cube-game-plus-plus/resources/shader/ssaoBlurFragment.fs

#version 430

layout (binding = 0) uniform sampler2D ssaoSamp;

in vec2 varTex;
out float color;

void main()
{
    vec2 texelSize = 1.0 / vec2(textureSize(ssaoSamp, 0));
    float result = 0.0;
    const int radius = 2;
    for(int x = -radius; x < radius; x++) 
    {
        for(int y = -radius; y < radius; y++) 
        {
            vec2 offset = vec2(float(x), float(y)) * texelSize;
            result += texture(ssaoSamp, varTex + offset).r;
        }
    }
    result /= (radius * radius * 4);
    color = result;
}