#version 450 core
in vec2 vTexPos;
out vec4 fColor;

uniform vec2 winSize;
uniform sampler2D screenTexture;

const float hOff = 1.0 / winSize.x;
const float vOff = 1.0 / winSize.y;
//const float verOff = 1.0 / 600.0;

//const float kernel[9] = float[](
//    0.025,0.05,0.1, 0.2, 0.25, 0.2,0.1, 0.05, 0.025
//   0.1,0.1,0.1,0.1,0.2,0.1,0.1,0.1,0.1
//    );
const float kernel[5] = float[](
         0.175,
    0.175,0.3,0.175,
         0.175
    );
const float off[5] = float[](
         vOff,
    -hOff,0.0,hOff,
         -vOff
    );

void main()
{
    vec4 sampleTex[5];
    for(int i=0; i<5; i++)
    {
        sampleTex[i] = vec4(texture(screenTexture, vTexPos + off[i]));
    }
    vec4 col = vec4(0,0,0,0);
    for (int i = 0; i < 5; i++)
        col += sampleTex[i] * kernel[i];
    fColor = col;
}