shaders: minor premultiplication fixes

2 files changed, 6 insertions, 5 deletions

diff --git a/src/render/shaders/Border.hpp b/src/render/shaders/Border.hpp
index d881dc5b..4e2d485d 100644
--- a/src/render/shaders/Border.hpp
+++ b/src/render/shaders/Border.hpp
@@ -109,11 +109,14 @@ void main() {
             discard;
     }
 
-    if (pixColor[3] == 0.0)
+    if (additionalAlpha == 0.0)
         discard;
 
     pixColor = getColorForCoord(v_texcoord);
+    pixColor.rgb *= pixColor[3];
 
-    gl_FragColor = pixColor * alpha * additionalAlpha;
+    pixColor *= alpha * additionalAlpha;
+
+    gl_FragColor = pixColor;
 }
 )#";
diff --git a/src/render/shaders/Shadow.hpp b/src/render/shaders/Shadow.hpp
index 49f548d7..2c7b07b2 100644
--- a/src/render/shaders/Shadow.hpp
+++ b/src/render/shaders/Shadow.hpp
@@ -79,9 +79,7 @@ void main() {
     }
 
     // premultiply
-    pixColor[0] *= pixColor[3];
-    pixColor[1] *= pixColor[3];
-    pixColor[2] *= pixColor[3];
+    pixColor.rgb *= pixColor[3];
 
 	gl_FragColor = pixColor;
 })#";