From 10497fe92c89486dd8ccd0a391aef624ed5abac3 Mon Sep 17 00:00:00 2001
From: Sergey Pereslavtsev <pereslav@amazon.com>
Date: Mon, 10 Jan 2022 20:43:33 +0000
Subject: [PATCH 1/2] LYN-9183 Fix Terrain Heightfield Collider component to
 list physics materials from the library

Signed-off-by: Sergey Pereslavtsev <pereslav@amazon.com>
---
 .../TerrainPhysicsColliderComponent.cpp           | 15 +++++++++++++++
 .../Components/TerrainPhysicsColliderComponent.h  |  1 +
 2 files changed, 16 insertions(+)

diff --git a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
index 8c2c0e80b6..916dd800e2 100644
--- a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
+++ b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
@@ -17,6 +17,7 @@
 #include <AzCore/Serialization/SerializeContext.h>
 
 #include <AzFramework/Physics/Material.h>
+#include <AzFramework/Physics/PhysicsSystem.h>
 #include <AzFramework/Terrain/TerrainDataRequestBus.h>
 
 namespace Terrain
@@ -43,11 +44,25 @@ namespace Terrain
                         AZ::Edit::UIHandlers::ComboBox, &TerrainPhysicsSurfaceMaterialMapping::m_surfaceTag, "Surface Tag",
                         "Surface type to map to a physics material.")
                     ->DataElement(AZ::Edit::UIHandlers::Default, &TerrainPhysicsSurfaceMaterialMapping::m_materialId, "Material ID", "")
+                    ->ElementAttribute(Physics::Attributes::MaterialLibraryAssetId, &TerrainPhysicsSurfaceMaterialMapping::GetMaterialLibraryId)
                     ->Attribute(AZ::Edit::Attributes::AutoExpand, true)
                     ->Attribute(AZ::Edit::Attributes::ShowProductAssetFileName, true);
             }
         }
     }
+
+    AZ::Data::AssetId TerrainPhysicsSurfaceMaterialMapping::GetMaterialLibraryId()
+    {
+        if (auto* physicsSystem = AZ::Interface<AzPhysics::SystemInterface>::Get())
+        {
+            if (const auto* physicsConfiguration = physicsSystem->GetConfiguration())
+            {
+                return physicsConfiguration->m_materialLibraryAsset.GetId();
+            }
+        }
+        return {};
+    }
+
     void TerrainPhysicsColliderConfig::Reflect(AZ::ReflectContext* context)
     {
         TerrainPhysicsSurfaceMaterialMapping::Reflect(context);
diff --git a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
index 1a7fbf9c72..284bc74d88 100644
--- a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
+++ b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
@@ -33,6 +33,7 @@ namespace Terrain
         AZ_CLASS_ALLOCATOR(TerrainPhysicsSurfaceMaterialMapping, AZ::SystemAllocator, 0);
         AZ_RTTI(TerrainPhysicsSurfaceMaterialMapping, "{A88B5289-DFCD-4564-8395-E2177DFE5B18}");
         static void Reflect(AZ::ReflectContext* context);
+        static AZ::Data::AssetId GetMaterialLibraryId();
 
         SurfaceData::SurfaceTag m_surfaceTag;
         Physics::MaterialId m_materialId;

From 2e577a8b14ddbd4b67ceed5311e8caf509b821df Mon Sep 17 00:00:00 2001
From: Sergey Pereslavtsev <pereslav@amazon.com>
Date: Tue, 11 Jan 2022 12:11:51 +0000
Subject: [PATCH 2/2] PR feedback

Signed-off-by: Sergey Pereslavtsev <pereslav@amazon.com>
---
 .../Source/Components/TerrainPhysicsColliderComponent.cpp     | 2 +-
 .../Code/Source/Components/TerrainPhysicsColliderComponent.h  | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
index 916dd800e2..c51728a5c3 100644
--- a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
+++ b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.cpp
@@ -53,7 +53,7 @@ namespace Terrain
 
     AZ::Data::AssetId TerrainPhysicsSurfaceMaterialMapping::GetMaterialLibraryId()
     {
-        if (auto* physicsSystem = AZ::Interface<AzPhysics::SystemInterface>::Get())
+        if (const auto* physicsSystem = AZ::Interface<AzPhysics::SystemInterface>::Get())
         {
             if (const auto* physicsConfiguration = physicsSystem->GetConfiguration())
             {
diff --git a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
index 284bc74d88..8a70f282d0 100644
--- a/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
+++ b/Gems/Terrain/Code/Source/Components/TerrainPhysicsColliderComponent.h
@@ -33,10 +33,12 @@ namespace Terrain
         AZ_CLASS_ALLOCATOR(TerrainPhysicsSurfaceMaterialMapping, AZ::SystemAllocator, 0);
         AZ_RTTI(TerrainPhysicsSurfaceMaterialMapping, "{A88B5289-DFCD-4564-8395-E2177DFE5B18}");
         static void Reflect(AZ::ReflectContext* context);
-        static AZ::Data::AssetId GetMaterialLibraryId();
 
         SurfaceData::SurfaceTag m_surfaceTag;
         Physics::MaterialId m_materialId;
+
+    private:
+        static AZ::Data::AssetId GetMaterialLibraryId();
     };
 
     class TerrainPhysicsColliderConfig