity.render-pipelines.core/Runtime/GPUDriven/GPUResidentDrawer.cs

@@ -340,6 +340,8 @@ internal static void Reinitialize()
 #endif
         }
 
+        internal static Action<bool, bool> initializedChanged; // previousValue, currentValue
+
         private static void Cleanup()
         {
             if (s_Instance == null)
@@ -352,6 +354,8 @@ private static void Cleanup()
 
         private static void Recreate(GPUResidentDrawerSettings settings)
         {
+            bool wasInitialized = IsInitialized();
+
             Cleanup();
 
             if (IsGPUResidentDrawerSupportedBySRP(settings, out var message, out var severity))
@@ -363,6 +367,10 @@ private static void Recreate(GPUResidentDrawerSettings settings)
             {
                 LogMessage(message, severity);
             }
+
+            bool isInitialized = IsInitialized();
+            if (wasInitialized != isInitialized)
+                initializedChanged?.Invoke(wasInitialized, isInitialized);
         }
 
         private IntPtr m_ContextIntPtr = IntPtr.Zero;