easel3d/tutorial/wasm-game-of-life/www/index.js

import { Universe, Cell, View3d, Color } from "wasm-game-of-life";
import { memory } from "wasm-game-of-life/wasm_game_of_life_bg";

// 3D canvas stuff
const view3d = View3d.new(151, 151);

const view3d_canvas  = document.getElementById("view3d");
view3d_canvas.width  = view3d.width();
view3d_canvas.height = view3d.height();
const view3d_ctx     = view3d_canvas.getContext('2d');

const view3d_renderLoop = () => {
    view3d.update();
    drawView3d();

    requestAnimationFrame(view3d_renderLoop);
}

const drawView3d = () => {
    const view3d_imagePtr = view3d.image();
    const view3d_image    = new ImageData(
        new Uint8ClampedArray( memory.buffer
                             , view3d.image()
                             , view3d.width() * view3d.height() * 4 )
        , view3d.width()
        , view3d.height() );

    view3d_ctx.putImageData(view3d_image, 0, 0);
}

// game of life stuff
const CELL_SIZE   = 5; // px
const GRID_COLOR  = "#CCCCCC";
const DEAD_COLOR  = "#FFFFFF";
const ALIVE_COLOR = "#000000";

const universe = Universe.new();
const    width = universe.width();
const   height = universe.height();

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');

const renderLoop = () => {
    universe.tick();

    drawGrid();
    drawCells();

    requestAnimationFrame(renderLoop);
};

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();
};

const getIndex = (row, col) => {
    return row * width + col;
};

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 < height; 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();
};

// start everything ...
//drawGrid();
//drawCells();
//requestAnimationFrame(renderLoop);

view3d.update();
drawView3d();
requestAnimationFrame(view3d_renderLoop);