Color = tex2D( postTex, Tex.xy);
Color += tex2D( postTex, Tex.xy+0.001);
Color += tex2D( postTex, Tex.xy+0.003);
Color += tex2D( postTex, Tex.xy+0.005);
Color = Color / 3.5;

If I understand it right, this blurs the screen and makes everything a bit brighter. if you just want to have the hole screen brighter, it should be enough to have it like this:

Color = tex2D( postTex, Tex.xy)*1.2; //1.2 is the faktor for brightening

Slin

PS: I don´t think that this is a real bloom effekt... Why not use the Sylex Bloom?

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