Made material property auto-rename procedure apply to Material Component at runtime. This ensures that an material property overrides and any gameplay scripts that work with property overrides can get the benefit of the material type version update procedure.

I added an ApplyPropertyRenames function to MaterialTypeAsset very similar to the one in MaterialTypeSourceData.
Updated the MaterialAssignment class to apply any property renames when it discovers the old name doesn't work. This will be written to disk when the level or prefab is saved.

Signed-off-by: santorac <55155825+santorac@users.noreply.github.com>

AutomatedTesting/Materials/MinimalBlue.material

@@ -0,0 +1,17 @@
+{
+    "description": "",
+    "parentMaterial": "",
+    "materialType": "TestData/Materials/Types/MinimalPBR.materialtype",
+    "materialTypeVersion": 3,
+    "properties": {
+        "settings": {
+            "color": [
+                0.08522164076566696,
+                0.11898985505104065,
+                1.0,
+                1.0
+            ],
+            "roughness": 0.33000001311302185
+        }
+    }
+}

Gems/Atom/Feature/Common/Code/Source/Material/MaterialAssignment.cpp

@@ -137,11 +137,33 @@ namespace AZ
 
             if (m_materialInstance->CanCompile())
             {
+                AZStd::vector<AZStd::pair<Name, Name>> renamedProperties;
+
                 for (const auto& propertyPair : m_propertyOverrides)
                 {
                     if (!propertyPair.second.empty())
                     {
-                        const auto& materialPropertyIndex = m_materialInstance->FindPropertyIndex(propertyPair.first);
+                        RPI::MaterialPropertyIndex materialPropertyIndex = m_materialInstance->FindPropertyIndex(propertyPair.first);
+
+                        // If we didn't find the name, check to see if there was a rename that should be used.
+                        if (materialPropertyIndex.IsNull())
+                        {
+                            Name propertyId = propertyPair.first;
+
+                            if (m_materialInstance->GetAsset()->GetMaterialTypeAsset()->ApplyPropertyRenames(propertyId))
+                            {
+                                renamedProperties.emplace_back(propertyPair.first, propertyId);
+                                
+                                // We should be able to find the property now, using the new name
+                                materialPropertyIndex = m_materialInstance->FindPropertyIndex(propertyId);
+
+                                AZ_Warning("MaterialAssignment", false,
+                                    "Material property '%s' has been renamed to '%s', and a material override references the old name. Save the level or prefab to permanently apply this change.",
+                                    propertyPair.first.GetCStr(),
+                                    propertyId.GetCStr());
+                            }
+                        }
+
                         if (!materialPropertyIndex.IsNull())
                         {
                             m_materialInstance->SetPropertyValue(
@@ -150,6 +172,15 @@ namespace AZ
                     }
                 }
 
+                // Now that we're done looping over all the overrides, it's safe to apply any renames that were scheduled
+                for (auto& pair : renamedProperties)
+                {
+                    const Name& oldName = pair.first;
+                    const Name& newName = pair.second;
+                    m_propertyOverrides[newName] = m_propertyOverrides[oldName];
+                    m_propertyOverrides.erase(oldName);
+                }
+
                 return m_materialInstance->Compile();
             }
 

Gems/Atom/RPI/Code/Include/Atom/RPI.Reflect/Material/MaterialTypeAsset.h

@@ -129,6 +129,10 @@ namespace AZ
  
             const AZStd::vector<MaterialVersionUpdate>& GetMaterialVersionUpdateList() const { return m_materialVersionUpdates; }
 
+            //! Possibly renames @propertyId based on the material version update steps.
+            //! @return true if the property was renamed
+            bool ApplyPropertyRenames(AZ::Name& propertyId) const;
+
         private:
             bool PostLoadInit() override;
 

Gems/Atom/RPI/Code/Include/Atom/RPI.Reflect/Material/MaterialVersionUpdate.h

@@ -45,6 +45,10 @@ namespace AZ
             uint32_t GetVersion() const;
             void SetVersion(uint32_t toVersion);
             
+            //! Possibly renames @propertyId based on the material version update steps.
+            //! @return true if the property was renamed
+            bool ApplyPropertyRenames(AZ::Name& propertyId) const;
+
             //! Apply version updates to the given material asset.
             //! @return true if any changes were made
             bool ApplyVersionUpdates(MaterialAsset& materialAsset) const;

Gems/Atom/RPI/Code/Source/RPI.Reflect/Material/MaterialTypeAsset.cpp

@@ -169,6 +169,22 @@ namespace AZ
             return m_version;
         }
 
+
+        bool MaterialTypeAsset::ApplyPropertyRenames(AZ::Name& propertyId) const
+        {
+            bool renamed = false;
+
+            for (const auto& versionUpdates : m_materialVersionUpdates)
+            {
+                if (versionUpdates.ApplyPropertyRenames(propertyId))
+                {
+                    renamed = true;
+                }
+            }
+
+            return renamed;
+        }
+
         void MaterialTypeAsset::SetReady()
         {
             m_status = AssetStatus::Ready;

Gems/Atom/RPI/Code/Source/RPI.Reflect/Material/MaterialVersionUpdate.cpp

@@ -57,6 +57,22 @@ namespace AZ
             m_toVersion = toVersion;
         }
         
+        bool MaterialVersionUpdate::ApplyPropertyRenames(AZ::Name& propertyId) const
+        {
+            bool renamed = false;
+
+            for (const auto& action : m_actions)
+            {
+                if (action.m_fromPropertyId == propertyId)
+                {
+                    propertyId = action.m_toPropertyId;
+                    renamed = true;
+                }
+            }
+
+            return renamed;
+        }
+
         bool MaterialVersionUpdate::ApplyVersionUpdates(MaterialAsset& materialAsset) const
         {
             bool changesWereApplied = false;

Gems/Atom/RPI/Code/Tests/Material/MaterialTypeAssetTests.cpp

@@ -1041,5 +1041,88 @@ namespace UnitTest
         EXPECT_FALSE(materialTypeAsset->GetShaderCollection()[1].MaterialOwnsShaderOption(Name{"o_globalOption_inShaderB"}));
     }
 
+    TEST_F(MaterialTypeAssetTests, ApplyPropertyRenames)
+    {
+        Data::Asset<MaterialTypeAsset> materialTypeAsset;
+
+        auto addRenameAction = [](MaterialVersionUpdate& versionUpdate, const char* from, const char* to)
+        {
+            versionUpdate.AddAction(MaterialVersionUpdate::RenamePropertyAction(
+                {
+                    Name{ from },
+                    Name{ to }
+                }));
+        };
+
+        MaterialTypeAssetCreator materialTypeCreator;
+        materialTypeCreator.Begin(Uuid::CreateRandom());
+
+        // Version updates
+        materialTypeCreator.SetVersion(10);
+
+        MaterialVersionUpdate versionUpdate2(2);
+        addRenameAction(versionUpdate2, "general.fooA", "general.fooB");
+        materialTypeCreator.AddVersionUpdate(versionUpdate2);
+
+        MaterialVersionUpdate versionUpdate4(4);
+        addRenameAction(versionUpdate4, "general.barA", "general.barB");
+        materialTypeCreator.AddVersionUpdate(versionUpdate4);
+
+        MaterialVersionUpdate versionUpdate6(6);
+        addRenameAction(versionUpdate6, "general.fooB", "general.fooC");
+        addRenameAction(versionUpdate6, "general.barB", "general.barC");
+        materialTypeCreator.AddVersionUpdate(versionUpdate6);
+
+        MaterialVersionUpdate versionUpdate7(7);
+        addRenameAction(versionUpdate7, "general.bazA", "otherGroup.bazB");
+        materialTypeCreator.AddVersionUpdate(versionUpdate7);
+        
+        materialTypeCreator.BeginMaterialProperty(Name{ "general.fooC" }, MaterialPropertyDataType::Bool);
+        materialTypeCreator.EndMaterialProperty();
+        materialTypeCreator.BeginMaterialProperty(Name{ "general.barC" }, MaterialPropertyDataType::Bool);
+        materialTypeCreator.EndMaterialProperty();
+        materialTypeCreator.BeginMaterialProperty(Name{ "otherGroup.bazB" }, MaterialPropertyDataType::Bool);
+        materialTypeCreator.EndMaterialProperty();
+
+        EXPECT_TRUE(materialTypeCreator.End(materialTypeAsset));
+
+        AZ::Name propertyId;
+
+        propertyId = AZ::Name{"doesNotExist"};
+        EXPECT_FALSE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "doesNotExist");
+
+        propertyId = AZ::Name{"general.fooA"};
+        EXPECT_TRUE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.fooC");
+
+        propertyId = AZ::Name{"general.fooB"};
+        EXPECT_TRUE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.fooC");
+
+        propertyId = AZ::Name{"general.fooC"};
+        EXPECT_FALSE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.fooC");
+
+        propertyId = AZ::Name{"general.barA"};
+        EXPECT_TRUE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.barC");
+
+        propertyId = AZ::Name{"general.barB"};
+        EXPECT_TRUE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.barC");
+
+        propertyId = AZ::Name{"general.barC"};
+        EXPECT_FALSE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "general.barC");
+
+        propertyId = AZ::Name{"general.bazA"};
+        EXPECT_TRUE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "otherGroup.bazB");
+
+        propertyId = AZ::Name{"otherGroup.bazB"};
+        EXPECT_FALSE(materialTypeAsset->ApplyPropertyRenames(propertyId));
+        EXPECT_STREQ(propertyId.GetCStr(), "otherGroup.bazB");
+    }
 }