vg_common_svg: Gradient stop color use premultiplied color.

Summary:
The parsed color is straight color.
evas use premultiplied color.

Test Plan:
Sample SVG
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100">
  <defs>
    <linearGradient id="linearGradient1" x1="0" y1="0" x2="0.2" y2="0.2" spreadMethod="reflect">
      <stop style="stop-color:#ff0000;stop-opacity:1;" offset="0"/>
      <stop style="stop-color:#0000ff;stop-opacity:1;" offset="1"/>
    </linearGradient>
    <radialGradient id="radialGradient222" r="0.2" cx="0.3" cy="0.3" spreadMethod="reflect">
      <stop style="stop-color:#ffFF00;stop-opacity:0.1;" offset="0"/>
      <stop style="stop-color:#00FFff;stop-opacity:1;"   offset="1"/>
    </radialGradient>
    <radialGradient id="radialGradient333" r="0.2" cx="0.3" cy="0.3" spreadMethod="reflect">
      <stop style="stop-color:#00FF00;stop-opacity:0.1;" offset="0"/>
      <stop style="stop-color:#FF00ff;stop-opacity:1;"   offset="1"/>
    </radialGradient>
   </defs>
  <rect x="0" y="0" width="100" height="100" fill="url(#linearGradient1)"/>
  <rect x="50" y="50" width="50" height="50" fill="url(#radialGradient222)"/>
  <rect x="0" y="0" width="50" height="50" fill="url(#radialGradient333)"/>
</svg>

Reviewers: Hermet, kimcinoo, smohanty

Reviewed By: Hermet

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D9338

Change-Id: Ifcc1d6b94aab190494afa4f1800e2ed7cf2ffaed

diff --git a/src/static_libs/vg_common/vg_common_svg.c b/src/static_libs/vg_common/vg_common_svg.c
index 20a167c..e3866e2 100644 (file)
--- a/src/static_libs/vg_common/vg_common_svg.c
+++ b/src/static_libs/vg_common/vg_common_svg.c
@@ -683,13 +683,16 @@ _apply_gradient_property(Svg_Style_Gradient *g, Efl_VG *vg, Efl_VG *parent, Vg_F
    stop_count = eina_list_count(g->stops);
    if (stop_count)
      {
+        double opacity;
         stops = calloc(stop_count, sizeof(Efl_Gfx_Gradient_Stop));
         i = 0;
         EINA_LIST_FOREACH(g->stops, l, stop)
           {
-             stops[i].r = stop->r;
-             stops[i].g = stop->g;
-             stops[i].b = stop->b;
+             // Use premultiplied color
+             opacity = (double)stop->a / 255;
+             stops[i].r = stop->r * opacity;
+             stops[i].g = stop->g * opacity;
+             stops[i].b = stop->b * opacity;
              stops[i].a = stop->a;
              stops[i].offset = stop->offset;
              i++;