Export optimized premultiply and unpremultiply methods

This patch optimizes the unpremultiply method further by using a
lookup table to avoid any divisions at all.

The opportunity is taken to export both premultiply and unpremultiply
since they are commonly used methods relevant to the exported QRgb type
that can be both premultiplied and unpremultipled ARGB.

[ChangeLog][QtGui][QColor] Exported highly optimized methods for
premultiply and unpremultiply of QRgb values.

Change-Id: I658bcf57b0bc73c34c1765b64617d43b63ae820b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/src/gui/opengl/qopenglgradientcache.cpp b/src/gui/opengl/qopenglgradientcache.cpp
index 9c4fbbe013..9c312808a2 100644
--- a/src/gui/opengl/qopenglgradientcache.cpp
+++ b/src/gui/opengl/qopenglgradientcache.cpp
@@ -168,7 +168,7 @@ void QOpenGL2GradientCache::generateGradientColorTable(const QGradient& gradient
     uint current_color = ARGB_COMBINE_ALPHA(colors[0], alpha);
     qreal incr = 1.0 / qreal(size);
     qreal fpos = 1.5 * incr;
-    colorTable[pos++] = ARGB2RGBA(PREMUL(current_color));
+    colorTable[pos++] = ARGB2RGBA(qPremultiply(current_color));
 
     while (fpos <= s.first().first) {
         colorTable[pos] = colorTable[pos - 1];
@@ -177,13 +177,13 @@ void QOpenGL2GradientCache::generateGradientColorTable(const QGradient& gradient
     }
 
     if (colorInterpolation)
-        current_color = PREMUL(current_color);
+        current_color = qPremultiply(current_color);
 
     for (int i = 0; i < s.size() - 1; ++i) {
         qreal delta = 1/(s[i+1].first - s[i].first);
         uint next_color = ARGB_COMBINE_ALPHA(colors[i+1], alpha);
         if (colorInterpolation)
-            next_color = PREMUL(next_color);
+            next_color = qPremultiply(next_color);
 
         while (fpos < s[i+1].first && pos < size) {
             int dist = int(256 * ((fpos - s[i].first) * delta));
@@ -191,7 +191,7 @@ void QOpenGL2GradientCache::generateGradientColorTable(const QGradient& gradient
             if (colorInterpolation)
                 colorTable[pos] = ARGB2RGBA(INTERPOLATE_PIXEL_256(current_color, idist, next_color, dist));
             else
-                colorTable[pos] = ARGB2RGBA(PREMUL(INTERPOLATE_PIXEL_256(current_color, idist, next_color, dist)));
+                colorTable[pos] = ARGB2RGBA(qPremultiply(INTERPOLATE_PIXEL_256(current_color, idist, next_color, dist)));
             ++pos;
             fpos += incr;
         }
@@ -200,7 +200,7 @@ void QOpenGL2GradientCache::generateGradientColorTable(const QGradient& gradient
 
     Q_ASSERT(s.size() > 0);
 
-    uint last_color = ARGB2RGBA(PREMUL(ARGB_COMBINE_ALPHA(colors[s.size() - 1], alpha)));
+    uint last_color = ARGB2RGBA(qPremultiply(ARGB_COMBINE_ALPHA(colors[s.size() - 1], alpha)));
     for (;pos < size; ++pos)
         colorTable[pos] = last_color;