// Trans flag, gently waving. The white stripe uses the white LEDs.

vec3 stripe(int k) {
    if (k == 0 || k == 4) return vec3(0.25, 0.75, 1.0);   // blue
    if (k == 1 || k == 3) return vec3(1.0, 0.35, 0.55);   // pink
    return vec3(1.0);                                     // white
}

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
    float i = floor(fragCoord.x / iResolution.x * 16.0);
    float x = (i + 0.5) / 13.0;
    float p = x * 5.0 + 0.5 * sin(iTime * 0.3) + 0.25 * sin(x * 6.0 - iTime * 0.7);
    p = clamp(p, 0.0, 4.999);
    int k = int(floor(p));
    float f = smoothstep(0.7, 1.0, fract(p));
    vec3 col = mix(stripe(k), stripe(min(k + 1, 4)), f);
    col *= 0.9 + 0.1 * sin(i * 0.5 - iTime * 0.8);
    fragColor = vec4(col * 0.8, 1.0);
}