scrapbox_background.frag

precision mediump float;

uniform float time;
uniform vec2 resolution;

vec3 gradient(vec2 p) {
	return vec3(0.5, abs(clamp(p.y, -0.8, 0.8)) , 0.7);
}

void main(void) {
    vec2 p = (gl_FragCoord.xy * 2.0 - resolution) / min(resolution.x, resolution.y);
	
	float u = sin((atan(p.y, p.x) * 0.3 + tan(time)) * 20.0) * 0.01;

    float col = 0.02 / abs(0.6 + u - length(p));
	float s = smoothstep(0.2, 1.8, cos(p.x));
	col += s;
	vec3 base = vec3(col) * gradient(p) * smoothstep(0., 1., sin(time));
	
    gl_FragColor = vec4(base * vec3(0.4) + vec3(0.08, 0.11, 0.12), 1.0);
}