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` ````
```

` ````
body
margin: 0
background: #000
overflow: hidden
min-height: 100%
canvas
position: absolute
top: 50%
left: 50%
transform: translateX(-50%) translateY(-50%)
```

` ````
const hexRadius = 10;
const hexMargin = 1;
let hexHeight, hexWidth, columns, rows;
let hexagons = [];
function setup() {
hexWidth = hexRadius * 2;
hexHeight = Math.sqrt(3)*hexRadius;
columns = Math.ceil(window.innerWidth / (hexRadius * 3));
rows = Math.ceil(window.innerHeight / (hexHeight / 2)) + 1;
createCanvas((columns + 1/4) * (hexRadius * 3), (rows + 1) * (hexHeight / 2));
frameRate(5);
fill(255, 100);
stroke(255);
strokeWeight(5);
noStroke();
for (let x = 0; x < columns; x++) {
hexagons.push([]);
for (let y = 0; y < rows; y++) {
const active = Math.round(random()*0.6);
hexagons[x].push(new Hex(x, y, active));
}
}
// neighbouring needs to be done after they're all initialised
for (let x = 0; x < columns; x++) {
for (let y = 0; y < rows; y++) {
hexagons[x][y].initialiseNeighbours(x, y);
}
}
}
function draw() {
background(0);
for (let y = 0; y < rows; y++) {
for (let x = 0; x < columns; x++) {
let hex = hexagons[x][y];
hex.draw();
hex.checkActive();
}
}
update();
}
function update() {
for (let y = 0; y < rows; y++) {
for (let x = 0; x < columns; x++) {
let hex = hexagons[x][y];
hex.updateActive();
}
}
}
class Hex {
constructor(x, y, active) {
// establish grid position
this.pos = createVector(x, y);
// establish pixel position
this.pixelPos = createVector(0, 0);
this.pixelPos.x = hexWidth * (1.5 * x + 0.5 + y % 2 * 0.75);
this.pixelPos.y = hexHeight * (y * 0.5 + 0.5);
// establish state
this.active = active;
this.nextActive = false;
// establish neighbours
this.neighbours = [];
}
initialiseNeighbours(x, y) {
let n = [false, false, false, false, false, false];
const odd = y%2;
// above
if (y >= 2) {
n[0] = hexagons[x][y-2];
}
// top right
if (y >= 1) {
if (!odd || x < columns-1) {
n[1] = hexagons[x+odd][y-1];
}
}
// bottom right
if (y < rows-1) {
if (!odd || x < columns-1) {
n[2] = hexagons[x+odd][y+1];
}
}
// bottom
if (y < rows-2) {
n[3] = hexagons[x][y+2];
}
// bottom left
if (y < rows-1) {
if (odd || x >= 1) {
n[4] = hexagons[x-1+odd][y+1];
}
}
// top left
if (y >= 1) {
if (odd || x >= 1) {
n[5] = hexagons[x-1+odd][y-1];
}
}
this.neighbours = n;
}
updateActive() {
this.active = this.nextActive;
}
countActiveNeighbours() {
let activeNeighbours = 0;
for (let i = 0; i < 6; i++) {
if (this.neighbours[i] && this.neighbours[i].active) {
activeNeighbours++;
}
}
return activeNeighbours;
}
checkActive() {
let activeNeighbours = this.countActiveNeighbours();
if (this.active) {
// two or less it dies
if (activeNeighbours < 3) this.nextActive = false;
// five or more it dies
if (activeNeighbours > 4) this.nextActive = false;
} else {
// 2 it comes alive
if (activeNeighbours == 2) this.nextActive = true;
// 1 it comes alive 2% of the time
if (activeNeighbours == 1) {
if (Math.random() < 0.02) this.nextActive = true;
}
// 0 it comes alive 1% of the time
if (activeNeighbours == 0) {
if (Math.random() < 0.01) this.nextActive = true;
}
}
}
checkNeighbours() {
return true;
}
draw() {
if (this.active) {
let activeNeighbours = this.countActiveNeighbours();
fill(40+20*activeNeighbours, 40-10*activeNeighbours, 60+80*activeNeighbours);
} else {
fill(25);
}
push();
translate(this.pixelPos.x, this.pixelPos.y);
beginShape();
for (let i = 0; i < 6; i++) {
vertex((hexRadius-hexMargin/2)*cos(i*Math.PI/3), (hexRadius-hexMargin/2)*sin(i*Math.PI/3));
}
endShape(CLOSE);
pop();
}
}
```

999px

Also see: Tab Triggers