#define PI 3.1416
#define PI2 (2.0 * PI)

/*
  Complex square
 */
highp vec2 to_the_2(highp vec2 z){
    highp vec2 old_z;
    // Keep the current (old) value
    old_z = z;

    // Set new values according to math
    z.x = pow(z.x,2.0) - pow(z.y,2.0);
    z.y = 2.0 * old_z.x * old_z.y;

    return z;
}


vec4 mandelbrot(vec2 UV){
    float x = UV.x / (iResolution.y / iResolution.x);
    float y = UV.y;

    vec4 col = vec4(0.0);

    vec2 c = vec2( -y + 0.5, x - 0.5);
    vec2 z = vec2(0.0, 0.0);
	c *= 4.0;
    c.x -= 0.5;
    float maxit = 0.0;

    bool in_set = true;

   	for(int i = 0; i < 50; i++){
       	z = to_the_2(z) + c;

        if(length(z) > 2.0){
        	maxit = float(i);
            in_set = false;
        	break;
        }
    }

    if(!in_set){
    	col.g = maxit/50.0;
    } else {
        col.g = maxit/50.0;
        col.r = length(z);
    }
    col.b = maxit/50.0;

    col.a = 1.0;

    return col;
}

vec4 glitch_ball(vec2 pos){
    float x = pos.x;
    float y = pos.y;
    vec4 col = vec4(0.0);
    float time = iGlobalTime;
    x = x - floor(x * 260.0) + time/100.0;
    y = y - floor(y * 30.0) + time/100.0;

    col.r = sin(13.0 * x + y + PI2 * time + 0.3);
    col.g = sin((13.0 + 0.006 * cos(time*PI2 + 30.0 * pos.x)) * x + y + PI2 * time + 0.3);
    col.b = sin((13.0) * x + y + PI2 * time + 0.3);

    col = abs(col);

    if(distance(pos, vec2(0.5,0.5)) > 0.4){
    	col *= 0.0;
    }

    col.a = 1.0;
    return col;
}



void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
	vec2 uv = fragCoord.xy / iResolution.xy;
	fragColor = mandelbrot(uv) * glitch_ball(uv);

}