Fix venues shaders on OSX (again)

Previously we were exporting shaders for OSX separately.
Unfortunately that does not seem to guarantee that all shader variants were exported.
To mitigate that we now export materials as well. However to avoid
doubling of resulting yarground size we replace all textures with dummy on export.

Loading side does not change

Assets/Script/Gameplay/BackgroundManager.cs

@@ -91,7 +91,7 @@ private async UniTaskVoid Start()
                     // Yarground comes with shaders for dx11/dx12/glcore/vulkan
                     // Metal shaders used on OSX come in this separate bundle
                     // Update our renderers to use them
-                    var renderers = bg.GetComponentsInChildren<Renderer>();
+                    var renderers = bg.GetComponentsInChildren<Renderer>(true);
 
                     foreach (var renderer in renderers)
                     {

Assets/Script/Venue/BundleBackgroundManager.cs

@@ -15,6 +15,7 @@ public class BundleBackgroundManager : MonoBehaviour
         // DO NOT CHANGE THIS! It will break existing venues
         public const string BACKGROUND_PREFAB_PATH = "Assets/_Background.prefab";
         public const string BACKGROUND_SHADER_BUNDLE_NAME = "_metal_shaders.bytes";
+        public const string BACKGOUND_OSX_MATERIAL_PREFIX = "_metal_";
 
         // DO NOT CHANGE the name of this! I *know* it doesn't follow naming conventions, but it will also break existing
         // venues if we do change it.
@@ -58,11 +59,9 @@ public void ExportBackground()
             _backgroundReference = gameObject;
             string path = EditorUtility.SaveFilePanel("Save Background", string.Empty, "bg", "yarground");
 
-            var selectedBuildTargetGroup = EditorUserBuildSettings.selectedBuildTargetGroup;
-            var activeBuildTarget = EditorUserBuildSettings.activeBuildTarget;
-
             GameObject clonedBackground = null;
 
+            AssetDatabase.DisallowAutoRefresh();
 
             try
             {
@@ -74,17 +73,45 @@ public void ExportBackground()
                 // First we'll collect all shaders and build a separate bundle out of them
                 // for Mac as no other build target will include Metal shaders
                 // And we want our background to work everywhere
-                var shaderAssets = EditorUtility.CollectDependencies(new[] { gameObject })
-                    .OfType<Shader>() // Only shader dependencices
-                    .Select(shader => AssetDatabase.GetAssetPath(shader)) // Get asset path
-                    .Where(assetPath => !assetPath.StartsWith("Packages/com.unity")) // Not builtins
+
+                // We use materials as "anchors" to make sure all required
+                // shader variants are included
+                // var materialAssets = EditorUtility.CollectDependencies(new[] { gameObject })
+                var materialAssets = EditorUtility.CollectDependencies(new[] { gameObject })
+                    .OfType<Material>() // Only material dependencices
+                    .Select((mat, i) =>
+                    {
+                        // Create a clone
+                        var matClone = new Material(mat);
+                        // Avoid name collision
+                        matClone.name = BACKGOUND_OSX_MATERIAL_PREFIX + mat.name;
+                        // Drop all textures to not double resulting yarground in size
+                        if (matClone.mainTexture != null)
+                        {
+                            matClone.mainTexture = Texture2D.whiteTexture;
+                        }
+                        foreach (var id in matClone.GetTexturePropertyNameIDs())
+                        {
+                            if (matClone.GetTexture(id) != null)
+                            {
+                                matClone.SetTexture(id, Texture2D.whiteTexture);
+                            }
+                        }
+                        var assetPath = Path.Combine("Assets", matClone.name + ".mat");
+                        AssetDatabase.CreateAsset(matClone, assetPath);
+
+                        return assetPath;
+                    })
                     .ToArray();
 
-                if (shaderAssets.Length > 0)
+                var shaderAssets = EditorUtility.CollectDependencies(new[] { gameObject })
+                    .OfType<Shader>().Select(AssetDatabase.GetAssetPath);
+
+                if (materialAssets.Length > 0)
                 {
                     var metalAssetBundleBuild = default(AssetBundleBuild);
                     metalAssetBundleBuild.assetBundleName = BACKGROUND_SHADER_BUNDLE_NAME;
-                    metalAssetBundleBuild.assetNames = shaderAssets;
+                    metalAssetBundleBuild.assetNames = materialAssets.Concat(shaderAssets).ToArray();
 
                     BuildPipeline.BuildAssetBundles(Application.temporaryCachePath,
                         new[]
@@ -94,8 +121,14 @@ public void ExportBackground()
                         BuildTarget.StandaloneOSX);
 
                     var filePath = Path.Combine(Application.temporaryCachePath, BACKGROUND_SHADER_BUNDLE_NAME);
-                    File.Move(filePath, Path.Combine(Application.dataPath, BACKGROUND_SHADER_BUNDLE_NAME));
-                    AssetDatabase.Refresh();
+                    var assetPath = Path.Combine(Application.dataPath, BACKGROUND_SHADER_BUNDLE_NAME);
+                    File.Move(filePath, assetPath);
+                    AssetDatabase.ImportAsset(assetPath);
+                }
+                // Now delete our material clones
+                foreach (var assetPath in materialAssets)
+                {
+                    AssetDatabase.DeleteAsset(assetPath);
                 }
 
                 clonedBackground = Instantiate(_backgroundReference.gameObject);
@@ -144,6 +177,7 @@ public void ExportBackground()
             }
             finally
             {
+                AssetDatabase.AllowAutoRefresh();
                 if (clonedBackground != null)
                 {
                     DestroyImmediate(clonedBackground);