@scale-at/expo-pixi

expo-pixi

Tools to use Pixi.js in Expo!

To get started: yarn add expo-pixi in your Expo project and import it with import ExpoPixi from 'expo-pixi';.

Side-Effects

To use Pixi.js with Expo & React Native you will want to import a modified version of Pixi.js like so:

// ✅
import { PIXI } from 'expo-pixi';

// ❌
import * as PIXI from 'pixi.js';

Now you can create a new Application the way you would on the web, but be sure to pass in a WebGLRenderingContext.

// ✅
const app = new PIXI.Application({ context });

// ❌
const app = ExpoPIXI.application({ context });

Finally, because of the way React Native currently works you must load in assets asynchronously.

/*
 * Accepts: 
 * - Expo.Asset: import { Asset } from 'expo-asset'; Asset.fromModule( ... );
 * - URL (with file extension): 'http://i.imgur.com/uwrbErh.png'
 * - Static Resource: require('./icon.png')
 */

// ✅
const sprite = await PIXI.Sprite.fromExpoAsync('http://i.imgur.com/uwrbErh.png');

// OR 

const texture = await PIXI.Texture.fromExpoAsync('http://i.imgur.com/uwrbErh.png');

// ❌
const sprite = await ExpoPIXI.spriteAsync('http://i.imgur.com/uwrbErh.png');

// OR 

const texture = await ExpoPIXI.textureAsync('http://i.imgur.com/uwrbErh.png');

Using web syntax will return a Promise, and throw a warning. It's bad practice, but if the asset is loaded already, this will work without throwing a warning.

const sprite = await PIXI.Sprite.from(require('./icon.png'));

// > console.warning(PIXI.Sprite.from(asset: ${typeof asset}) is not supported. Returning a Promise!);

// OR 

const texture = await PIXI.Texture.from(require('./icon.png'));

// > console.warning(PIXI.Texture.from(asset: ${typeof asset}) is not supported. Returning a Promise!);

Functions

ExpoPixi.application(props): PIXI.Application

Deprecated: Use new PIXI.Application({ context });

A helper function to create a PIXI.Application from a WebGL context. EXGL knows to end a frame when the function: endFrameEXP is called on the GL context.

context is the only required prop.

Learn more about PIXI.Application props

ExpoPixi.textureAsync(resource: any): Promise

Deprecated: Use PIXI.Texture.fromExpoAsync(resource);

ExpoPixi.spriteAsync(resource: any): Promise

Deprecated: Use PIXI.Sprite.fromExpoAsync(resource);

a helper function to resolve the asset passed in. textureAsync accepts:

• localUri: string | ex: "file://some/path/image.png"
• static resource: number | ex: require('./image.png')
• remote url: string | ex: "https://www.something.com/image.png"
• asset-library: string (iOS CameraRoll) | ex: "asset-library://some/path/image.png"
• Expo Asset: Expo.Asset | learn more: https://docs.expo.io/versions/latest/guides/assets.html

You cannot send in relative string paths as Metro Bundler looks for static resources.

---

ExpoPixi.sprite({ localUri: string, width: number, height: number }): PIXI.Sprite

Deprecated: Use PIXI.Sprite.from(resource);

ExpoPixi.texture({ localUri: string, width: number, height: number }): PIXI.Texture

Deprecated: Use PIXI.Texture.from(resource);

Pixi.js does a type check so we wrap our asset in a HTMLImageElement shim.

ExpoPixi.Sketch

A component used for drawing smooth signatures and sketches.

See the sketch example on how to save the images!

Notice: the edges and ends are not rounded as this is not supported in PIXI yet: Issue

Props

Property	Type	Default	Description
strokeColor	number	0x000000	Color of the lines
strokeWidth	number	10	Weight of the lines
strokeAlpha	number	1	Opacity of the lines
onChange	() => PIXI.Renderer	null	Invoked whenever a user is done drawing a line
onReady	() => WebGLRenderingContext	null	Invoked when the GL context is ready to be used

ExpoPixi.FilterImage

A Image component that uses PIXI.Filter

Props

Property	Type	Default	Description
resizeMode	string	null	Currently only supports cover, and contain
filters	Array<PIXI.Filter>	null	Array of filters to apply to the image
source	number, string, Expo.Asset	null	Source can be a static resource, image url (not {uri}), or an Expo.Asset

Example

Snack

import React from 'react';
import Expo from 'expo';
import { PIXI } from 'expo-pixi';

export default () => (
  <Expo.GLView
    style={{ flex: 1 }}
    onContextCreate={async context => {
      const app = new PIXI.Application({ context });
      const sprite = await PIXI.Sprite.fromExpoAsync(
        'http://i.imgur.com/uwrbErh.png',
      );
      app.stage.addChild(sprite);
    }}
  />
);