From d3bf0d79d94f7e6b1a0f78a634b7ddd76a492656 Mon Sep 17 00:00:00 2001
From: Xiangyin Ma <x1.ma@samsung.com>
Date: Fri, 29 Apr 2016 17:33:44 +0100
Subject: [PATCH] Use pre-multiplied alpha format in GradientRenderer

Change-Id: Ic363699481c40dcb51c3ba9507be6f7458eb6d8c
---
 .../controls/renderers/gradient/gradient-renderer.cpp     | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/dali-toolkit/internal/controls/renderers/gradient/gradient-renderer.cpp b/dali-toolkit/internal/controls/renderers/gradient/gradient-renderer.cpp
index eec8029..6b35829 100644
--- a/dali-toolkit/internal/controls/renderers/gradient/gradient-renderer.cpp
+++ b/dali-toolkit/internal/controls/renderers/gradient/gradient-renderer.cpp
@@ -183,6 +183,7 @@ GradientRenderer::GradientRenderer( RendererFactoryCache& factoryCache )
 : ControlRenderer( factoryCache ),
   mGradientType( LINEAR )
 {
+  mImpl->mFlags |= Impl::IS_PREMULTIPLIED_ALPHA;
 }
 
 GradientRenderer::~GradientRenderer()
@@ -275,7 +276,17 @@ void GradientRenderer::DoCreatePropertyMap( Property::Map& map ) const
   for( unsigned int i=0; i<stops.Count(); i++ )
   {
     offsets.PushBack( stops[i].mOffset );
-    colors.PushBack( stops[i].mStopColor );
+    if( EqualsZero(stops[i].mStopColor.a) )
+    {
+      colors.PushBack( Vector4::ZERO );
+    }
+    else
+    {
+      colors.PushBack( Vector4( stops[i].mStopColor.r / stops[i].mStopColor.a,
+                                stops[i].mStopColor.g / stops[i].mStopColor.a,
+                                stops[i].mStopColor.b / stops[i].mStopColor.a,
+                                stops[i].mStopColor.a));
+    }
   }
 
   map.Insert( STOP_OFFSET_NAME, offsets );
@@ -381,7 +392,7 @@ bool GradientRenderer::NewGradient(Type gradientType, const Property::Map& prope
       {
         if( (colorArray->GetElementAt(i)).Get(color) )
         {
-          mGradient->AddStop( offsetArray[i], color);
+          mGradient->AddStop( offsetArray[i], Vector4(color.r*color.a, color.g*color.a, color.b*color.a, color.a));
           numValidStop++;
         }
       }
-- 
2.7.4