From d9ea329cbde12eb973a9942562c18ae40e5e052b Mon Sep 17 00:00:00 2001
From: amzn-sean <75276488+amzn-sean@users.noreply.github.com>
Date: Tue, 17 Aug 2021 13:48:51 +0100
Subject: [PATCH] Fixes #2796 Collider retains phys mesh asset reference after
 changing to shape (#3162)

Signed-off-by: amzn-sean <75276488+amzn-sean@users.noreply.github.com>
---
 .../PhysX/Code/Source/EditorColliderComponent.cpp | 15 ++++++++++++++-
 Gems/PhysX/Code/Source/EditorColliderComponent.h  |  9 ++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/Gems/PhysX/Code/Source/EditorColliderComponent.cpp b/Gems/PhysX/Code/Source/EditorColliderComponent.cpp
index d3f1c63974..2445aba9bd 100644
--- a/Gems/PhysX/Code/Source/EditorColliderComponent.cpp
+++ b/Gems/PhysX/Code/Source/EditorColliderComponent.cpp
@@ -88,7 +88,7 @@ namespace PhysX
                         ->EnumAttribute(Physics::ShapeType::Box, "Box")
                         ->EnumAttribute(Physics::ShapeType::Capsule, "Capsule")
                         ->EnumAttribute(Physics::ShapeType::PhysicsAsset, "PhysicsAsset")
-                        ->Attribute(AZ::Edit::Attributes::ChangeNotify, AZ::Edit::PropertyRefreshLevels::EntireTree)
+                        ->Attribute(AZ::Edit::Attributes::ChangeNotify, &EditorProxyShapeConfig::OnShapeTypeChanged)
                         // note: we do not want the user to be able to change shape types while in ComponentMode (there will
                         // potentially be different ComponentModes for different shape types)
                         ->Attribute(AZ::Edit::Attributes::ReadOnly, &AzToolsFramework::ComponentModeFramework::InComponentMode)
@@ -116,6 +116,19 @@ namespace PhysX
         }
     }
 
+    AZ::u32 EditorProxyShapeConfig::OnShapeTypeChanged()
+    {
+        //reset the physics asset if the shape type was Physics Asset
+        if (m_shapeType != Physics::ShapeType::PhysicsAsset &&
+            m_lastShapeType == Physics::ShapeType::PhysicsAsset)
+        {
+            m_physicsAsset.m_pxAsset.Reset();
+            m_physicsAsset.m_configuration = Physics::PhysicsAssetShapeConfiguration();
+        }
+        m_lastShapeType = m_shapeType;
+        return AZ::Edit::PropertyRefreshLevels::EntireTree;
+    }
+
     AZ::u32 EditorProxyShapeConfig::OnConfigurationChanged()
     {
         return AZ::Edit::PropertyRefreshLevels::ValuesOnly;
diff --git a/Gems/PhysX/Code/Source/EditorColliderComponent.h b/Gems/PhysX/Code/Source/EditorColliderComponent.h
index 8a78cc1cb8..50cf9d0c8b 100644
--- a/Gems/PhysX/Code/Source/EditorColliderComponent.h
+++ b/Gems/PhysX/Code/Source/EditorColliderComponent.h
@@ -58,8 +58,8 @@ namespace PhysX
     //! Proxy container for only displaying a specific shape configuration depending on the shapeType selected.
     struct EditorProxyShapeConfig
     {
-        AZ_CLASS_ALLOCATOR(EditorProxyShapeConfig, AZ::SystemAllocator, 0);
-        AZ_RTTI(EditorProxyShapeConfig, "{531FB42A-42A9-4234-89BA-FD349EF83D0C}");
+        AZ_CLASS_ALLOCATOR(PhysX::EditorProxyShapeConfig, AZ::SystemAllocator, 0);
+        AZ_RTTI(PhysX::EditorProxyShapeConfig, "{531FB42A-42A9-4234-89BA-FD349EF83D0C}");
         static void Reflect(AZ::ReflectContext* context);
 
         EditorProxyShapeConfig() = default;
@@ -84,9 +84,12 @@ namespace PhysX
 
         AZStd::shared_ptr<Physics::ShapeConfiguration> CloneCurrent() const;
 
+    private:
         bool ShowingSubdivisionLevel() const;
-
+        AZ::u32 OnShapeTypeChanged();
         AZ::u32 OnConfigurationChanged();
+
+        Physics::ShapeType m_lastShapeType = Physics::ShapeType::PhysicsAsset;
     };
 
     class EditorColliderComponentDescriptor;