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原文出处：https://www.jianshu.com/p/2d41e280deb7
阅读前请先了解下
Unity3D 图片纹理格式
Unity游戏开发图片纹理压缩方案
解决的问题？
包体过大
内存占用大
优化性能
-
方案如何实现
- 通过修改NGUI UIAtalsMaker图集打包工具来修改图集平台对应最优格式
Android： 转成两张RGB ETC 4 bits图，一张保存RGB，一张保存Alpha
iOS ：一般情况下转成RGBA PVRTC 4 bits就行，转成两张RGB PVRTC 4 bits图，一张保存RGB，一张保存Alpha精度更高，工具中转成的是两张图
先目睹下
Atlas Maker
UIOptimization: 图集优化选项
Force Square：图集图片方形 长宽相等 2的n次方
尽量图片大小小于等于2048
- RGB+Alpha合并渲染 复制 NGUI\Resources\Shaders\Unlit - Transparent Colored.shader重命名Unlit - Transparent Colored Split.shader
//暴露在Unity编辑器，赋值资源、改动
Properties {
_MainTex ("Base (RGB)", 2D) = "black" {} //RGB
_MaskTex ("Alpha (A)", 2D) = "black" {} //Alpha
}
Pass{
//添加
sampler2D _MaskTex;//与Properties同名贴图属性绑定
//修改
fixed4 frag (v2f IN) : COLOR{
fixed4 texClr = tex2D(_MainTex, IN.texcoord);
texClr.a = tex2D(_MaskTex, IN.texcoord).r; //顶点Alpah值
return texClr * IN.color;
}
}
-
修改UIAtalsMaker.cs
//OnGUI()中添加
GUILayout.BeginHorizontal();
NGUISettings.uiOptimization = EditorGUILayout.Toggle("UIOptimization", NGUISettings.uiOptimization, GUILayout.Width(100f));
GUILayout.Label("Split texture with 2 RGB ETC 4 (and Alpha) Android ,iOS 2 RGB PVRTC4", GUILayout.MinWidth(70f));
GUILayout.EndHorizontal();
//修改实现 static public bool UpdateTexture (UIAtlas atlas, List<SpriteEntry> sprites)
static public bool UpdateTexture (UIAtlas atlas, List<SpriteEntry> sprites)
{
bool bUIOptimization = NGUISettings.uiOptimization;
// Get the texture for the atlas
Texture2D tex = atlas.texture as Texture2D;
string oldPath = (tex != null) ? AssetDatabase.GetAssetPath(tex.GetInstanceID()) : "";
string newPath = NGUIEditorTools.GetSaveableTexturePath(atlas);
// Clear the read-only flag in texture file attributes
if (System.IO.File.Exists(newPath))
{
#if !UNITY_4_1 && !UNITY_4_0 && !UNITY_3_5
if (!AssetDatabase.IsOpenForEdit(newPath))
{
LogUtil.LogError(newPath + " is not editable. Did you forget to do a check out?");
return false;
}
#endif
System.IO.FileAttributes newPathAttrs = System.IO.File.GetAttributes(newPath);
newPathAttrs &= ~System.IO.FileAttributes.ReadOnly;
System.IO.File.SetAttributes(newPath, newPathAttrs);
}
bool newTexture = (tex == null || oldPath != newPath);
if (newTexture)
{
// Create a new texture for the atlas
tex = new Texture2D(1, 1, TextureFormat.ARGB32, false);
}
else
{
// Make the atlas readable so we can save it
tex = NGUIEditorTools.ImportTexture(oldPath, true, false, false, bUIOptimization);
}
// Pack the sprites into this texture
if (PackTextures(tex, sprites))
{
byte[] bytes = tex.EncodeToPNG();
System.IO.File.WriteAllBytes(newPath, bytes);
bytes = null;
// Load the texture we just saved as a Texture2D
AssetDatabase.SaveAssets();
AssetDatabase.Refresh(ImportAssetOptions.ForceSynchronousImport);
tex = NGUIEditorTools.ImportTexture(newPath, false, true, !atlas.premultipliedAlpha);
// Update the atlas texture
if (newTexture)
{
if (tex == null) LogUtil.LogError("Failed to load the created atlas saved as " + newPath);
else atlas.spriteMaterial.mainTexture = tex;
ReleaseSprites(sprites);
AssetDatabase.SaveAssets();
AssetDatabase.Refresh(ImportAssetOptions.ForceSynchronousImport);
}
if (tex != null && atlas.spriteMaterial.shader != null)
{
if (bUIOptimization)
{
TextureProceseser.ProcessUITex(tex);
}
else
{
if (atlas.spriteMaterial.shader.name == "Unlit/Transparent Colored Split")
{
atlas.spriteMaterial.shader = Shader.Find(NGUISettings.atlasPMA ? "Unlit/Premultiplied Colored" : "Unlit/Transparent Colored");
atlas.spriteMaterial.mainTexture = tex;
//Try delete alpha texture
string folderPath = StringUtils.ParseFolderPath(AssetDatabase.GetAssetPath(tex));
string alphaPath = folderPath + "/" + tex.name + "_a.png";
AssetDatabase.DeleteAsset(alphaPath);
AssetDatabase.SaveAssets();
AssetDatabase.Refresh(ImportAssetOptions.ForceSynchronousImport);
}
}
}
return true;
}
else
{
if (!newTexture) NGUIEditorTools.ImportTexture(oldPath, false, true, !atlas.premultipliedAlpha);
//LogUtil.LogError("Operation canceled: The selected sprites can't fit into the atlas.\n" +
// "Keep large sprites outside the atlas (use UITexture), and/or use multiple atlases instead.");
EditorUtility.DisplayDialog("Operation Canceled", "The selected sprites can't fit into the atlas.\n" +
"Keep large sprites outside the atlas (use UITexture), and/or use multiple atlases instead , ask Jubmo for help", "OK");
return false;
}
}
- 修改NGUISettings.cs
添加 uiOptimization
static public bool uiOptimization
{
get { return GetBool("NGUI UIOptimization", true); }
set { SetBool("NGUI UIOptimization", value); }
}
- 修改 NGUIEditorTools.cs
static public Texture2D ImportTexture(string path, bool forInput, bool force, bool alphaTransparency, bool bUIOptimization = false)
{
if (!string.IsNullOrEmpty(path))
{
if (forInput) { if (!MakeTextureReadable(path, force, bUIOptimization)) return null; }
else if (!MakeTextureAnAtlas(path, force, alphaTransparency, bUIOptimization)) return null;
//return AssetDatabase.LoadAssetAtPath(path, typeof(Texture2D)) as Texture2D;
Texture2D tex = AssetDatabase.LoadAssetAtPath(path, typeof(Texture2D)) as Texture2D;
AssetDatabase.Refresh(ImportAssetOptions.ForceSynchronousImport);
return tex;
}
return null;
}
static public bool MakeTextureReadable(string path, bool force, bool bUIOptimization = false)
{
if (string.IsNullOrEmpty(path)) return false;
TextureImporter ti = AssetImporter.GetAtPath(path) as TextureImporter;
if (ti == null) return false;
TextureImporterSettings settings = new TextureImporterSettings();
ti.ReadTextureSettings(settings);
if (force || !settings.readable || settings.npotScale != TextureImporterNPOTScale.None || settings.alphaIsTransparency)
{
settings.readable = true;
if (NGUISettings.trueColorAtlas) settings.textureFormat = TextureImporterFormat.ARGB32;
settings.npotScale = TextureImporterNPOTScale.None;
settings.alphaIsTransparency = false;
ti.SetTextureSettings(settings);
//优化Andriod和iOS,防止有些图集被压缩了，原本的NGUI AtlasMaker无法重新打图集
if (bUIOptimization)
{
ti.SetPlatformTextureSettings("iOS", ti.maxTextureSize, TextureImporterFormat.RGBA32, (int)TextureCompressionQuality.Normal);
ti.SetPlatformTextureSettings("Android", ti.maxTextureSize, TextureImporterFormat.RGBA32, (int)TextureCompressionQuality.Normal);
//AssetDatabase.WriteImportSettingsIfDirty(path);
}
AssetDatabase.ImportAsset(path, ImportAssetOptions.ForceUpdate | ImportAssetOptions.ForceSynchronousImport);
}
return true;
}
static bool MakeTextureAnAtlas (string path, bool force, bool alphaTransparency, bool bUIOptimization = false)
{
if (string.IsNullOrEmpty(path)) return false;
TextureImporter ti = AssetImporter.GetAtPath(path) as TextureImporter;
if (ti == null) return false;
TextureImporterSettings settings = new TextureImporterSettings();
ti.ReadTextureSettings(settings);
if (force ||
settings.readable ||
settings.maxTextureSize < 4096 ||
settings.wrapMode != TextureWrapMode.Clamp ||
settings.npotScale != TextureImporterNPOTScale.ToNearest)
{
settings.readable = false;
settings.maxTextureSize = 4096;
settings.wrapMode = TextureWrapMode.Clamp;
settings.npotScale = TextureImporterNPOTScale.ToNearest;
if (NGUISettings.trueColorAtlas)
{
settings.textureFormat = TextureImporterFormat.ARGB32;
settings.filterMode = FilterMode.Trilinear;
}
settings.aniso = 4;
settings.alphaIsTransparency = alphaTransparency;
// [yqq] 2015-12-8 force disable mipmap for atlas texture
settings.mipmapEnabled = false;
ti.SetTextureSettings(settings);
//优化Andriod和iOS,防止有些图集被压缩了，原本的NGUI AtlasMaker无法重新打图集
if (bUIOptimization)
{
ti.SetPlatformTextureSettings("iOS", ti.maxTextureSize, TextureImporterFormat.RGBA32, (int)TextureCompressionQuality.Normal);
ti.SetPlatformTextureSettings("Android", ti.maxTextureSize, TextureImporterFormat.RGBA32, (int)TextureCompressionQuality.Normal);
//AssetDatabase.WriteImportSettingsIfDirty(path);
}
AssetDatabase.ImportAsset(path, ImportAssetOptions.ForceUpdate | ImportAssetOptions.ForceSynchronousImport);
}
return true;
}
- Editor目录新建 TextureProceseser.cs
- 添加如下方法
public static void ChangeTextureImportSetting(Texture tex, bool readable, int size, TextureImporterFormat format = TextureImporterFormat.RGBA32, TextureImporterType importType = TextureImporterType.Advanced)
{
string path = AssetDatabase.GetAssetPath(tex);
TextureImporter importer = (TextureImporter)TextureImporter.GetAtPath(path);
importer.textureType = importType;
importer.maxTextureSize = size;
importer.textureFormat = format;
importer.isReadable = true;
AssetDatabase.ImportAsset(path, ImportAssetOptions.ForceUpdate);
}
public static void ProcessUITex(Texture2D tex)
{
SliptAlphaChannelForlMobile(tex);
//修改材质
ModifyMaterial(tex);
AssetDatabase.Refresh();
}
private static void SliptAlphaChannelForlMobile(Texture2D tex)
{
// 将贴图的格式设置为RGBA32，获得相应的通道。
TextureProceseser.ChangeTextureImportSetting(tex, true, Mathf.Max(tex.width, tex.height));
TextureImporterFormat destTexFormat = TextureImporterFormat.AutomaticCompressed;
TextureImporterFormat destAndriodTexFormat = (tex.width == tex.height && tex.width % 2 == 0) ? TextureImporterFormat.ETC_RGB4 : TextureImporterFormat.DXT5;
TextureImporterFormat destIOSTexFormat = (tex.width == tex.height && tex.width % 2 == 0) ? TextureImporterFormat.PVRTC_RGB4 : TextureImporterFormat.RGB24;
int maxTexSize = Mathf.Max(tex.width, tex.height);
int width = tex.width;
int height = tex.height;
// 设置目标格式
TextureImporterSettings settings = new TextureImporterSettings();
settings.ApplyTextureType(TextureImporterType.Advanced, true);
settings.mipmapEnabled = false;
settings.npotScale = TextureImporterNPOTScale.ToNearest;
settings.readable = false;
settings.normalMap = false;
settings.lightmap = false;
settings.generateCubemap = TextureImporterGenerateCubemap.None;
settings.wrapMode = TextureWrapMode.Clamp;
settings.textureFormat = destTexFormat;
settings.maxTextureSize = maxTexSize;
settings.filterMode = FilterMode.Bilinear;
settings.alphaIsTransparency = true;
settings.aniso = 4;
// 获取原始像素数据的引用。
Color32[] pixels = tex.GetPixels32();
int pixelCount = pixels.Length;
Color32[] rawPixels = new Color32[pixelCount];
for (int i = 0; i < pixelCount; ++i)
{
rawPixels[i] = new Color32(pixels[i].r, pixels[i].g, pixels[i].b, pixels[i].a);
}
string folderPath = StringUtils.ParseFolderPath(AssetDatabase.GetAssetPath(tex));
string rgbPath = folderPath + "/" + tex.name + ".png";
// 首先生成Alpha通道的贴图。
Texture2D alpha = new Texture2D(tex.width, tex.height, TextureFormat.RGB24, false);
Color32[] alphaPixels = new Color32[pixelCount];
for (int i = 0; i < pixelCount; i++)
{
alphaPixels[i] = new Color32(rawPixels[i].a, rawPixels[i].a, rawPixels[i].a, rawPixels[i].a);
}
alpha.SetPixels32(alphaPixels);
alpha.Apply(false);
string fileName = tex.name + "_a";
string alphaPath = folderPath + "/" + fileName + ".png";
System.IO.File.WriteAllBytes(alphaPath, alpha.EncodeToPNG());
/* 原图还是保留，不复写，至修改平台相关参数
// 转换自己的格式，丢弃Alpha通道并保存。
tex.Resize(width, height, TextureFormat.RGB24, false);
tex.SetPixels32(rawPixels);
tex.Apply(false);
System.IO.File.WriteAllBytes(rgbPath, tex.EncodeToPNG());
*/
AssetDatabase.Refresh();
// 修改纹理的贴图设置
TextureProceseser.ChangeTextureImportSetting(tex, settings);
if (destTexFormat != destIOSTexFormat)
TextureProceseser.ChangePlatformTextureImportSetting(tex, "iOS", maxTexSize, destIOSTexFormat);
if (destTexFormat != destAndriodTexFormat)
TextureProceseser.ChangePlatformTextureImportSetting(tex, "Android", maxTexSize, destAndriodTexFormat);
alpha = AssetDatabase.LoadAssetAtPath(alphaPath, typeof(Texture2D)) as Texture2D;
TextureProceseser.ChangeTextureImportSetting(alpha, settings);
if (destTexFormat != destIOSTexFormat)
TextureProceseser.ChangePlatformTextureImportSetting(alpha, "iOS", maxTexSize, destIOSTexFormat);
if (destTexFormat != destAndriodTexFormat)
TextureProceseser.ChangePlatformTextureImportSetting(alpha, "Android", maxTexSize, destAndriodTexFormat);
// 刷新资源。
AssetDatabase.Refresh();
}
public static void ModifyMaterial(Texture2D tex)
{
string path = AssetDatabase.GetAssetPath(tex);
int maxSize = Mathf.Max(tex.width, tex.height);
if (tex == null || string.IsNullOrEmpty(path))
{
Debug.LogWarning("This Texture is null, " + path);
return;
}
string foladerPath = StringUtils.ParseFolderPath(path);
string matPath = path.Substring(0, path.Length - ".png".Length) + ".mat";
Material mat = AssetDatabase.LoadAssetAtPath(matPath, typeof(Material)) as Material;
//int start = path.LastIndexOf("/");
// int end = path.LastIndexOf(".");
//string name = path.Substring(start + 1, end - start - 1);
string alphaPath = foladerPath + "/" + tex.name + "_a.png";
if (mat != null)
{
if (mat.shader.name.CompareTo("Unlit/Transparent Colored Split") != 0)
{
mat.shader = Shader.Find("Unlit/Transparent Colored Split");
mat.mainTexture = tex;
//mat.SetTexture("_MainTex", tex);
Texture2D alpha = AssetDatabase.LoadAssetAtPath(alphaPath, typeof(Texture2D)) as Texture2D;
if (alpha != null)
mat.SetTexture("_MaskTex", alpha);
else
Debug.LogError("ModifyMaterial : alpah is null path:" + alphaPath);
AssetDatabase.SaveAssets();
AssetDatabase.Refresh(ImportAssetOptions.ForceSynchronousImport);
}
}
}
