const margin = 10; //min=0 max=50 step=1
const dotCount = 2000; //min=100 max=5000 step=100
const rMin = .5; //min=.2 max=10 step=.1
const rMax = 1.3; //min=.2 max=10 step=.1
const plotterOpacity = .15; //min=.05 max=4 step=.01

// You can find the Turtle API reference here: https://turtletoy.net/syntax
Canvas.setpenopacity(-1);

// Global code will be evaluated once.
const turtle = new Turtle();
const polygons = new Polygons();

const minR = Math.min(rMin, rMax);
const maxR = Math.max(rMin, rMax);

const pts = getUniformDistributedPoints(dotCount, [margin-100, margin-100], [100-margin, 100-margin]);

// The walk function will be called until it returns false.
function walk(i) {
    const p = polygons.create();

    if(pts.length > 0) {
        const pt = pts.pop();
        const r = minR + Math.random()*(maxR - minR);
        p.addPoints(...Array.from({length: ((20 * r) | 0)}).map((v, i, arr) => [pt[0] + r * Math.sin(i*2*Math.PI/arr.length), pt[1]+r * Math.cos(i*2*Math.PI/arr.length)]));
        if(pt[0] < 0) p.addHatching(1, plotterOpacity);
        polygons.draw(turtle, p);
        
        return true;
    }
    
    p.addPoints([0, margin-100], [100-margin, margin-100], [100-margin, 100-margin], [0, 100-margin], [0, 100], [-100, 100], [-100, -100], [0, -100], [0, margin-100], [margin-100, margin-100], [margin-100, 100-margin], [0, 100-margin]);
    //p.addPoints([0, margin-100], [100-margin, margin-100], [100-margin, 100-margin], [0, 100-margin]);
    p.addHatching(1, plotterOpacity);
    polygons.draw(turtle, p);

    return false;
}

function getUniformDistributedPoints(n, leftTop, rightBottom, candidates = 10) {
    const width = rightBottom[0]-leftTop[0];
    const height = rightBottom[1]-leftTop[1];
    const maxDist = (width**2+height**2)**.5;
    
    const randomPoint = () => [Math.random()*width+leftTop[0],Math.random()*height+leftTop[1]];
    
    //We start with one randomly chosen point in our points list
    const pts = [randomPoint()];
    //While there are not yet a certain number of points chosen
    while(pts.length < dotCount) {
        //add a point to the list
        pts.push(
            //using [length] candidate points
            Array.apply(null,{length: candidates})
                 //which are random points
                 .map(i => randomPoint())
                 //then add a distance to that candidate
                 .map(i => [i[0], i[1], pts.map(j => [j[0], j[1], Math.hypot(i[0]-j[0], i[1]-j[1])])
                                           //so that it is the smallest distance from the
                                           //candidate to any of the already chosen points
                                           .reduce((prev, current) => (current[2] < prev[2])? current: prev, [0,0,maxDist])[2]
                    ])
                 //then pick the candidate that has the largest minimum distance from the group of candidates
                 .reduce((prev, current) => (current[2] > prev[2])? current: prev, [0,0,0])
                 //and remove the distance before promoting the candidate
                 .filter((i, k) => k < 2)
        );
    
    }
    return pts;
}

////////////////////////////////////////////////////////////////
// Polygon Clipping utility code - Created by Reinder Nijhoff 2019
// (Polygon binning by Lionel Lemarie 2021)
// https://turtletoy.net/turtle/a5befa1f8d
////////////////////////////////////////////////////////////////
function Polygons(){const t=[],s=25,e=Array.from({length:s**2},t=>[]),n=class{constructor(){this.cp=[],this.dp=[],this.aabb=[]}addPoints(...t){let s=1e5,e=-1e5,n=1e5,h=-1e5;(this.cp=[...this.cp,...t]).forEach(t=>{s=Math.min(s,t[0]),e=Math.max(e,t[0]),n=Math.min(n,t[1]),h=Math.max(h,t[1])}),this.aabb=[s,n,e,h]}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,s){const e=new n;e.cp.push([-1e5,-1e5],[1e5,-1e5],[1e5,1e5],[-1e5,1e5]);const h=Math.sin(t)*s,o=Math.cos(t)*s,a=200*Math.sin(t),i=200*Math.cos(t);for(let t=.5;t<150/s;t++)e.dp.push([h*t+i,o*t-a],[h*t-i,o*t+a]),e.dp.push([-h*t+i,-o*t-a],[-h*t-i,-o*t+a]);e.boolean(this,!1),this.dp=[...this.dp,...e.dp]}inside(t){let s=0;for(let e=0,n=this.cp.length;e<n;e++)this.segment_intersect(t,[.1,-1e3],this.cp[e],this.cp[(e+1)%n])&&s++;return 1&s}boolean(t,s=!0){const e=[];for(let n=0,h=this.dp.length;n<h;n+=2){const h=this.dp[n],o=this.dp[n+1],a=[];for(let s=0,e=t.cp.length;s<e;s++){const n=this.segment_intersect(h,o,t.cp[s],t.cp[(s+1)%e]);!1!==n&&a.push(n)}if(0===a.length)s===!t.inside(h)&&e.push(h,o);else{a.push(h,o);const n=o[0]-h[0],i=o[1]-h[1];a.sort((t,s)=>(t[0]-h[0])*n+(t[1]-h[1])*i-(s[0]-h[0])*n-(s[1]-h[1])*i);for(let n=0;n<a.length-1;n++)(a[n][0]-a[n+1][0])**2+(a[n][1]-a[n+1][1])**2>=.001&&s===!t.inside([(a[n][0]+a[n+1][0])/2,(a[n][1]+a[n+1][1])/2])&&e.push(a[n],a[n+1])}}return(this.dp=e).length>0}segment_intersect(t,s,e,n){const h=(n[1]-e[1])*(s[0]-t[0])-(n[0]-e[0])*(s[1]-t[1]);if(0===h)return!1;const o=((n[0]-e[0])*(t[1]-e[1])-(n[1]-e[1])*(t[0]-e[0]))/h,a=((s[0]-t[0])*(t[1]-e[1])-(s[1]-t[1])*(t[0]-e[0]))/h;return o>=0&&o<=1&&a>=0&&a<=1&&[t[0]+o*(s[0]-t[0]),t[1]+o*(s[1]-t[1])]}};return{list:()=>t,create:()=>new n,draw:(n,h,o=!0)=>{reducedPolygonList=function(n){const h={},o=200/s;for(var a=0;a<s;a++){const c=a*o-100,r=[0,c,200,c+o];if(!(n[3]<r[1]||n[1]>r[3]))for(var i=0;i<s;i++){const c=i*o-100;r[0]=c,r[2]=c+o,n[0]>r[2]||n[2]<r[0]||e[i+a*s].forEach(s=>{const e=t[s];n[3]<e.aabb[1]||n[1]>e.aabb[3]||n[0]>e.aabb[2]||n[2]<e.aabb[0]||(h[s]=1)})}}return Array.from(Object.keys(h),s=>t[s])}(h.aabb);for(let t=0;t<reducedPolygonList.length&&h.boolean(reducedPolygonList[t]);t++);h.draw(n),o&&function(n){t.push(n);const h=t.length-1,o=200/s;e.forEach((t,e)=>{const a=e%s*o-100,i=(e/s|0)*o-100,c=[a,i,a+o,i+o];c[3]<n.aabb[1]||c[1]>n.aabb[3]||c[0]>n.aabb[2]||c[2]<n.aabb[0]||t.push(h)})}(h)}}}