gaussian.glsl

precision highp float;
uniform vec3 origResolution;
uniform vec3 iResolution;
uniform sampler2D iChannel0;
uniform bool flip;
uniform vec2 direction;
vec4 blur9_1_0(sampler2D image, vec2 uv, vec2 resolution, vec2 direction, vec2 a) {
    vec4 color = vec4(0.0);
    vec2 off1 = (vec2(1.3846153846) * direction) / resolution;
    vec2 off2 = (vec2(3.2307692308) * direction) / resolution;
    if (direction.x == .0 && (uv * resolution).y < (resolution - a).y || direction.y == .0 && (uv * resolution).x > a.x) {
        return texture2D(image, uv);
    }
    vec2 add1 = uv + off1;
    vec2 sub1 = uv - off1;
    vec2 add2 = uv + off2;
    vec2 sub2 = uv - off2;
    vec2 rpos = a / resolution;
    bool horizontal = direction.y == .0;
    color += texture2D(image, uv) * 0.2270270270;
    color += texture2D(image, (horizontal ? add1.x >= rpos.x : add1.y >= 1.) ? uv : add1) * 0.3162162162;
    color += texture2D(image, (horizontal ? sub1.x <= .0 : sub1.y <= (1. - rpos).y) ? uv : sub1) * 0.3162162162;
    color += texture2D(image, (horizontal ? add2.x >= rpos.x : add2.y >= 1.) ? uv : add2) * 0.0702702703;
    color += texture2D(image, (horizontal ? sub2.x <= .0 : sub2.y <= (1. - rpos).y) ? uv : sub2) * 0.0702702703;
    return color;
}
void main() {
    vec2 uv = vec2(gl_FragCoord.xy / iResolution.xy);
    if (flip) {
        uv.y = 1.0 - uv.y;
    }
    gl_FragColor = blur9_1_0(iChannel0, uv, iResolution.xy, direction, origResolution.xy);
}