source: data/branches/Shader_HS18/programs/Example/GLSLES/SharpenEdgesFP.glsles @ 12091

#version 100

precision mediump int;
precision mediump float;

uniform sampler2D RT;

uniform vec2 vTexelSize;
varying vec2 oUv0;
//varying vec2 uv1;

void main()
{
        vec2 usedTexelED[8];
        usedTexelED[0] = vec2(-1, -1);
        usedTexelED[1] = vec2(0, -1);
        usedTexelED[2] = vec2(1, -1);
        usedTexelED[3] = vec2(-1,  0);
        usedTexelED[4] = vec2(1,  0);
        usedTexelED[5] = vec2(-1,  1);
        usedTexelED[6] = vec2(0,  1);
        usedTexelED[7] = vec2(1,  1);

    mediump vec4 tc = texture2D(RT, oUv0);
        vec4 cAvgColor = vec4(9.0 * tc);

        for(int t=0; t<8; t++)
                cAvgColor -= texture2D(RT, oUv0 + vTexelSize * usedTexelED[t]);

        gl_FragColor = cAvgColor;
}