#version 330 core
out vec4 FragColor;

in vec2 TexCoords;

uniform sampler2D image;
uniform int horizontal;

const float weights[5] = float[](0.227027, 0.1945946, 0.1216216, 0.054054, 0.016216);

void main()
{
    vec2 texel = 1.0 / vec2(textureSize(image, 0));
    vec2 direction = horizontal != 0 ? vec2(texel.x, 0.0) : vec2(0.0, texel.y);

    vec3 color = texture(image, TexCoords).rgb * weights[0];
    for (int i = 1; i < 5; i++) {
        color += texture(image, TexCoords + direction * float(i)).rgb * weights[i];
        color += texture(image, TexCoords - direction * float(i)).rgb * weights[i];
    }

    FragColor = vec4(color, 1.0);
}