Expert skill for building web-based game engines and games using HTML5, Canvas, WebGL, and JavaScript. Use when asked to create games, build game engines, implement game physics, handle collision detection, set up game loops, manage sprites, add game controls, or work with 2D/3D rendering. Covers te

Game Engine Skill Build web based games and game engines using HTML5 Canvas, WebGL, and JavaScript. This skill includes starter templates, reference documentation, and step by step workflows for 2D and 3D game development with frameworks such as Phaser, Three.js, Babylon.js, and A Frame. When to Use This Skill Building a game engine or game from scratch using web technologies Implementing game loops, physics, collision detection, or rendering Working with HTML5 Canvas, WebGL, or SVG for game graphics Adding game controls (keyboard, mouse, touch, gamepad) Creating 2D platformers, breakout style games, maze games, or 3D experiences Working with tilemaps, sprites, or animations Adding audio to web games Implementing multiplayer features with WebRTC or WebSockets Optimizing game performance Publishing and distributing web games Prerequisites Basic knowledge of HTML, CSS, and JavaScript A modern web browser with Canvas/WebGL support A text editor or IDE Optional: Node.js for build tooling and local development servers Core Concepts The following concepts form the foundation of every web based game engine. Game Loop Every game engine revolves around the game loop a continuous cycle of: 1. Process Input Read keyboard, mouse, touch, or gamepad input 2. Update State Update game object positions, physics, AI, and logic 3. Render Draw the current game state to the screen Use requestAnimationFrame for smooth, browser optimized rendering. Rendering Canvas 2D Best for 2D games, sprite based rendering, and tilemaps WebGL Hardware accelerated 3D and advanced 2D rendering SVG Vector based graphics, good for UI elements CSS Useful for DOM based game elements and transitions Physics and Collision Detection 2D Collision Detection AABB, circle, and SAT based collision 3D Collision Detection Bounding box, bounding sphere, and raycasting Velocity and Acceleration Basic Newtonian physics for movement Gravity Constant downward acceleration for platformers Controls Keyboard Arrow keys, WASD, and custom key bindings Mouse Click, move, and pointer lock for FPS style controls Touch Mobile touch events and virtual joysticks Gamepad Gamepad API for controller support Audio Web Audio API Programmatic sound generation and spatial audio HTML5 Audio Simple audio playback for music and sound effects Step by Step Workflows Creating a Basic 2D Game 1. Set up an HTML file with a <canvas element 2. Get the 2D rendering context 3. Implement the game loop using requestAnimationFrame 4. Create game objects with position, velocity, and size properties 5. Handle keyboard/mouse input for player control 6. Implement collision detection between game objects 7. Add scoring, lives, and win/lose conditions 8. Add sound effects and music Building a 3D Game 1. Choose a framework (Three.js, Babylon.js, A Frame, or PlayCanvas) 2. Set up the scene, camera, and renderer 3. Load or create 3D models and textures 4. Implement lighting and shaders 5. Add physics and collision detection 6. Implement player controls and camera movement 7. Add audio and visual effects Publishing a Game 1. Optimize assets (compress images, minify code) 2. Test across browsers and devices 3. Choose distribution platform (web, app stores, game portals) 4. Implement monetization if needed 5. Promote through game communities and social media Game Templates Starter templates are available in the assets/ folder. Each template provides a complete, working example that can be used as a starting point for a new project. Template Description paddle game template.md 2D Breakout style game with pure JavaScript 2d maze game.md Maze game with device orientation controls 2d platform game.md Platformer game using Phaser framework gameBase template repo.md Game base template repository structure simple 2d engine.md Simple 2D platformer engine with collisions Reference Documentation Detailed reference material is available in the references/ folder. Consult these files for in depth coverage of specific topics. Reference Topics Covered basics.md Game development introduction and anatomy web apis.md Canvas, WebGL, Web Audio, Gamepad, and other web APIs techniques.md Collision detection, tilemaps, async scripts, audio 3d web games.md 3D theory, frameworks, shaders, WebXR game control mechanisms.md Touch, keyboard, mouse, and gamepad controls game publishing.md Distribution, promotion, and monetization algorithms.md Raycasting, collision, physics, vector math terminology.md Game development glossary game engine core principles.md Core design principles for game engines Troubleshooting Issue Solution Canvas is blank Check that you are calling drawing methods after getting the context and inside the game loop Game runs at different speeds Use delta time in update calculations instead of fixed values Collision detection is inconsistent Use continuous collision detection or reduce time steps for fast moving objects Audio does not play Browsers require user interaction before playing audio; trigger playback from a click handler Performance is poor Profile with browser dev tools, reduce draw calls, use object pooling, and optimize asset sizes Touch controls are unresponsive Prevent default touch behavior and handle touch events separately from mouse events WebGL context lost Handle the webglcontextlost event and restore state on webglcontextrestored

game-engine