aperiodic-monotile-reference/script.js

504 lines
14 KiB
JavaScript

// derived from https://cs.uwaterloo.ca/~csk/spectre/spectre.js
const {PI, cos, sin} = Math;
function radians(degrees) {
return degrees * PI / 180;
}
let num_pieces = 0;
class Point {
constructor(x,y) {
this.x = x;
this.y = y;
}
add(q) {
return { x : this.x + q.x, y : this.y + q.y };
}
sub(q) {
return { x : this.x - q.x, y : this.y - q.y };
}
frame(p, q, a, b) {
return{ x : this.x + a*p.x + b*q.x, y : this.y + a*p.y + b*q.y };
}
}
class Matrix {
constructor(mat) {
this.mat = mat;
}
determinant() {
const T = this.mat;
const det = T[0]*T[4] - T[1]*T[3];
}
inverse() {
const T = this.mat;
const det = this.determinant();
return new Matrix([
T[4]/det,
-T[1]/det,
(T[1]*T[5]-T[2]*T[4])/det,
-T[3]/det,
T[0]/det,
(T[2]*T[3]-T[0]*T[5])/det
]);
}
mul(other) {
const A = this.mat;
const B = other.mat;
return new Matrix([
A[0]*B[0] + A[1]*B[3],
A[0]*B[1] + A[1]*B[4],
A[0]*B[2] + A[1]*B[5] + A[2],
A[3]*B[0] + A[4]*B[3],
A[3]*B[1] + A[4]*B[4],
A[3]*B[2] + A[4]*B[5] + A[5]
]);
}
// Rotation matrix
static rotation(ang) {
const c = cos(ang);
const s = sin(ang);
return new Matrix([c, -s, 0, s, c, 0]);
}
static scale(x,y) {
return new Matrix([x,0,0,0,y,0]);
}
static translate(tx, ty) {
return new Matrix([1, 0, tx, 0, 1, ty]);
}
// Translation matrix moving p to q
static translateTo(p, q) {
return Matrix.translate(q.x - p.x, q.y - p.y);
}
transform(P) {
const M = this.mat;
return new Point(M[0]*P.x + M[1]*P.y + M[2], M[3]*P.x + M[4]*P.y + M[5]);
}
}
const ident = new Matrix([1,0,0,0,1,0]);
const spectre = [
new Point(0, 0),
new Point(1.0, 0.0),
new Point(1.5, -0.8660254037844386),
new Point(2.366025403784439, -0.36602540378443865),
new Point(2.366025403784439, 0.6339745962155614),
new Point(3.366025403784439, 0.6339745962155614),
new Point(3.866025403784439, 1.5),
new Point(3.0, 2.0),
new Point(2.133974596215561, 1.5),
new Point(1.6339745962155614, 2.3660254037844393),
new Point(0.6339745962155614, 2.3660254037844393),
new Point(-0.3660254037844386, 2.3660254037844393),
new Point(-0.866025403784439, 1.5),
new Point(0.0, 1.0)
];
const base_quad = [spectre[3], spectre[5], spectre[7], spectre[11]];
function getsvg(event) {
let t = event.target;
while(t && t.tagName.toLowerCase()!='svg') {
t = t.parentElement;
}
return t;
}
function getcoords(event) {
const t = getsvg(event);
if(!t) {
return;
}
const point = t.createSVGPoint()
point.x = event.clientX
point.y = event.clientY
const position = point.matrixTransform(t.getScreenCTM().inverse())
return position;
}
class Tile {
constructor(pts, quad) {
this.pts = pts;
this.quad = quad;
this.pts = [pts[pts.length-1]];
for(const p of pts) {
const prev = this.pts[this.pts.length-1];
const v = p.sub(prev);
const w = new Point(-v.y, v.x);
this.pts.push(prev.frame(v, w, 0.5, -0.3));
this.pts.push(prev.frame(v, w, 0.5, 0.3));
this.pts.push(p);
}
}
streamSVG(S, stream) {
const tpts = this.pts.map(p => S.transform(p));
const [a,c,e,b,d,f] = S.mat;
const matS = [a,b,c,d,e,f].map(p=>p.toFixed(3));
num_pieces += 1;
stream.push(`<g class="tile">
<use href="#spectre" transform="matrix(${matS.join(',')}) "/>
<text font-size="0.5" dominant-baseline="middle" text-anchor="middle" transform="matrix(${matS.join(',')}) translate(1 1.6)">${num_pieces}</text>
<text font-size="1" dominant-baseline="middle" text-anchor="middle" transform="matrix(${matS.join(',')}) translate(1 1)">↑</text>
</g>`);
}
}
class Metatile {
constructor() {
this.geoms = [];
this.quad = [];
}
addChild(g, T) {
this.geoms.push({ geom : g, xform: T });
}
streamSVG(S, stream) {
for(let g of this.geoms) {
g.geom.streamSVG(S.mul(g.xform), stream);
}
}
}
function tiles(level, label) {
let quad;
let out = [];
let transform;
if(level == 0) {
transform = ident;
quad = base_quad;
switch(label) {
case 'Delta':
case 'Theta':
case 'Lambda':
case 'Xi':
case 'Pi':
case 'Sigma':
case 'Phi':
case 'Psi':
out.push(ident);
case 'Gamma':
const mystic = new Metatile();
out.push(ident);
out.push(Matrix.translate(spectre[8].x, spectre[8].y).mul(Matrix.rotation(PI / 6)));
}
} else {
/*
* Each of the subtiles is identical, but rotated and translated.
*
* Produce transformation matrices Ts for each of the subtiles: they're formed by rotating the quad and then matching up a pair of points.
*
* The whole thing is then reflected.
*
* The layout of subtiles depends on the larger tile.
*
*/
const labels = [
'Delta',
'Theta',
'Lambda',
'Xi',
'Pi',
'Sigma',
'Phi',
'Psi'
];
const sublevels = Object.fromEntries(labels.map(label => tiles(level-1, label)));
const subquad = sublevels['Delta'].quad;
const reflection = Matrix.scale(-1,1);
// How to get from each subtile to the next.
const t_rules = [
[60, 3, 1],
[0, 2, 0],
[60, 3, 1],
[60, 3, 1],
[0, 2, 0],
[60, 3, 1],
[-120, 3, 3]
];
let Ts = [ident];
let total_ang = 0;
let rot = ident;
let tquad = [...subquad];
for(const [ang,from,to] of t_rules) {
total_ang += ang;
if(ang != 0) {
rot = Matrix.rotation(radians(total_ang));
tquad = subquad.map(q => rot.transform(q));
}
const ttt = Matrix.translateTo(tquad[to], Ts[Ts.length-1].transform(subquad[from]));
Ts.push(ttt.mul(rot));
}
Ts = Ts.map(t => mul(reflection, t));
// Now build the actual supertiles, labelling appropriately.
const super_rules = {
'Gamma' : ['Pi','Delta','null','Theta','Sigma','Xi','Phi','Gamma'],
'Delta' : ['Xi','Delta','Xi','Phi','Sigma','Pi','Phi','Gamma'],
'Theta' : ['Psi','Delta','Pi','Phi','Sigma','Pi','Phi','Gamma'],
'Lambda' : ['Psi','Delta','Xi','Phi','Sigma','Pi','Phi','Gamma'],
'Xi' : ['Psi','Delta','Pi','Phi','Sigma','Psi','Phi','Gamma'],
'Pi' : ['Psi','Delta','Xi','Phi','Sigma','Psi','Phi','Gamma'],
'Sigma' : ['Xi','Delta','Xi','Phi','Sigma','Pi','Lambda','Gamma'],
'Phi' : ['Psi','Delta','Psi','Phi','Sigma','Pi','Phi','Gamma'],
'Psi' : ['Psi','Delta','Psi','Phi','Sigma','Psi','Phi','Gamma']
};
const super_quad = [
Ts[6].transform(subquad[2]),
Ts[5].transform(subquad[1]),
Ts[3].transform(subquad[2]),
Ts[0].transform(subquad[1]) ];
}
return {quad, tiles: out};
}
let last_num_iterations;
function get_settings() {
return Object.fromEntries(
Array.from(document.querySelectorAll('input,textarea')).map(i => [i.id, i.type=='number' ? i.valueAsNumber : i.value])
);
}
class Builder {
constructor(settings) {
this.settings = settings;
}
build() {
const {settings} = this;
num_pieces = 0;
let sys = this.buildSpectreBase();
for(let i=0;i<settings.num_iterations;i++) {
sys = this.buildSupertiles(sys);
}
sys = sys['Delta'];
this.sys = sys;
}
buildSpectreBase() {
const ret = {};
for(let lab of ['Delta', 'Theta', 'Lambda', 'Xi',
'Pi', 'Sigma', 'Phi', 'Psi']) {
ret[lab] = new Tile(spectre, base_quad, lab);
}
const mystic = new Metatile();
mystic.addChild(new Tile(spectre, base_quad, 'Gamma1'), ident);
mystic.addChild(new Tile(spectre, base_quad, 'Gamma2'),
Matrix.translate(spectre[8].x, spectre[8].y).mul(Matrix.rotation(PI / 6)));
mystic.quad = base_quad;
ret['Gamma'] = mystic;
return ret;
}
buildSupertiles(sys) {
// First, use any of the nine-unit tiles in sys to obtain
// a list of transformation matrices for placing tiles within
// supertiles.
const quad = sys['Delta'].quad;
const R = new Matrix([-1,0,0,0,1,0]);
const t_rules = [
[60, 3, 1], [0, 2, 0], [60, 3, 1], [60, 3, 1],
[0, 2, 0], [60, 3, 1], [-120, 3, 3] ];
const Ts = [ident];
let total_ang = 0;
let rot = ident;
const tquad = [...quad];
for(const [ang,from,to] of t_rules) {
total_ang += ang;
if(ang != 0) {
rot = Matrix.rotation(radians(total_ang));
for(let i = 0; i < 4; ++i) {
tquad[i] = rot.transform(quad[i]);
}
}
const ttt = Matrix.translateTo(tquad[to],
Ts[Ts.length-1].transform(quad[from]));
Ts.push(ttt.mul(rot));
}
for(let idx = 0; idx < Ts.length; ++idx) {
Ts[idx] = R.mul(Ts[idx]);
}
// Now build the actual supertiles, labelling appropriately.
const super_rules = {
'Gamma' : ['Pi','Delta','null','Theta','Sigma','Xi','Phi','Gamma'],
'Delta' : ['Xi','Delta','Xi','Phi','Sigma','Pi','Phi','Gamma'],
'Theta' : ['Psi','Delta','Pi','Phi','Sigma','Pi','Phi','Gamma'],
'Lambda' : ['Psi','Delta','Xi','Phi','Sigma','Pi','Phi','Gamma'],
'Xi' : ['Psi','Delta','Pi','Phi','Sigma','Psi','Phi','Gamma'],
'Pi' : ['Psi','Delta','Xi','Phi','Sigma','Psi','Phi','Gamma'],
'Sigma' : ['Xi','Delta','Xi','Phi','Sigma','Pi','Lambda','Gamma'],
'Phi' : ['Psi','Delta','Psi','Phi','Sigma','Pi','Phi','Gamma'],
'Psi' : ['Psi','Delta','Psi','Phi','Sigma','Psi','Phi','Gamma'] };
const super_quad = [
Ts[6].transform(quad[2]),
Ts[5].transform(quad[1]),
Ts[3].transform(quad[2]),
Ts[0].transform(quad[1]) ];
const ret = {};
for(const [lab, subs] of Object.entries(super_rules)) {
const sup = new Metatile();
for(let idx = 0; idx < 8; ++idx) {
if(subs[idx] == 'null') {
continue;
}
sup.addChild(sys[subs[idx]], Ts[idx]);
}
sup.quad = super_quad;
ret[lab] = sup;
}
return ret;
}
draw() {
const {sys} = this;
const drawing = [];
const svg = document.querySelector('svg');
const board = svg.querySelector('#board');
board.innerHTML = '';
const R = new Matrix([-1,0,0,0,1,0]);
const m = this.settings.num_iterations % 2 == 0 ? ident : R;
sys.streamSVG(m, drawing);
board.innerHTML = drawing.join(' ');
const viewbox = svg.getBoundingClientRect();
function visit(g, t) {
for(let c of g.children) {
visit(c, t+Math.random()*10-5);
}
if(g.tagName=='path') {
const b = g.getBoundingClientRect();
const x = (b.x - viewbox.x) / viewbox.width;
const y = (b.y - viewbox.y) / viewbox.height;
g.style.color = '#ccc';
}
}
visit(board,50);
svg.addEventListener('click', e => {
if(!last_click) {
return;
}
let tile = e.target;
while(tile && !tile.classList.contains('tile')) {
tile = tile.parentElement;
}
if(!tile) {
return;
}
for(let el of svg.querySelectorAll('.highlight')) {
el.classList.remove('highlight');
}
tile.classList.add('highlight');
});
}
}
function update_display() {
const settings = get_settings();
const svg = document.querySelector('svg');
svg.setAttribute('viewBox',`${-settings.scale/2} ${-settings.scale/2} ${settings.scale} ${settings.scale}`);
const mx = spectre.map(p=>p.x).reduce((a,b)=>a+b)/spectre.length;
const my = spectre.map(p=>p.y).reduce((a,b)=>a+b)/spectre.length;
document.getElementById('spectre').setAttribute('transform',`translate(${mx},${my}) translate(${-mx},${-my})`);
if(settings.num_iterations != last_num_iterations) {
const builder = new Builder(settings);
builder.build();
builder.draw();
last_num_iterations = settings.num_iterations;
}
}
for(let i of document.querySelectorAll('input')) {
i.addEventListener('input', update_display);
i.addEventListener('change', update_display)
}
update_display();
let opos;
let dragging;
let pan = {x:0, y:0};
let npan = pan;
let last_click = false;
const svg = document.querySelector('svg');
svg.addEventListener('pointerdown', e => {
opos = getcoords(e);
dragging = true;
});
svg.addEventListener('pointermove', e => {
if(!dragging) {
return;
}
const pos = getcoords(e);
npan = {x: pan.x + pos.x - opos.x, y: pan.y + pos.y - opos.y};
document.getElementById('board').setAttribute('transform', `translate(${npan.x} ${npan.y})`);
});
svg.addEventListener('pointerup', e => {
dragging = false;
const [dx,dy] = [npan.x - pan.x, npan.y - pan.y];
const d = Math.sqrt(dx*dx + dy*dy);
last_click = d < 0.5;
pan = npan;
});