gistfile1.diff

Index: data/stdshader.cfg
===================================================================
--- data/stdshader.cfg	(revision 1913)
+++ data/stdshader.cfg	(working copy)
@@ -1538,6 +1538,36 @@
 lazyshader 0 "gbr"    [ @fsvs END ] [ @fsps MOV result.color, sample.yzxw; END ]
 lazyshader 0 "bw"     [ @fsvs END ] [ @fsps DP3 result.color, sample, 0.333; END ]
 
+lazyshader 4 "desaturate" [ varying vec2 TX;
+
+void main()
+{
+	TX = gl_MultiTexCoord0.st;
+	gl_Position = gl_Vertex;
+} ] [ #extension GL_ARB_texture_rectangle : require
+uniform sampler2DRect tex0;
+varying vec2 TX;
+
+float GSValue ( vec3 colour )
+{
+	return dot(vec3(0.19, 0.7, 0.11), colour);
+}
+
+vec3 Transform ( vec3 colour )
+{
+	float gs = GSValue(colour);
+	vec3 gsColour = vec3(gs, gs, gs);
+	gs = pow(gs * 0.9, 0.3);
+	return mix(gsColour, colour, gs);
+}
+
+void main()
+{
+	vec4 sample = texture2DRect(tex0, TX);
+	sample.rgb = Transform(sample.rgb);
+	gl_FragColor = sample;
+} ]
+
 // sobel
 
 lazyshader 0 "sobel" [ @fsvs @setup4corners END ] [