Merge pull request cocos2d#14722 from newnon/v3.10_webp_improvement

WebP loading improvements WebP loaded as premultiplied alpha if it has

Author: zilongshanren

cocos/platform/CCImage.cpp

@@ -2121,19 +2121,19 @@ bool Image::initWithWebpData(const unsigned char * data, ssize_t dataLen)
         if (WebPGetFeatures(static_cast<const uint8_t*>(data), dataLen, &config.input) != VP8_STATUS_OK) break;
         if (config.input.width == 0 || config.input.height == 0) break;
 
-        config.output.colorspace = MODE_RGBA;
-        _renderFormat = Texture2D::PixelFormat::RGBA8888;
+        config.output.colorspace = config.input.has_alpha?MODE_rgbA:MODE_RGB;
+        _renderFormat = config.input.has_alpha?Texture2D::PixelFormat::RGBA8888:Texture2D::PixelFormat::RGB888;
         _width    = config.input.width;
         _height   = config.input.height;
 
-        //webp doesn't have premultipliedAlpha
-        _hasPremultipliedAlpha = false;
+        //we ask webp to give data with premultiplied alpha
+        _hasPremultipliedAlpha = config.input.has_alpha;
 
-        _dataLen = _width * _height * 4;
+        _dataLen = _width * _height * (config.input.has_alpha?4:3);
         _data = static_cast<unsigned char*>(malloc(_dataLen * sizeof(unsigned char)));
 
         config.output.u.RGBA.rgba = static_cast<uint8_t*>(_data);
-        config.output.u.RGBA.stride = _width * 4;
+        config.output.u.RGBA.stride = _width * (config.input.has_alpha?4:3);
         config.output.u.RGBA.size = _dataLen;
         config.output.is_external_memory = 1;
 

tests/cpp-tests/Classes/Texture2dTest/Texture2dTest.cpp

@@ -81,6 +81,7 @@ Texture2DTests::Texture2DTests()
     ADD_TEST_CASE(TextureTGA);
 #if (CC_TARGET_PLATFORM != CC_PLATFORM_WINRT)
     ADD_TEST_CASE(TextureWEBP);
+    ADD_TEST_CASE(TextureWEBPNoAlpha)
 #endif
     ADD_TEST_CASE(TexturePixelFormat);
     ADD_TEST_CASE(TextureBlend);
@@ -261,11 +262,36 @@ void TextureWEBP::onEnter()
     img->setPosition(Vec2( s.width/2.0f, s.height/2.0f));
     addChild(img);
     log("%s\n", Director::getInstance()->getTextureCache()->getCachedTextureInfo().c_str());
+    Texture2D* texture = Director::getInstance()->getTextureCache()->getTextureForKey("Images/test_image.webp");
+    log("pixel format:%d, premultiplied alpha:%d\n", texture->getPixelFormat(), texture->hasPremultipliedAlpha());
 }
 
 std::string TextureWEBP::title() const
 {
-    return "WEBP Test";
+    return "WEBP with alpha Test";
+}
+
+//------------------------------------------------------------------
+//
+// TextureWEBPNoAlpha
+//
+//------------------------------------------------------------------
+void TextureWEBPNoAlpha::onEnter()
+{
+    TextureDemo::onEnter();
+    auto s = Director::getInstance()->getWinSize();
+    
+    auto img = Sprite::create("Images/test_image_no_alpha.webp");
+    img->setPosition(Vec2( s.width/2.0f, s.height/2.0f));
+    addChild(img);
+    log("%s\n", Director::getInstance()->getTextureCache()->getCachedTextureInfo().c_str());
+    Texture2D* texture = Director::getInstance()->getTextureCache()->getTextureForKey("Images/test_image_no_alpha.webp");
+    log("pixel format:%d, premultiplied alpha:%d\n", texture->getPixelFormat(), texture->hasPremultipliedAlpha());
+}
+
+std::string TextureWEBPNoAlpha::title() const
+{
+    return "WEBP without alpha Test";
 }
 
 //------------------------------------------------------------------

tests/cpp-tests/Classes/Texture2dTest/Texture2dTest.h

@@ -79,6 +79,14 @@ class TextureWEBP : public TextureDemo
     virtual void onEnter() override;
 };
 
+class TextureWEBPNoAlpha : public TextureDemo
+{
+public:
+    CREATE_FUNC(TextureWEBPNoAlpha);
+    virtual std::string title() const override;
+    virtual void onEnter() override;
+};
+
 class TextureMipMap : public TextureDemo
 {
 public: