// LL 2021

// Inspired by https://twitter.com/generativehut/status/1393499529467600896

const iterations = 200; // min=1 max=1000 step=1
const inner_size = 10; // min=1 max=100 step=1
const point_count = 300; // min=10 max=1000 step=1
const loop_count = 20;  // min=0 max=20 step=1
const grow_fract = -50; // min=-101 max=1000 step=1
const spread = 1; // min=0 max=100 step=1
const mult = 2; // min=1 max=20 step=.01
const use_max = 1; // min=0 max=1 step=1 (No,Yes)
const seed = 0; // min=0 max=100 step=1
const style = 0; // min=0 max=1 step=1 (Lines (fast),Polygons (slow))

Canvas.setpenopacity(1);

const turtle = new Turtle();

function walk(i) {
    if (i==0) {
        rng = new RNG(seed);
        polygons = new Polygons();
        circle = new Circle(inner_size, point_count);
        circle_max = circle.dup();
    }
    
    const a = i * Math.PI/2 / Math.max(1, iterations-1);
    const d = 0; //1;

    //if (i==1)    
    circle.draw(a, d, circle_max);

    const more_to_draw = circle.mutate();
    if (!more_to_draw) return false;

    circle_max.recordMax(circle);
    
    //sleep(100);
    
    return i + 1 < iterations;
}

class Circle {
    constructor(size, count, points=undefined) {
        this.size = size;
        this.count = count;
        
        if (points === undefined) {        
            this.points = [];
            const astep = Math.PI * 2 / this.count;
            for (var i=0, a=0; i<this.count; i++, a+=astep) {
                const x = size * Math.cos(a);
                const y = size * Math.sin(a);
                this.points.push(x); // ,y);
                this.points.push(y);
            }
        } else {
            this.points = [...points];
        }
    }
    
    dup() {
        return new Circle(this.size, this.count, this.points);
    }
    
    recordMax(circle) {
        for (var i=0; i<this.points.length && i<circle.points.length; i++) {
            this.points[i] = smax(this.points[i], circle.points[i]);
        }
    }
    
    draw(a, d, circle_max) {
        const points = [];
        for (var i=0; i<this.count && i<circle_max.count; i++) {
            var x = this.points[i*2+0];
            var y = this.points[i*2+1];
            if (use_max) {
                x = smax(x, circle_max.points[i*2+0]);
                y = smax(y, circle_max.points[i*2+1]);
            }
            points.push([x, y]);
        }
        drawPoints(points, a, d);
    }
    
    mutate() {
        var more_to_draw = loop_count < 1;
        
        const grow = 1 + grow_fract / 1000;
        for (var i = 0; i < this.points.length; i++) {
            this.points[i] *= grow;
        }
        
        for (var loop = 0; loop < loop_count; loop++) {
            const index = (this.count * rng.nextFloat()) | 0;
            this.points[index * 2 + 0] *= mult;
            this.points[index * 2 + 1] *= mult;
        
            const new_points = [...this.points];
            for (var i = 0; i < this.count; i++) {
                const this_len = Math.hypot(this.points[i * 2], this.points[i * 2 + 1]);
                var total_len = 0;
                var len_count = 0;
                for (var j=-spread; j<=spread; j++, len_count++) {
                    const ii = (i + this.points.length + j) % (this.count);
                    total_len += Math.hypot(this.points[ii * 2], this.points[ii * 2 + 1]);;
                }
                const nlen = total_len / len_count;
                const factor = nlen / this_len;
                new_points[i*2+0] *= factor;
                new_points[i*2+1] *= factor;

                more_to_draw |= Math.abs(new_points[i*2]) < 100 && Math.abs(new_points[i*2+1]) < 100 && Math.abs(new_points[i*2]) > 1 && Math.abs(new_points[i*2+1]) > 1;
            }
            this.points = new_points;
        }

        return more_to_draw;
    }
}

function smax(v1, v2) {
    const v = Math.max(Math.abs(v1), Math.abs(v2)) * Math.sign(v1);
    return v;
}

function sleep(ms) { start=Date.now(); while (Date.now()-start<ms); }

// Random with seed
function RNG(t){return new class{constructor(t){this.m=2147483648,this.a=1103515245,this.c=12345,this.state=t||Math.floor(Math.random()*(this.m-1))}nextFloat(){return this.state=(this.a*this.state+this.c)%this.m,this.state/(this.m-1)}}(t)}

function drawPoints(points, hatching_angle = 0, hatching_distance = 0) {
    if (style == 0) {
        turtle.jump(points[points.length-1]);
        points.forEach(p=>turtle.goto(p));
    } else {
        const p1 = polygons.create();
        p1.addPoints(...points);
        if (hatching_distance) p1.addHatching(hatching_angle, hatching_distance);
        p1.addOutline();
        polygons.draw(turtle, p1, true);
    }
}

////////////////////////////////////////////////////////////////
// Polygon Clipping utility code - Created by Reinder Nijhoff 2019
// https://turtletoy.net/turtle/a5befa1f8d
////////////////////////////////////////////////////////////////
function Polygons(){const t=[],s=class{constructor(){this.cp=[],this.dp=[],this.aabb=[]}addPoints(...t){let s=1e5,e=-1e5,h=1e5,i=-1e5;(this.cp=[...this.cp,...t]).forEach(t=>{s=Math.min(s,t[0]),e=Math.max(e,t[0]),h=Math.min(h,t[1]),i=Math.max(i,t[1])}),this.aabb=[(s+e)/2,(h+i)/2,(e-s)/2,(i-h)/2]}addSegments(...t){t.forEach(t=>this.dp.push(t))}addOutline(){for(let t=0,s=this.cp.length;t<s;t++)this.dp.push(this.cp[t],this.cp[(t+1)%s])}draw(t){for(let s=0,e=this.dp.length;s<e;s+=2)t.jump(this.dp[s]),t.goto(this.dp[s+1])}addHatching(t,e){const h=new s;h.cp.push([-1e5,-1e5],[1e5,-1e5],[1e5,1e5],[-1e5,1e5]);const i=Math.sin(t)*e,n=Math.cos(t)*e,a=200*Math.sin(t),p=200*Math.cos(t);for(let t=.5;t<150/e;t++)h.dp.push([i*t+p,n*t-a],[i*t-p,n*t+a]),h.dp.push([-i*t+p,-n*t-a],[-i*t-p,-n*t+a]);h.boolean(this,!1),this.dp=[...this.dp,...h.dp]}inside(t){let s=0;for(let e=0,h=this.cp.length;e<h;e++)this.segment_intersect(t,[.1,-1e3],this.cp[e],this.cp[(e+1)%h])&&s++;return 1&s}boolean(t,s=!0){if(Math.abs(this.aabb[0]-t.aabb[0])-(t.aabb[2]+this.aabb[2])>=0&&Math.abs(this.aabb[1]-t.aabb[1])-(t.aabb[3]+this.aabb[3])>=0)return this.dp.length>0;const e=[];for(let h=0,i=this.dp.length;h<i;h+=2){const i=this.dp[h],n=this.dp[h+1],a=[];for(let s=0,e=t.cp.length;s<e;s++){const h=this.segment_intersect(i,n,t.cp[s],t.cp[(s+1)%e]);!1!==h&&a.push(h)}if(0===a.length)s===!t.inside(i)&&e.push(i,n);else{a.push(i,n);const h=n[0]-i[0],p=n[1]-i[1];a.sort((t,s)=>(t[0]-i[0])*h+(t[1]-i[1])*p-(s[0]-i[0])*h-(s[1]-i[1])*p);for(let h=0;h<a.length-1;h++)(a[h][0]-a[h+1][0])**2+(a[h][1]-a[h+1][1])**2>=.001&&s===!t.inside([(a[h][0]+a[h+1][0])/2,(a[h][1]+a[h+1][1])/2])&&e.push(a[h],a[h+1])}}return(this.dp=e).length>0}segment_intersect(t,s,e,h){const i=(h[1]-e[1])*(s[0]-t[0])-(h[0]-e[0])*(s[1]-t[1]);if(0===i)return!1;const n=((h[0]-e[0])*(t[1]-e[1])-(h[1]-e[1])*(t[0]-e[0]))/i,a=((s[0]-t[0])*(t[1]-e[1])-(s[1]-t[1])*(t[0]-e[0]))/i;return n>=0&&n<=1&&a>=0&&a<=1&&[t[0]+n*(s[0]-t[0]),t[1]+n*(s[1]-t[1])]}};return{list:()=>t,create:()=>new s,draw:(s,e,h=!0)=>{for(let s=0;s<t.length&&e.boolean(t[s]);s++);e.draw(s),h&&t.push(e)}}}