game-of-life-3d

Result of working through the rust wasm book with some additions. Its a 3d version of game of life using the the (6,6,5,3) rule using periodic boundary conditions.

How to use from npm

You can view an example of using this with typescript here. The source for this is in the same github repo.

You first need to import the Universe, and Utils like:

import {Universe, Utils} from "game-of-life-3d";

Then you can instantiate an universe;

const universe = Universe.new(size, size, size);

// to create random live cells
universe.randomize();

// to reset the universe, removing all cells;
universe.reset();

// to go to the next state
universe.tick();

// you can also do several ticks ad once
universe.multi_tick(5);

// with the utils you can get all the cells as an Uint32 array for efficiency
const cells = Utils.getCellsFromUniverse(universe);

// to go though all the cells
for (let layer = 0; layer < universe.depth(); layer++) {
    for (let row = 0; row < universe.height(); row++) {
        for (let column = 0; column < universe.width(); column++) {
            const idx = Utils.getIndex(column, row, layer, universe.width(), universe.height());
            const isAlive = Utils.isCellAlive(idx, cells);
        }
    }
}

// after each tick, you can get the indexes of the changed cells
const changes = Utils.getChanges(universe);
// where changes[0] is an array of indexes of the new cells, and changes[1] an index of the removed cells

// you can toggle the status of a cell with
universe.toggle_cell(col, row, layer);

// then there are two gimmicks creating a 3d glider or pulser on the surrounding cells by setting there state
universe.glider(col, row, layer);
universe.pulse(col, row, layer);

How to build

Run wasm-pack build in the main folder.

Add to the generated game_of_life_3d.js:

const isBitSet = (number, bitPosition) => {
    return (number & (1 << bitPosition)) !== 0;
};

export class Utils {
    static getIndex (column, row, layer, width, height){
        return column + row * width + layer * width * height;
    };

    static getCellsFromUniverse (universe){
        const cellsPtr = universe.cells();
        universe.update_changes();
        return new Uint32Array(wasm.memory.buffer, cellsPtr, Math.ceil(universe.depth() * universe.width() * universe.height() / 32))
    };

    static getCellsAsBool (universe){
        const total = universe.depth() * universe.width() * universe.height();
        const result = new Array(total);
        const cells = this.getCellsFromUniverse(universe);
        for(let i = 0; i < total; i++){
            result[i] = this.isCellAlive(i, cells);
        }
        return result;
    };

    static isCellAlive (idx, cells) {
        const number = cells[Math.floor(idx / 32)];
        const bitPosition = idx % 32;
        return isBitSet(number, bitPosition);
    };

    static getArrayFromMemory (pointer, size){
        return new Uint32Array(wasm.memory.buffer, pointer, size);
    };

    static getChanges(universe){
        universe.update_changes();
        const births = Utils.getArrayFromMemory(universe.births(), universe.nr_of_births());
        const deaths = Utils.getArrayFromMemory(universe.deaths(), universe.nr_of_deaths());
        return [births, deaths];
    }
}

Add to the generated game_of_life_3d.d.ts:

export class Utils{
    static getIndex(column: number, row: number, layer: number, width: number, height: number): number;

    static getCellsFromUniverse(universe: Universe): Uint32Array;

    static getCellsAsBool(universe: Universe): boolean[];

    static isCellAlive(idx: number, cells: Uint32Array): boolean;

    static getArrayFromMemory(pointer: number, size: number): Uint32Array;

    static getChanges(universe: Universe): [Uint32Array, Uint32Array];
}

Then npm link in the created pkg folder Then npm link game-of-life-3d in the www folder

Then www directory first run npm install and then npm run start

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.