game-of-life/www/index.js

237 lines
5.7 KiB
JavaScript

import { Universe, Cell, init } from "gameoflife";
import { memory } from "gameoflife/gameoflife_bg.wasm";
// let PLAY = true;
// let PLAY = false;
init();
const randSlider = document.getElementById("randThreshold");
const randSliderLabel = document.getElementById("randThreshold-label");
const CELL_SIZE = 4; // px
const GRID_COLOR = "#BBBBBB";
const DEAD_COLOR = "#FFFFFF";
const ALIVE_COLOR = "#FF55AA";
let universe = Universe.new(100, 100, randSlider.value, new Date().getTime() / 1000);
let width = universe.width();
let height = universe.height();
let play = false;
const canvas = document.getElementById("game-of-life-canvas");
canvas.height = (CELL_SIZE + 1) * height + 1;
canvas.width = (CELL_SIZE + 1) * width + 1;
const ctx = canvas.getContext('2d');
/**
* Draw grid onto canvas prior to painting cells
*/
const drawGrid = () => {
ctx.beginPath();
ctx.strokeStyle = GRID_COLOR;
// Vertical lines.
for (let i = 0; i <= width; i++) {
ctx.moveTo(i * (CELL_SIZE + 1) + 1, 0);
ctx.lineTo(i * (CELL_SIZE + 1) + 1, (CELL_SIZE + 1) * height + 1);
}
// Horizontal lines.
for (let j = 0; j <= height; j++) {
ctx.moveTo(0, j * (CELL_SIZE + 1) + 1);
ctx.lineTo((CELL_SIZE + 1) * width + 1, j * (CELL_SIZE + 1) + 1);
}
ctx.stroke();
};
/**
* Get linear index from row and column indices
* @param {*} row Row index
* @param {*} column Column index
* @returns Linear index
*/
const getIndex = (row, column) => {
return row * width + column;
};
/**
* Paint alive cells onto grid
*/
const drawCells = () => {
const cellsPtr = universe.cells();
const cells = new Uint8Array(memory.buffer, cellsPtr, width * height);
ctx.beginPath();
for (let row = 0; row < height; row++) {
for (let col = 0; col < width; col++) {
const idx = getIndex(row, col);
ctx.fillStyle = cells[idx] === Cell.Dead
? DEAD_COLOR
: ALIVE_COLOR;
ctx.fillRect(
col * (CELL_SIZE + 1) + 1,
row * (CELL_SIZE + 1) + 1,
CELL_SIZE,
CELL_SIZE
);
}
}
ctx.stroke();
};
/**
* Single frame/step of game, tick universe, refresh UI
*/
const renderSingle = () => {
// fps.render(); //new
universe.tick();
drawGrid();
drawCells();
}
/**
* Start interval timer to periodically iterate frames
*/
const start = () => {
if(loop != null) clearInterval(loop);
loop = setInterval(renderSingle, frameInterval);
}
/**
* Clear interval timer to stop animation loop
*/
const stop = () => {
if(loop != null) clearInterval(loop);
loop = null;
}
var frameInterval = 50;
// var loop = setInterval(renderSingle, frameInterval);
var loop = null;
// SLIDERS
const frameSlider = document.getElementById("frameRate");
const frameSliderLabel = document.getElementById("frameRate-label");
/**
* Handler for frame interval slider change, stop, change interval, start
*/
const onFrameSlider = () => {
stop();
frameInterval = frameSlider.value;
frameSliderLabel.innerHTML = `Frame Interval: ${frameSlider.value}ms`;
if(play) start();
}
frameSlider.onchange = onFrameSlider;
frameSlider.value = 100;
/**
* Handler for random threshold slider change, get a new universe with new threshold
*/
const onRandSlider = () => {
stop();
universe = Universe.new(width, height, randSlider.value, new Date().getTime() / 1000);
refreshCanvas();
randSliderLabel.innerHTML = `Random Threshold: ${randSlider.value}%`;
if(play) start();
}
randSlider.onchange = onRandSlider;
randSlider.value = 50;
/**
* Refresh existing canvas, calculate dimensions and draw
*/
const refreshCanvas = () => {
canvas.width = (CELL_SIZE + 1) * width + 1;
canvas.height = (CELL_SIZE + 1) * height + 1;
drawGrid();
drawCells();
}
// INPUT BOXES
const widthBox = document.getElementById("width");
/**
* Handler for width input box change, get a new universe of given size
*/
const onWidth = () => {
// PLAY = false;
width = widthBox.value;
universe = Universe.new(width, height, randSlider.value, new Date().getTime() / 1000);
refreshCanvas();
// PLAY = true;
// requestAnimationFrame(renderLoop);
}
widthBox.onchange = onWidth;
widthBox.value = 100;
const heightBox = document.getElementById("height");
/**
* Handler for height input box change, get a new universe of given size
*/
const onHeight = () => {
// PLAY = false;
height = heightBox.value;
universe = Universe.new(width, height, randSlider.value, new Date().getTime() / 1000);
refreshCanvas();
// PLAY = true;
// requestAnimationFrame(renderLoop);
}
heightBox.onchange = onHeight;
heightBox.value = 100;
// BUTTONS
/**
* Click handler for step button, make single move
*/
const onPlay = () => {
play = !play;
// console.log("play: " + play);
if(play) {
playButton.classList.remove("btn-success");
playButton.classList.add("btn-danger");
playButton.innerText = "Stop";
start();
}else {
playButton.classList.add("btn-success");
playButton.classList.remove("btn-danger");
playButton.innerText = "Play";
stop();
}
}
const playButton = document.getElementById("play");
playButton.onclick = onPlay;
/**
* Click handler for step button, make single move
*/
const onStep = () => {
console.log("stepping");
renderSingle();
}
document.getElementById("step").onclick = onStep;
/**
* Click handler for reset button, generate a new universe and refresh the canvas
*/
const onReset = () => {
universe = Universe.new(width, height, randSlider.value, new Date().getTime() / 1000);
refreshCanvas();
}
document.getElementById("reset").onclick = onReset;
drawGrid();
drawCells();