kwin/effects/invert/data/invert.frag
Lucas Murray 491d61b949 Correctly handle pre-multiplied textures in the invert effect.
BUG: 212339

svn path=/trunk/KDE/kdebase/workspace/; revision=1042534
2009-10-30 01:34:03 +00:00

27 lines
824 B
GLSL

uniform sampler2D winTexture;
uniform float textureWidth;
uniform float textureHeight;
uniform float opacity;
uniform float brightness;
uniform float saturation;
// Converts pixel coordinates to texture coordinates
vec2 pix2tex( vec2 pix )
{
return vec2( pix.s / textureWidth, pix.t / textureHeight );
}
void main()
{
vec4 tex = texture2D( winTexture, pix2tex( gl_TexCoord[0].st ));
tex = vec4(( vec3( 1.0 ) - tex.rgb / vec3( tex.a )) * vec3( tex.a * opacity ), tex.a * opacity );
if( saturation != 1.0 )
{
vec3 desaturated = tex.rgb * vec3( 0.30, 0.59, 0.11 );
desaturated = vec3( dot( desaturated, tex.rgb ));
tex.rgb = tex.rgb * vec3( saturation ) + desaturated * vec3( 1.0 - saturation );
}
tex.rgb = tex.rgb * vec3( brightness );
gl_FragColor = tex;
}