From: Dana Jansens <danakj@orodu.net>
Date: Sun, 10 Feb 2008 06:51:34 +0000 (-0500)
Subject: make white font shadows (negative shadowtint) work right.. this has been busted a... 
X-Git-Url: https://git.dogcows.com/gitweb?a=commitdiff_plain;h=f0d31a52b7eb0682f4b114c475f9212355720051;p=chaz%2Fopenbox

make white font shadows (negative shadowtint) work right.. this has been busted a long time. thank you nvidia.
---

diff --git a/render/font.c b/render/font.c
index 356b9c6e..369f262e 100644
--- a/render/font.c
+++ b/render/font.c
@@ -258,9 +258,20 @@ void RrFontDraw(XftDraw *d, RrTextureText *t, RrRect *area)
     }
 
     if (t->shadow_offset_x || t->shadow_offset_y) {
-        c.color.red = t->shadow_color->r | t->shadow_color->r << 8;
-        c.color.green = t->shadow_color->g | t->shadow_color->g << 8;
-        c.color.blue = t->shadow_color->b | t->shadow_color->b << 8;
+        /* From nvidia's readme (chapter 23):
+
+           When rendering to a 32-bit window, keep in mind that the X RENDER
+           extension, used by most composite managers, expects "premultiplied
+           alpha" colors. This means that if your color has components (r,g,b)
+           and alpha value a, then you must render (a*r, a*g, a*b, a) into the
+           target window.
+        */
+        c.color.red = (t->shadow_color->r | t->shadow_color->r << 8) *
+            t->shadow_alpha / 255;
+        c.color.green = (t->shadow_color->g | t->shadow_color->g << 8) *
+            t->shadow_alpha / 255;
+        c.color.blue = (t->shadow_color->b | t->shadow_color->b << 8) *
+            t->shadow_alpha / 255;
         c.color.alpha = 0xffff * t->shadow_alpha / 255;
         c.pixel = t->shadow_color->pixel;