Texture ASTC轉換ETC

傳統方式修改是通過TextureImporter的方法，先把Texture加載出來再修改，但是這樣的話很浪費時間；我的方法是直接修改Texture的.meta文件，速度比之前的快一倍。

[MenuItem("Assets/設置文件夾以及子文件夾下面的圖片壓縮格式爲ETC", priority = 0)]
    static void AutoSetASTC()
    {
        Debug.Log("開始");
        string[] guid = Selection.assetGUIDs;
        List<string> lstPath = new List<string>();
        for (int i = 0; i < guid.Length; i++)
        {
            string dirPath = AssetDatabase.GUIDToAssetPath(guid[i]);
            lstPath.Add(dirPath);
        }

        string[] textures = AssetDatabase.FindAssets("t:Texture", lstPath.ToArray());
        for (int i = 0; i < textures.Length; i++)
        {
            EditorUtility.DisplayProgressBar("Texture", i + "/" + textures.Length, (float)i / textures.Length);

            //修改Meta文件
            bool bModify = false;
            string texPath = AssetDatabase.GUIDToAssetPath(textures[i]);
            TextureImporter texImporter = AssetImporter.GetAtPath(texPath) as TextureImporter;
            string metaPath = texPath + ".meta";
            List<string> metaContent = new List<string>();
            using (StreamReader sr = new StreamReader(metaPath))
            {
                bool bAndroid = false;
                while (!sr.EndOfStream)
                {
                    string line = sr.ReadLine();
                    bAndroid = line.Contains("buildTarget") ? (line.Contains("Android") ? true : false) : bAndroid;

                    if (bAndroid && line.IndexOf("textureFormat:") != -1)
                    {
                        string[] textureMetas = line.Split(':');
                        if (textureMetas.Length == 2)
                        {
                            int texFormat = int.Parse(textureMetas[1]);
                            if (texFormat >= (int)TextureImporterFormat.ASTC_RGB_4x4 && texFormat <= (int)TextureImporterFormat.ASTC_RGB_12x12)
                            {
                                bModify = true;
                                texFormat = (int)TextureImporterFormat.ETC2_RGB4;
                                line = string.Format("{0}: {1}", textureMetas[0], texFormat.ToString());
                            }
                            else if (texFormat >= (int)TextureImporterFormat.ASTC_RGBA_4x4 && texFormat <= (int)TextureImporterFormat.ASTC_RGBA_12x12)
                            {
                                bModify = true;
                                texFormat = (int)TextureImporterFormat.ETC2_RGBA8;
                                line = string.Format("{0}: {1}", textureMetas[0], texFormat.ToString());
                            }
                        }
                    }

                    if (bAndroid && line.IndexOf("overridden:") != -1)
                    {
                        string[] textureMetas = line.Split(':');
                        if (textureMetas.Length == 2)
                        {
                            int texFormat = int.Parse(textureMetas[1]);
                            if (bModify)
                                bModify = texFormat == 1 ? true : false;
                        }
                    }

                    metaContent.Add(line);
                }
                sr.Close();
            }

            if (bModify)
            {
                File.Delete(metaPath);
                using (StreamWriter sw = new StreamWriter(metaPath))
                {
                    foreach (string line in metaContent)
                    {
                        sw.WriteLine(line);
                    }
                    sw.Close();
                }
            }
            metaContent.Clear();

            //對Texture進行修改
            //int maxTexSize;
            //int compressionQuality;
            //TextureImporterFormat texFormat;
            //string texPath = AssetDatabase.GUIDToAssetPath(textures[i]);
            //TextureImporter texImporter = AssetImporter.GetAtPath(texPath) as TextureImporter;
            //TextureImporterPlatformSettings settingPlatform = texImporter.GetPlatformTextureSettings("Android");

            //if (texImporter.GetPlatformTextureSettings("Android", out maxTexSize, out texFormat, out compressionQuality))
            //{
            //    //texFormat = texImporter.DoesSourceTextureHaveAlpha() ? (texFormat != TextureImporterFormat.ETC2_RGBA8 ? TextureImporterFormat.ETC2_RGBA8 : texFormat)
            //    //    : (texFormat != TextureImporterFormat.ETC2_RGB4 ? TextureImporterFormat.ETC2_RGB4 : texFormat);
            //    //settingPlatform.format = texFormat;

            //    texFormat = texImporter.DoesSourceTextureHaveAlpha() ? (texFormat != TextureImporterFormat.ASTC_RGBA_8x8 ? TextureImporterFormat.ASTC_RGBA_8x8 : texFormat)
            //            : (texFormat != TextureImporterFormat.ASTC_RGB_8x8 ? TextureImporterFormat.ASTC_RGB_8x8 : texFormat);
            //    settingPlatform.format = texFormat;
            //}
            //texImporter.SetPlatformTextureSettings(settingPlatform);
            //texImporter.SaveAndReimport();
        }
        AssetDatabase.Refresh();
        Debug.Log("End");

        EditorUtility.ClearProgressBar();
    }

 

直接拷貝就能用。