Add metallic gloss to decals

1 files changed, 113 insertions, 0 deletions

diff --git a/Scripts/Editor/MetallicGloss.cs b/Scripts/Editor/MetallicGloss.cs
new file mode 100644
index 0000000..d0b8895
--- /dev/null
+++ b/Scripts/Editor/MetallicGloss.cs
@@ -0,0 +1,113 @@
+using System.IO;
+using UnityEditor;
+using UnityEngine;
+
+public class MetallicGloss : EditorWindow
+{
+    Texture2D metallicMap;
+    Texture2D smoothnessMap;
+    bool invertMetallic;
+    bool invertSmoothness;
+
+    [MenuItem("Tools/yum_food/Metallic Gloss")]
+    static void ShowWindow()
+    {
+        var window = GetWindow<MetallicGloss>("Metallic Gloss");
+        window.minSize = new Vector2(300, 180);
+    }
+
+    void OnGUI()
+    {
+        EditorGUILayout.Space(5);
+
+        metallicMap = (Texture2D)EditorGUILayout.ObjectField("Metallic Map", metallicMap, typeof(Texture2D), false);
+        invertMetallic = EditorGUILayout.Toggle("Invert", invertMetallic);
+
+        EditorGUILayout.Space(5);
+
+        smoothnessMap = (Texture2D)EditorGUILayout.ObjectField("Smoothness Map", smoothnessMap, typeof(Texture2D), false);
+        invertSmoothness = EditorGUILayout.Toggle("Invert", invertSmoothness);
+
+        if (metallicMap != null) EnforceLinear(metallicMap);
+        if (smoothnessMap != null) EnforceLinear(smoothnessMap);
+
+        EditorGUILayout.Space(10);
+
+        using (new EditorGUI.DisabledScope(metallicMap == null && smoothnessMap == null))
+        {
+            if (GUILayout.Button("Merge"))
+                Merge();
+        }
+    }
+
+    static void EnforceLinear(Texture2D tex)
+    {
+        string path = AssetDatabase.GetAssetPath(tex);
+        if (!string.IsNullOrEmpty(path)) EnforceSettings(path);
+    }
+
+    static void EnforceSettings(string path)
+    {
+        var importer = AssetImporter.GetAtPath(path) as TextureImporter;
+        if (importer == null) return;
+        bool dirty = false;
+        if (importer.sRGBTexture) { importer.sRGBTexture = false; dirty = true; }
+        if (importer.textureType != TextureImporterType.Default) { importer.textureType = TextureImporterType.Default; dirty = true; }
+        if (importer.wrapMode != TextureWrapMode.Repeat) { importer.wrapMode = TextureWrapMode.Repeat; dirty = true; }
+        if (importer.filterMode != FilterMode.Trilinear) { importer.filterMode = FilterMode.Trilinear; dirty = true; }
+        if (importer.anisoLevel != 4) { importer.anisoLevel = 4; dirty = true; }
+        if (dirty) importer.SaveAndReimport();
+    }
+
+    void Merge()
+    {
+        Texture2D reference = metallicMap != null ? metallicMap : smoothnessMap;
+        int w = reference.width;
+        int h = reference.height;
+
+        Color[] mPixels = metallicMap != null ? ReadPixels(metallicMap, w, h) : null;
+        Color[] sPixels = smoothnessMap != null ? ReadPixels(smoothnessMap, w, h) : null;
+
+        var pixels = new Color[w * h];
+        for (int i = 0; i < pixels.Length; i++)
+        {
+            float m = mPixels != null ? mPixels[i].r : 0;
+            float s = sPixels != null ? sPixels[i].r : 0;
+            if (invertMetallic) m = 1 - m;
+            if (invertSmoothness) s = 1 - s;
+            pixels[i] = new Color(m, 0, 0, s);
+        }
+
+        var output = new Texture2D(w, h, TextureFormat.RGBA32, false, true);
+        output.SetPixels(pixels);
+        output.Apply();
+
+        string refPath = AssetDatabase.GetAssetPath(reference);
+        string dir = Path.GetDirectoryName(refPath);
+        string basename = Path.GetFileNameWithoutExtension(refPath);
+        string outputPath = Path.Combine(dir, basename + "_metallic_gloss.png");
+
+        File.WriteAllBytes(outputPath, output.EncodeToPNG());
+        DestroyImmediate(output);
+        AssetDatabase.ImportAsset(outputPath);
+
+        EnforceSettings(outputPath);
+        EditorGUIUtility.PingObject(AssetDatabase.LoadAssetAtPath<Texture2D>(outputPath));
+    }
+
+    static Color[] ReadPixels(Texture2D tex, int w, int h)
+    {
+        var rt = RenderTexture.GetTemporary(w, h, 0, RenderTextureFormat.ARGB32, RenderTextureReadWrite.Linear);
+        Graphics.Blit(tex, rt);
+        var prev = RenderTexture.active;
+        RenderTexture.active = rt;
+        var tmp = new Texture2D(w, h, TextureFormat.RGBA32, false, true);
+        tmp.ReadPixels(new Rect(0, 0, w, h), 0, 0);
+        tmp.Apply();
+        RenderTexture.active = prev;
+        RenderTexture.ReleaseTemporary(rt);
+        var pixels = tmp.GetPixels();
+        DestroyImmediate(tmp);
+        return pixels;
+    }
+}