X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=dali-toolkit%2Finternal%2Fcontrols%2Frenderers%2Fimage%2Fimage-renderer.cpp;h=7862d5326809420c683e4ddb66c12dff2ce1b684;hb=d43575da616e1370372b1331f47dce36dc4ac145;hp=8b13a4e5c7987e02eeb3afe7c86a072c9ba38efb;hpb=0a374bcfcf4fb906d2c8256cfee595e6193f4dbf;p=platform%2Fcore%2Fuifw%2Fdali-toolkit.git

diff --git a/dali-toolkit/internal/controls/renderers/image/image-renderer.cpp b/dali-toolkit/internal/controls/renderers/image/image-renderer.cpp
index 8b13a4e..7862d53 100644
--- a/dali-toolkit/internal/controls/renderers/image/image-renderer.cpp
+++ b/dali-toolkit/internal/controls/renderers/image/image-renderer.cpp
@@ -73,6 +73,10 @@ const char * const DONT_CARE("dontCare");
 const std::string TEXTURE_UNIFORM_NAME = "sTexture";
 const std::string ATLAS_RECT_UNIFORM_NAME = "uAtlasRect";
 const std::string PIXEL_AREA_UNIFORM_NAME = "pixelArea";
+
+// Set this uniform to 1.0 for conventional alpha blending; if pre-multiplied alpha blending, set this uniform to 0.0
+const std::string ALPHA_BLENDING_UNIFORM_NAME = "uAlphaBlending";
+
 const Vector4 FULL_TEXTURE_RECT(0.f, 0.f, 1.f, 1.f);
 
 const char* VERTEX_SHADER = DALI_COMPOSE_SHADER(
@@ -98,10 +102,11 @@ const char* FRAGMENT_SHADER = DALI_COMPOSE_SHADER(
   varying mediump vec2 vTexCoord;\n
   uniform sampler2D sTexture;\n
   uniform lowp vec4 uColor;\n
+  uniform lowp float uAlphaBlending; // Set to 1.0 for conventional alpha blending; if pre-multiplied alpha blending, set to 0.0
   \n
   void main()\n
   {\n
-    gl_FragColor = texture2D( sTexture, vTexCoord ) * uColor;\n
+    gl_FragColor = texture2D( sTexture, vTexCoord ) * vec4( uColor.rgb*max( uAlphaBlending, uColor.a ), uColor.a );\n
   }\n
 );
 
@@ -201,7 +206,8 @@ ImageRenderer::ImageRenderer( RendererFactoryCache& factoryCache, ImageAtlasMana
   mAtlasManager( atlasManager ),
   mDesiredSize(),
   mFittingMode( FittingMode::DEFAULT ),
-  mSamplingMode( SamplingMode::DEFAULT )
+  mSamplingMode( SamplingMode::DEFAULT ),
+  mIsAlphaPreMultiplied( false )
 {
 }
 
@@ -402,6 +408,7 @@ Renderer ImageRenderer::CreateRenderer() const
       {
         shader.RegisterProperty( ATLAS_RECT_UNIFORM_NAME, FULL_TEXTURE_RECT );
         shader.RegisterProperty( PIXEL_AREA_UNIFORM_NAME, FULL_TEXTURE_RECT );
+        shader.RegisterProperty( ALPHA_BLENDING_UNIFORM_NAME, 1.f );
       }
     }
   }
@@ -485,6 +492,8 @@ void ImageRenderer::DoSetOnStage( Actor& actor )
   {
     InitializeRenderer( mImage );
   }
+
+  EnablePreMultipliedAlpha( mIsAlphaPreMultiplied );
 }
 
 void ImageRenderer::DoSetOffStage( Actor& actor )
@@ -609,6 +618,7 @@ Shader ImageRenderer::GetImageShader( RendererFactoryCache& factoryCache )
     factoryCache.SaveShader( RendererFactoryCache::IMAGE_SHADER, shader );
     shader.RegisterProperty( ATLAS_RECT_UNIFORM_NAME, FULL_TEXTURE_RECT );
     shader.RegisterProperty( PIXEL_AREA_UNIFORM_NAME, FULL_TEXTURE_RECT );
+    shader.RegisterProperty( ALPHA_BLENDING_UNIFORM_NAME, 1.f );
   }
   return shader;
 }
@@ -696,6 +706,37 @@ void ImageRenderer::SetImage( Actor& actor, const Image& image )
   }
 }
 
+void ImageRenderer::EnablePreMultipliedAlpha( bool preMultipled )
+{
+  mIsAlphaPreMultiplied = preMultipled;
+  if( mImpl->mRenderer )
+  {
+    Material material = mImpl->mRenderer.GetMaterial();
+
+    if( preMultipled )
+    {
+      material.SetBlendFunc( BlendingFactor::ONE, BlendingFactor::ONE_MINUS_SRC_ALPHA,
+                             BlendingFactor::ONE, BlendingFactor::ONE );
+      if( !mImpl->mCustomShader || mImpl->mCustomShader->mVertexShader.empty())
+      {
+        material.RegisterProperty( ALPHA_BLENDING_UNIFORM_NAME, 0.f );
+      }
+    }
+    else
+    {
+      // using default blend func
+      material.SetBlendFunc( BlendingFactor::SRC_ALPHA, BlendingFactor::ONE_MINUS_SRC_ALPHA,
+                              BlendingFactor::ONE, BlendingFactor::ONE_MINUS_SRC_ALPHA );
+
+      Property::Index index = material.GetPropertyIndex( ALPHA_BLENDING_UNIFORM_NAME );
+      if( index != Property::INVALID_INDEX ) // only set value when the property already exist on the Material
+      {
+        material.SetProperty( index, 1.f );
+      }
+    }
+  }
+}
+
 void ImageRenderer::ApplyImageToSampler( const Image& image )
 {
   if( image )