precision mediump float;

uniform float u_time;
uniform vec2 u_mouse;
uniform vec2 u_resolution;
varying vec2 v_uv;

#define PI 3.14159265359

float hash(vec2 p) {
    p = fract(p * vec2(234.34, 435.345));
    p += dot(p, p + 34.23);
    return fract(p.x * p.y);
}

float noise(vec2 p) {
    vec2 i = floor(p);
    vec2 f = fract(p);
    f = f * f * (3.0 - 2.0 * f);
    return mix(
        mix(hash(i), hash(i + vec2(1.0, 0.0)), f.x),
        mix(hash(i + vec2(0.0, 1.0)), hash(i + vec2(1.0, 1.0)), f.x),
        f.y
    );
}

mat2 rot2d(float a) {
    float s = sin(a);
    float c = cos(a);
    return mat2(c, -s, s, c);
}

void main() {
    vec2 uv = v_uv;
    vec2 aspect = vec2(u_resolution.x/u_resolution.y, 1.0);
    uv = (uv - 0.5) * aspect;
    
    float mouseInfluence = length(u_mouse - v_uv) * 2.0;
    
    vec3 color = vec3(0.0);
    
    for(float i = 0.0; i < 3.0; i++) {
        vec2 p = uv;
        float t = u_time * 0.5 + i * PI * 2.0 / 3.0;
        
        p *= rot2d(t * 0.3);
        p *= 1.0 + sin(t) * 0.2;
        p *= 5.0 + sin(mouseInfluence * PI) * 2.0;
        
        float n = noise(p + t);
        float n2 = noise(p * 2.0 - t);
        
        float shape = sin(n * 5.0 + t) * cos(n2 * 4.0 - t);
        shape = abs(shape);
        shape = smoothstep(0.2 + mouseInfluence * 0.3, 0.21, shape);
        
        vec3 col = vec3(0.5, 0.8, 0.9);
        if(i == 1.0) col = vec3(0.9, 0.4, 0.6);
        if(i == 2.0) col = vec3(0.3, 0.7, 0.4);
        
        color += shape * col;
    }
    
    color = mix(vec3(0.1, 0.1, 0.2), color, 1.0);
    color += noise(uv * 100.0) * 0.02;
    
    gl_FragColor = vec4(color, 1.0);
    
    #include <colorspace_fragment>
}