### Kaleidoscoped new land

Based on codepen.io/ge1doot/pen/vymqvp

```// Forked from "our new land" by ge1doot
// https://turtletoy.net/turtle/b2fdeed2d8

const mirrors = 8; //min=2 max=30 step=1

// You can find the Turtle API reference here: https://turtletoy.net/syntax
Canvas.setpenopacity(0.5);

// Global code will be evaluated once.
const turtle = new Kaleidoscope(0, 0, mirrors);
//const turtle = new Turtle();
turtle.penup();

class Noise {
// http://mrl.nyu.edu/~perlin/noise/
constructor(setup) {
this.p = new Uint8Array(512);
this.octaves = setup.octaves || 1;
const p = new Uint8Array(256);
for (let i = 0; i < 256; i++) p[i] = i;
for (let i = 255; i > 0; i--) {
const n = Math.floor((i + 1) * Math.random());
const q = p[i];
p[i] = p[n];
p[n] = q;
}
for (let i = 0; i < 512; i++) {
this.p[i] = p[i & 255];
}
}
lerp(t, a, b) {
return a + t * (b - a);
}
const v = (i & 1) === 0 ? x : y;
return (i & 2) === 0 ? -v : v;
}
noise2d(x2d, y2d) {
const X = Math.floor(x2d) & 255;
const Y = Math.floor(y2d) & 255;
const x = x2d - Math.floor(x2d);
const y = y2d - Math.floor(y2d);
const fx = (3 - 2 * x) * x * x;
const fy = (3 - 2 * y) * y * y;
const p0 = this.p[X] + Y;
const p1 = this.p[X + 1] + Y;
return this.lerp(
fy,
this.lerp(
fx,
),
this.lerp(
fx,
this.grad2d(this.p[p0 + 1], x, y - 1),
this.grad2d(this.p[p1 + 1], x - 1, y - 1)
)
);
}
noise(x, y) {
let e = 1,
k = 1,
s = 0;
for (let i = 0; i < this.octaves; ++i) {
e *= 0.5;
s += e * (1 + this.noise2d(k * x, k * y)) / 2;
k *= 2;
}
return s;
}
}
const perlin = new Noise({ octaves: 2 });
let y = 100;
const line = Array.from({ length: 200 }, () => 100);

// The walk function will be called until it returns false.
function walk(i) {
y -= 0.3;
turtle.goto(-100, y);
turtle.down();
let v = false;
for (let x = -100; x < 100; x++) {
let z = y +	0.25 * (
(2048 * perlin.noise(x * 0.02, 6 + y * 0.04)) & (16 + 32 + 0 + 128 + 256)
);
if (z > -100) v = true;
if (z > line[x]) z = line[x] - 0.01;
line[x] = z;
turtle.goto(x, z);
}
turtle.up();
return v;
}

function Kaleidoscope(x, y, mirrors = 4) {

function rot2(a) { return [Math.cos(a), -Math.sin(a), Math.sin(a), Math.cos(a)]; }
function trans2(m, a) { return [m[0]*a[0]+m[2]*a[1], m[1]*a[0]+m[3]*a[1]]; }
function segment_intersect2(a,b,d,c) {
const e=(c[1]-d[1])*(b[0]-a[0])-(c[0]-d[0])*(b[1]-a[1]);
if(0==e)return false;
c=((c[0]-d[0])*(a[1]-d[1])-(c[1]-d[1])*(a[0]-d[0]))/e;
d=((b[0]-a[0])*(a[1]-d[1])-(b[1]-a[1])*(a[0]-d[0]))/e;
return 0<=c&&1>=c&&0<=d&&1>=d?[a[0]+c*(b[0]-a[0]),a[1]+c*(b[1]-a[1])]:false;
}

function pointInTriangle(pt, ...v) {
const signFn = (p1, p2, p3) => (p1[0] - p3[0]) * (p2[1] - p3[1]) - (p2[0] - p3[0]) * (p1[1] - p3[1]);
const signs = v.map((v, i, arr) => signFn(pt, v, arr[(i+1)%arr.length]));
return !(signs.reduce((p, c) => p || c < 0, false) && signs.reduce((p, c) => p || c > 0, false));
}

class Kaleidoscope extends Turtle {
constructor(x, y, n = 4) {
super(x, y);

this.boundaries = [[0,0], [0, 1000], trans2(rot2(2*Math.PI/(n*2)), [0,1000])];

const rotations = Array.from({length: n}).map((v, i) => {
return (pt) => trans2(rot2(i * 2 * Math.PI / n), pt);
});
const mirrors = rotations.map(r => (pt) => trans2([-1, 0, 0, 1], r(pt)));

this.transforms = [...rotations, ...mirrors];

this.cur = this.pos();
this.curIn = this.inSegment(this.cur);

this.turtle = new Turtle(x, y);
}
inSegment(pt) {
return pointInTriangle(pt, ...this.boundaries);
}
goto(x, y) {
const target = Array.isArray(x)? x: [x, y];
const isDown = this.isdown();

const targetIn = this.turtle === undefined? false: this.inSegment(target);
if (isDown) {
(() => {
const bOne = segment_intersect2(this.cur, target, this.boundaries[0], this.boundaries[1]);
const bTwo = segment_intersect2(this.cur, target, this.boundaries[0], this.boundaries[2]);
debugger;
let from = this.cur;
let to = target;
if(!this.curIn && !targetIn) {
if(bOne === false && bTwo === false) return;
from = bOne;
to = bTwo;
} else if(!this.curIn) {
from = bOne === false? bTwo: bOne;
} else if(!targetIn) {
to = bOne === false? bTwo: bOne;
}
this.transforms.forEach(t => {
this.turtle.jump(t(from));
this.turtle.goto(t(to));
});
})();
}

this.cur = target;
this.curIn = targetIn

this.up();
super.goto(x, y);
if(isDown) this.down();
}
}
return new Kaleidoscope(x, y, mirrors)
}
```