[unity] Fixed removing unreferenced SlotBlendMode material entries, closes #1249.

spine-unity/Assets/Spine/Runtime/spine-unity/Modules/SlotBlendModes/SlotBlendModes.cs

@@ -42,28 +42,70 @@ namespace Spine.Unity.Modules {
 			public Material material;
 		}
 
-		static Dictionary<MaterialTexturePair, Material> materialTable;
-		internal static Dictionary<MaterialTexturePair, Material> MaterialTable {
+		internal class MaterialWithRefcount {
+			public Material materialClone;
+			public int refcount = 1;
+
+			public MaterialWithRefcount(Material mat) {
+				this.materialClone = mat;
+			}
+		}
+		static Dictionary<MaterialTexturePair, MaterialWithRefcount> materialTable;
+		internal static Dictionary<MaterialTexturePair, MaterialWithRefcount> MaterialTable {
 			get {
-				if (materialTable == null) materialTable = new Dictionary<MaterialTexturePair, Material>();
+				if (materialTable == null) materialTable = new Dictionary<MaterialTexturePair, MaterialWithRefcount>();
 				return materialTable;
 			}
 		}
 
-		internal static Material GetMaterialFor (Material materialSource, Texture2D texture) {
+		internal struct SlotMaterialTextureTuple {
+			public Slot slot;
+			public Texture2D texture2D;
+			public Material material;
+
+			public SlotMaterialTextureTuple(Slot slot, Material material, Texture2D texture) {
+				this.slot = slot;
+				this.material = material;
+				this.texture2D = texture;
+			}
+		}
+		
+		internal static Material GetOrAddMaterialFor(Material materialSource, Texture2D texture) {
 			if (materialSource == null || texture == null) return null;
 
 			var mt = SlotBlendModes.MaterialTable;
-			Material m;
+			MaterialWithRefcount matWithRefcount;
 			var key = new MaterialTexturePair {	material = materialSource, texture2D = texture };
-			if (!mt.TryGetValue(key, out m)) {
-				m = new Material(materialSource);
+			if (!mt.TryGetValue(key, out matWithRefcount)) {
+				matWithRefcount = new MaterialWithRefcount(new Material(materialSource));
+				var m = matWithRefcount.materialClone;
 				m.name = "(Clone)" + texture.name + "-" + materialSource.name;
 				m.mainTexture = texture;
-				mt[key] = m;
+				mt[key] = matWithRefcount;
 			}
+			else {
+				matWithRefcount.refcount++;
+			}
+			return matWithRefcount.materialClone;
+		}
 
-			return m;
+		internal static MaterialWithRefcount GetExistingMaterialFor(Material materialSource, Texture2D texture)
+		{
+			if (materialSource == null || texture == null) return null;
+
+			var mt = SlotBlendModes.MaterialTable;
+			MaterialWithRefcount matWithRefcount;
+			var key = new MaterialTexturePair { material = materialSource, texture2D = texture };
+			if (!mt.TryGetValue(key, out matWithRefcount)) {
+				return null;
+			}
+			return matWithRefcount;
+		}
+
+		internal static void RemoveMaterialFromTable(Material materialSource, Texture2D texture) {
+			var mt = SlotBlendModes.MaterialTable;
+			var key = new MaterialTexturePair { material = materialSource, texture2D = texture };
+			mt.Remove(key);
 		}
 		#endregion
 
@@ -74,17 +116,19 @@ namespace Spine.Unity.Modules {
 		Texture2D texture;
 		#endregion
 
+		SlotMaterialTextureTuple[] slotsWithCustomMaterial = new SlotMaterialTextureTuple[0];
+
 		public bool Applied { get; private set; }
 
-		void Start () {
+		void Start() {
 			if (!Applied) Apply();
 		}
 
-		void OnDestroy () {
+		void OnDestroy() {
 			if (Applied) Remove();
 		}
 
-		public void Apply () {
+		public void Apply() {
 			GetTexture();
 			if (texture == null) return;
 
@@ -93,13 +137,36 @@ namespace Spine.Unity.Modules {
 
 			var slotMaterials = skeletonRenderer.CustomSlotMaterials;
 
+			int numSlotsWithCustomMaterial = 0;
 			foreach (var s in skeletonRenderer.Skeleton.Slots) {
 				switch (s.data.blendMode) {
 				case BlendMode.Multiply:
-					if (multiplyMaterialSource != null) slotMaterials[s] = GetMaterialFor(multiplyMaterialSource, texture);
+					if (multiplyMaterialSource != null) {
+						slotMaterials[s] = GetOrAddMaterialFor(multiplyMaterialSource, texture);
+						++numSlotsWithCustomMaterial;
+					}
 					break;
 				case BlendMode.Screen:
-					if (screenMaterialSource != null) slotMaterials[s] = GetMaterialFor(screenMaterialSource, texture);
+					if (screenMaterialSource != null) {
+						slotMaterials[s] = GetOrAddMaterialFor(screenMaterialSource, texture);
+						++numSlotsWithCustomMaterial;
+					}
+					break;
+				}
+			}
+			slotsWithCustomMaterial = new SlotMaterialTextureTuple[numSlotsWithCustomMaterial];
+			int storedSlotIndex = 0;
+			foreach (var s in skeletonRenderer.Skeleton.Slots) {
+				switch (s.data.blendMode) {
+				case BlendMode.Multiply:
+					if (multiplyMaterialSource != null) {
+						slotsWithCustomMaterial[storedSlotIndex++] = new SlotMaterialTextureTuple(s, multiplyMaterialSource, texture);
+					}
+					break;
+				case BlendMode.Screen:
+					if (screenMaterialSource != null) {
+						slotsWithCustomMaterial[storedSlotIndex++] = new SlotMaterialTextureTuple(s, screenMaterialSource, texture);
+					}
 					break;
 				}
 			}
@@ -108,7 +175,7 @@ namespace Spine.Unity.Modules {
 			skeletonRenderer.LateUpdate();
 		}
 
-		public void Remove () {
+		public void Remove() {
 			GetTexture();
 			if (texture == null) return;
 
@@ -117,26 +184,32 @@ namespace Spine.Unity.Modules {
 
 			var slotMaterials = skeletonRenderer.CustomSlotMaterials;
 
-			foreach (var s in skeletonRenderer.Skeleton.Slots) {
-				Material m = null;
+			foreach (var slotWithCustomMat in slotsWithCustomMaterial) {
 
-				switch (s.data.blendMode) {
-				case BlendMode.Multiply:
-					if (slotMaterials.TryGetValue(s, out m) && Material.ReferenceEquals(m, GetMaterialFor(multiplyMaterialSource, texture)))
-						slotMaterials.Remove(s);
-					break;
-				case BlendMode.Screen:
-					if (slotMaterials.TryGetValue(s, out m) && Material.ReferenceEquals(m, GetMaterialFor(screenMaterialSource, texture)))
+				Slot s = slotWithCustomMat.slot;
+				Material storedMaterialSource = slotWithCustomMat.material;
+				Texture2D storedTexture = slotWithCustomMat.texture2D;
+
+				var matWithRefcount = GetExistingMaterialFor(storedMaterialSource, storedTexture);
+				if (--matWithRefcount.refcount == 0) {
+					RemoveMaterialFromTable(storedMaterialSource, storedTexture);
+				}
+				// we don't want to remove slotMaterials[s] if it has been changed in the meantime.
+				Material m;
+				if (slotMaterials.TryGetValue(s, out m)) {
+					var existingMat = matWithRefcount == null ? null : matWithRefcount.materialClone;
+					if (Material.ReferenceEquals(m, existingMat)) {
 						slotMaterials.Remove(s);
-					break;
+					}
 				}
 			}
-
+			slotsWithCustomMaterial = null;
+			
 			Applied = false;
 			if (skeletonRenderer.valid) skeletonRenderer.LateUpdate();
 		}
 
-		public void GetTexture () {
+		public void GetTexture() {
 			if (texture == null) {
 				var sr = GetComponent<SkeletonRenderer>(); if (sr == null) return;
 				var sda = sr.skeletonDataAsset; if (sda == null) return;
@@ -146,7 +219,6 @@ namespace Spine.Unity.Modules {
 			}
 		}
 
-
 	}
 }