Pixijs 2d

# PixiJS Examples and Patterns

Comprehensive real-world examples and patterns for building production-ready PixiJS applications.

## Table of Contents

1. [Basic Applications](#basic-applications)
2. [Interactive Elements](#interactive-elements)
3. [Particle Systems](#particle-systems)
4. [Filters and Effects](#filters-and-effects)
5. [Custom Shaders](#custom-shaders)
6. [Animation Patterns](#animation-patterns)
7. [Performance Optimization](#performance-optimization)
8. [Game Development](#game-development)
9. [UI Components](#ui-components)
10. [Framework Integration](#framework-integration)
11. [Mobile Optimization](#mobile-optimization)
12. [Advanced Techniques](#advanced-techniques)

---

## Basic Applications

### 1. Minimal PixiJS Application

The absolute minimum code to get started with PixiJS v8+:

```javascript
(async () => {
    const app = new PIXI.Application();

    await app.init({
        width: 800,
        height: 600,
        backgroundColor: 0x1099bb
    });

    document.body.appendChild(app.canvas);

    // Create a sprite
    const texture = await PIXI.Assets.load('bunny.png');
    const bunny = new PIXI.Sprite(texture);

    bunny.anchor.set(0.5);
    bunny.position.set(400, 300);

    app.stage.addChild(bunny);

    // Animation loop
    app.ticker.add((ticker) => {
        bunny.rotation += 0.05 * ticker.deltaTime;
    });
})();
```

### 2. Responsive Canvas Application

Canvas that automatically resizes to fill the window:

```javascript
(async () => {
    const app = new PIXI.Application();

    await app.init({
        width: window.innerWidth,
        height: window.innerHeight,
        backgroundColor: 0x1a1a2e,
        antialias: true,
        resolution: window.devicePixelRatio || 1,
        autoDensity: true
    });

    document.body.appendChild(app.canvas);

    // Handle window resize
    window.addEventListener('resize', () => {
        app.renderer.resize(window.innerWidth, window.innerHeight);

        // Reposition elements if needed
        updateLayout();
    });

    function updateLayout() {
        // Center content or adjust layout based on new dimensions
        const centerX = app.screen.width / 2;
        const centerY = app.screen.height / 2;

        // Update element positions...
    }
})();
```

### 3. Asset Loading with Progress

Load multiple assets with loading screen:

```javascript
(async () => {
    const app = new PIXI.Application();
    await app.init({ width: 800, height: 600 });
    document.body.appendChild(app.canvas);

    // Create loading text
    const loadingText = new PIXI.Text({
        text: 'Loading: 0%',
        style: { fontSize: 32, fill: 0xffffff }
    });
    loadingText.anchor.set(0.5);
    loadingText.position.set(400, 300);
    app.stage.addChild(loadingText);

    // Assets to load
    const assets = [
        { alias: 'bunny', src: 'bunny.png' },
        { alias: 'spritesheet', src: 'spritesheet.json' },
        { alias: 'background', src: 'background.jpg' }
    ];

    // Load assets with progress
    PIXI.Assets.load(assets, (progress) => {
        loadingText.text = `Loading: ${Math.round(progress * 100)}%`;
    }).then((textures) => {
        // Remove loading screen
        app.stage.removeChild(loadingText);

        // Start application with loaded assets
        startApp(textures);
    });

    function startApp(textures) {
        const bunny = new PIXI.Sprite(textures.bunny);
        bunny.position.set(400, 300);
        app.stage.addChild(bunny);
    }
})();
```

### 4. Multi-Scene Application

Manage multiple scenes/screens:

```javascript
class SceneManager {
    constructor(app) {
        this.app = app;
        this.scenes = new Map();
        this.currentScene = null;
    }

    addScene(name, scene) {
        this.scenes.set(name, scene);
        scene.visible = false;
        this.app.stage.addChild(scene);
    }

    switchTo(name) {
        if (this.currentScene) {
            this.currentScene.visible = false;