Fix 1684240: Several places were multiplying the A component of the color by itself...

git-svn-id: http://svn.voria.com/code@363 1f10aa63-cdf2-0310-b900-c93c546f37ac

diff --git a/synfig-core/trunk/src/synfig/gradient.cpp b/synfig-core/trunk/src/synfig/gradient.cpp
index ff8a581..e206b48 100644 (file)
--- a/synfig-core/trunk/src/synfig/gradient.cpp
+++ b/synfig-core/trunk/src/synfig/gradient.cpp
@@ -107,11 +107,8 @@ supersample_helper(const synfig::Gradient::CPoint &color1, const synfig::Gradien
        if(color1.pos>=begin && color2.pos<end)
        {
                weight=color2.pos-color1.pos;
-               ColorAccumulator ret=Color::blend(color2.color,color1.color, 0.5, Color::BLEND_STRAIGHT);
-               ret.set_r(ret.get_r()*ret.get_a());
-               ret.set_g(ret.get_g()*ret.get_a());
-               ret.set_b(ret.get_b()*ret.get_a());
-               return ret*weight;
+               ColorAccumulator ret=Color::blend(color2.color,color1.color, 0.5, Color::BLEND_STRAIGHT).premult_alpha()*weight;
+               return ret;
        }
        if(color1.pos>=begin && color2.pos>=end)
        {
@@ -119,11 +116,8 @@ supersample_helper(const synfig::Gradient::CPoint &color1, const synfig::Gradien
                float pos((end+color1.pos)*0.5);
                float amount((pos-color1.pos)/(color2.pos-color1.pos));
                //if(abs(amount)>1)amount=(amount>0)?1:-1;
-               ColorAccumulator ret(Color::blend(color2.color,color1.color, amount, Color::BLEND_STRAIGHT));
-               ret.set_r(ret.get_r()*ret.get_a());
-               ret.set_g(ret.get_g()*ret.get_a());
-               ret.set_b(ret.get_b()*ret.get_a());
-               return ret*weight;
+               ColorAccumulator ret(Color::blend(color2.color,color1.color, amount, Color::BLEND_STRAIGHT).premult_alpha()*weight);
+               return ret;
        }
        if(color1.pos<begin && color2.pos<end)
        {
@@ -131,11 +125,8 @@ supersample_helper(const synfig::Gradient::CPoint &color1, const synfig::Gradien
                float pos((begin+color2.pos)*0.5);
                float amount((pos-color1.pos)/(color2.pos-color1.pos));
                //if(abs(amount)>1)amount=(amount>0)?1:-1;
-               ColorAccumulator ret(Color::blend(color2.color,color1.color, amount, Color::BLEND_STRAIGHT));
-               ret.set_r(ret.get_r()*ret.get_a());
-               ret.set_g(ret.get_g()*ret.get_a());
-               ret.set_b(ret.get_b()*ret.get_a());
-               return ret*weight;
+               ColorAccumulator ret(Color::blend(color2.color,color1.color, amount, Color::BLEND_STRAIGHT).premult_alpha()*weight);
+               return ret;
        }
        synfig::error("color1.pos=%f",color1.pos);
        synfig::error("color2.pos=%f",color2.pos);
@@ -285,7 +276,7 @@ synfig::Gradient::operator()(const Real &x,float supersample)const
                        {
                                weight=x-iter->pos;
                                //weight*=iter->color.get_a();
-                               pool+=ColorAccumulator(iter->color)*(float)iter->color.get_a()*weight;
+                               pool+=ColorAccumulator(iter->color).premult_alpha()*weight;
                                divisor+=weight;
                        }
                        else
@@ -296,7 +287,7 @@ synfig::Gradient::operator()(const Real &x,float supersample)const
                                        {
                                                weight=iter2->pos-(begin_sample);
                                                //weight*=iter2->color.get_a();
-                                               pool+=ColorAccumulator(iter2->color)*(float)iter2->color.get_a()*weight;
+                                               pool+=ColorAccumulator(iter2->color).premult_alpha()*weight;
                                                divisor+=weight;
                                                break;
                                        }
@@ -313,7 +304,7 @@ synfig::Gradient::operator()(const Real &x,float supersample)const
                                if(next2==end())
                                {
                                        weight=(end_sample)-iter2->pos;
-                                       pool+=ColorAccumulator(iter2->color)*(float)iter2->color.get_a()*weight;
+                                       pool+=ColorAccumulator(iter2->color).premult_alpha()*weight;
                                        divisor+=weight;
                                        break;
                                }