Added GenerateMask to AssetsHelpers;

Editor/AssetsHelpers/Implementation/Material/CreateTerrainLayer/CreateTerrainLayerProcessor.cs

@@ -0,0 +1,37 @@
+using System.IO;
+using UnityEditor;
+using UnityEngine;
+
+namespace Misaki.ArtToolEditor
+{
+    internal class CreateTerrainLayerProcessor : IAssetsProcessor
+    {
+        private const string Terrain_Layer_Extension = ".terrainlayer";
+
+        public void OnPreProcess(AssetsProcessContext context)
+        {
+        }
+
+        public void OnProcess(UnityEngine.Object source, string outputDirectory, AssetsProcessContext context)
+        {
+            if (source is not Material mat)
+            {
+                return;
+            }
+
+            var terrainLayer = new TerrainLayer()
+            {
+                diffuseTexture = mat.GetTexture("_BaseColorMap") as Texture2D,
+                normalMapTexture = mat.GetTexture("_NormalMap") as Texture2D,
+                maskMapTexture = mat.GetTexture("_MaskMap") as Texture2D,
+            };
+
+            var outputPath = Path.Combine(outputDirectory, mat.name + Terrain_Layer_Extension);
+            AssetDatabase.CreateAsset(terrainLayer, outputPath);
+        }
+
+        public void OnPostProcess(AssetsProcessContext context)
+        {
+        }
+    }
+}