uniform float     time;
uniform vec2      resolution;
uniform vec2      mouse;

#define MAX_ITER 3

void main(void) {
	vec2 v_texCoord = gl_FragCoord.xy / min(resolution.x, resolution.y) / 2.0;

	vec2 p =  v_texCoord * 8.0 - vec2(20.0);
	vec2 i = p;
	float c = 1.0;
	float inten = .05;

	for (int n = 0; n < MAX_ITER; n++) {
		float t = time * (1.0 - (3.0 / float(n+1)));

		i = p + vec2(cos(t - i.x) + sin(t + i.y),
		sin(t - i.y) + cos(t + i.x));

		c += 1.0/length(vec2(p.x / (sin(i.x+t)/inten),
		p.y / (cos(i.y+t)/inten)));
	}

	c /= float(MAX_ITER);
	c = 1.5 - sqrt(c);

	vec4 texColor = vec4(0.001, 0.1, 0.1, 1.);

	texColor.rgb *= (1.0 / (1.0 - (c + 0.05)));

	gl_FragColor = texColor;
}