Game Development With HTML5
Download as PPT, PDF59 likes12,231 views
The document discusses the development of games using HTML5, JavaScript, and related technologies, highlighting the advantages of the HTML5 canvas for graphics and audio. It includes various code examples, demos, and resources for creating games, while mentioning the limitations and future prospects of web technologies like WebGL and WebSocket. The content emphasizes the ease of debugging and open-source tools available for developers.
![<games /> Gil Megidish [email_address]](https://image.slidesharecdn.com/games-100518125023-phpapp01/85/Game-Development-With-HTML5-1-320.jpg)
![Accessing Pixels var block = ctx.getImageData(0, 0, canvas.width/2, canvas.height); for (var y=0; y<block.height; y++) { for (var x=0; x<block.width; x++) { block.data[(y*block.width+x)*4+0] ^= 0xff; block.data[(y*block.width+x)*4+1] ^= 0xff; block.data[(y*block.width+x)*4+2] ^= 0xff; } } ctx.putImageData(block, 0, 0);](https://image.slidesharecdn.com/games-100518125023-phpapp01/85/Game-Development-With-HTML5-29-320.jpg)
![Q&A Yes! You can use <canvas> in Internet Explorer 6? <!--[if IE]> <script type="text/javascript“ src="/js/excanvas.js"> </script> <![endif]--> PS. Remember to upgrade your mother’s IE!](https://image.slidesharecdn.com/games-100518125023-phpapp01/85/Game-Development-With-HTML5-41-320.jpg)
Game Development With HTML5
- 1. <games /> Gil Megidish [email_address]
- 2. And I love writing / rewriting / reverse engineering games
- 4. What The Heck is HTML5 Canvas Video Audio Web Sockets Web Storage Web Worker Web Database Selectors Validation File API Semantic Elements
- 5. Man will make it to Mars before HTML5 is on my Firefox! W3C’s ETA: Year 2022
- 6. Games + Javascript? = wtf
- 7. Why Bother With Javascript? Fun to develop Hacker’s spielplatz! Fast deployment Serve static files Easy to debug alert(), firebug.. Still better than the alternative! Open source and free tools Notepad, vi, emacs B.Y.O. framework jQuery? spielplatz
- 8. But Why REALLY? Has been around for ages Won’t go away any time soon Wide support: Web browsers Mobile devices Facebook applications On a rocket near you
- 9. Anatomy of a Game LOGIC GRAPHICS INPUT SOUND MUSIC MULTIPLAYER GAME ASSETS
- 10. Anatomy of a Game LOGIC GRAPHICS INPUT SOUND MUSIC MULTIPLAYER GAME ASSETS javascript code <canvas> onkeydown, onmousedown <audio> <audio> ajax, WebSocket Images, Audio, Video and Binary supported by browsers
- 11. Graphics
- 12. Framebuffer (raw) 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,x 1,0 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,x y,0 y,1 y,2 y,3 y,4 y,5 y,6 y,7 y,x x y … … … . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
- 14. Tile + Sprite Memory
- 16. Scene Graph Placeholder For Future Presentation
- 18. Canvas is King
- 19. DEMO TIME!
- 20. Three Demos To Rule Them All Framebuffer demo http://www.megidish.net/apple2js/ Sprites demo http://www.megidish.net/alphageeks6/luigi/ Vector graphics demo http://www.megidish.net/awjs/
- 21. Catch me a canvas <canvas id=“graphics” width=“640” height=“480”> Guru Meditation: No canvas supported! </canvas> var canvas = document.getElementById(“graphics”); var context = canvas.getContext(“2d”);
- 23. Drawing Primitives ctx.fillStyle = “#c80000"; ctx.fillRect (10, 10, 55, 50); ctx.fillStyle = "rgba(0, 0, 200, 0.5)"; ctx.fillRect (30, 30, 55, 50); Other drawing methods: arc, bezierCurve, lineTo, quadraticCurve, rect, stroke, fillText, strokeText, beginPath/closePath and fill
- 24. (but who needs that ?)
- 25. Drawing Images var sprite = new Image(); sprite.src = “luigi.png”; var x = 0, y = 0; ctx.drawImage(sprite, x, y);
- 26. Drawing Images 2 var spritemap = new Image(); spritemap.src = “sprite-map.png”; ctx.drawImage( spritemap, sx, sy, sw, sh, dx, dy, dw, dh ); Sprite maps save loading time by fewer requests and better compression. drawImage() also provides scaling and cropping.
- 27. Going Crazy With Images // context state checkpoint ctx.save(); ctx.translate(0, 80); ctx.rotate(-45 * Math.PI / 180.0); ctx.scale(3.0, 1.0); ctx.drawImage(luigi, 0, 0); // revert all context changes ctx.restore();
- 28. Accessing Pixels var block = ctx.getImageData(sx, sy, sw, sh); block = { width: width in pixels, height: height in pixels, data: array of 4*width*height bytes }; Alternatively: ctx.createImageData(w, h);
- 29. Accessing Pixels var block = ctx.getImageData(0, 0, canvas.width/2, canvas.height); for (var y=0; y<block.height; y++) { for (var x=0; x<block.width; x++) { block.data[(y*block.width+x)*4+0] ^= 0xff; block.data[(y*block.width+x)*4+1] ^= 0xff; block.data[(y*block.width+x)*4+2] ^= 0xff; } } ctx.putImageData(block, 0, 0);
- 30. Why Access Pixels ? Complicated things impossible without putImageData() Read image pixels getImageData combined with primitive drawing = save image to disk! These examples are available to http://www.chromeexperiments.com/
- 31. The Jazz Singer
- 32. Let There Be Sound! <audio id=“sfx001” src=“/mp3/boom.mp3”></audio> $(“sfx001”).play();
- 33. Let There Be Sound! <audio id=“sfx001” src=“/mp3/boom.mp3”></audio> $(“sfx001”).play(); Other methods: $(“sfx001”).pause(); Other attributes: $(“sfx001”).currentTime = 35.0; $(“sfx001”).volume = 0.5; $(“sfx001”).duration (read only)
- 34. Putting It All Together
- 35. Typical Game Loop function gameTick() { processKeyboard(); moveEnemies(); drawGraphics(); updateAudio(); } var fps = 60; setInterval(gameTick, 1000 / fps);
- 36. The Future is Upon Us!
- 37. Quake2 HTML5
- 38. What’s Coming Up Next WebGL OpenGL interface for Javascript As of May, 2010: good luck finding a stable browser! WebSocket UDP and nonblocking transport layer Not there yet! (KAAZING?) WebStorage Save games?
- 39. Code Like It’s 2020! ftw! ‘ s Blackberry coming June 1 st !
- 40. Q&A
- 41. Q&A Yes! You can use <canvas> in Internet Explorer 6? <!--[if IE]> <script type="text/javascript“ src="/js/excanvas.js"> </script> <![endif]--> PS. Remember to upgrade your mother’s IE!
- 42. Links! Chrome Experiments: Not Your Momma’s JS http://www.chromeexperiments.com Appcelerator’s Titanium www.appcelerator.com Box 2D: real time physics for JS games http://box2d-js.sourceforge.net/index2.html Mozilla’s Canvas tutorial https:// developer.mozilla.org/en/Canvas_tutorial
- 44. GO MAKE GAMES! http://www.megidish.net