#define RED vec4(1., 0., 0., 1.)
#define BLACK vec4(0.)

float PI = acos(-1.);

float deg2rad(float x){
	return x / 180. * PI;
}

vec2 rad2cod(float r, float t){
	return vec2(r * cos(t), r * sin(t));
}

float norm2(vec2 xy){
	return sqrt(xy.x * xy.x + xy.y * xy.y);
}

int seed = 20150118;
int rand(){
	return seed = seed * 0xdefaced + 1;
}

float dir = -1.;

vec4 draw(vec2 fragCoord, vec2 center){
	float r = iTime * dir;
    mat2 rot = mat2(cos(r), -sin(r), sin(r), cos(r));
    float var = sin(texture(iChannel0, vec2(iTime, 0.)).x);
    vec2 xy = rot * (fragCoord.xy - center);
    vec4 col = vec4(-1.);
    if(norm2(xy) < 100. + var * 20.){
    	col = RED;
    }

    if(norm2(xy) < 15. + var * 20.){
    	col = BLACK;
    }
    if(70. <= norm2(xy) && norm2(xy) <= 72.5){
    	col = BLACK;
    }

    if(norm2(xy - rad2cod(70., deg2rad(0.0))) < 15. + var * 20.){
     	col = BLACK;
    }
    if(norm2(xy - rad2cod(70., deg2rad(120.0))) < 15. + var * 20.){
     	col = BLACK;
    }
    if(norm2(xy - rad2cod(70., deg2rad(240.0))) < 15. + var * 20.){
     	col = BLACK;
    }

    return col;
}

void mainImage( out vec4 fragColor, in vec2 fragCoord ){
    float offset = mod(iTime * 100., 360.);
    vec4 col = vec4(1.);
    vec2 xy = fragCoord - iResolution.xy / 2.0;
	float var = sin(texture(iChannel0, vec2(iTime, 0.)).x);
    if(norm2(xy) < 400.){
    	col = BLACK;
    }
    if(norm2(xy) < 40. + var * 60.){
    	col = RED;
    }
    if(240. < norm2(xy) && norm2(xy) < 245.){
    	col = RED;
    }

    if(norm2(xy - rad2cod(250., deg2rad(0.0   + offset))) < 300.){
  		vec4 tmp = draw(fragCoord, iResolution.xy / 2. + rad2cod(250., deg2rad(0.0   + offset)));
        if(tmp != vec4(-1.))
            col = tmp;
    }
    if(norm2(xy - rad2cod(250., deg2rad(120.0   + offset))) < 300.){
  		vec4 tmp = draw(fragCoord, iResolution.xy / 2. + rad2cod(250., deg2rad(120.0   + offset)));
        if(tmp != vec4(-1.))
            col = tmp;
    }
    if(norm2(xy - rad2cod(250., deg2rad(240.0   + offset))) < 300.){
  		vec4 tmp = draw(fragCoord, iResolution.xy / 2. + rad2cod(250., deg2rad(240.0   + offset)));
        if(tmp != vec4(-1.))
            col = tmp;
    }
    if(var > 0.4)
        col = vec4(1.) - col;
    fragColor = col;
}