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++ VARYING vec4 TexCoordBLL;
++ VARYING vec4 TexCoordTLT;
++ VARYING vec4 TexCoordTRR;
++ VARYING vec4 TexCoordBRB;
++
++ void MAIN()
++ {
++ vec4 centerTap = texture(INPUT, INPUT_UV);
++ vec4 edgeTap = texture(INPUT, TexCoordBLL.xy)
++ + texture(INPUT, TexCoordBLL.zw)
++ + texture(INPUT, TexCoordTLT.xy)
++ + texture(INPUT, TexCoordTLT.zw)
++ + texture(INPUT, TexCoordTRR.xy)
++ + texture(INPUT, TexCoordTRR.zw)
++ + texture(INPUT, TexCoordBRB.xy)
++ + texture(INPUT, TexCoordBRB.zw);
++ vec3 edgeDetect = 8.0 * (centerTap.rgb - (0.125 * edgeTap.rgb));
++ edgeDetect = clamp(edgeDetect, 0.0, centerTap.a);
++
++ FRAGCOLOR = vec4(mix(centerTap.rgb, edgeDetect, edgeStrength), centerTap.a);
++ }