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Hello everyone, Recently i finished my first medium-sized HTML5 game - Medieval Defense Z. I came from flash background and developing for HTML5 presented with some new challenges. So i would like to share what worked and what didn't. This is more like review/tutorial type of thing, so hopefully someone will find something useful. • Goals: • 60fps. • Smooth gameplay and animations. • Quality comparable to flash games. • Tools: • Language: Haxe. Strictly typed programming language, similar to ActionScript 3.0. Compiles to all major languages, including javascript. • Editing: HaxeDevelop IDE. Freeware, great code completion and very fast compared to everything i tried. • Debugging: Chrome. Has console, debugger and profiler. • Rendering library: Pixi.js. Uses display list concept like flash. Works well. • Sound library: Howler. Good enough, the id system is a bit weird though. • Bitmap font exporter: http://kvazars.com/littera/. Free and web-based. • Sprite Sheet Packer: https://spritesheetpacker.codeplex.com/. Freeware and very simple. • Graphics: • Scaling will look ugly if you use many small png files for textures. • If you want nice scaling, fast load times and fast rendering - pack everything to 2048x2048 spritesheets (include bitmap fonts too). • Resolution of assets: 1024x768, background can extend to 1382x768, so it covers most aspect ratios in horizontal orientation. • To get proper native resolution in mobile browsers i scaled up renderer and scaled down canvas by window.devicePixelRatio. • Sounds: • Library: Howler. • Sound formats: ogg for Chrome and Firefox, m4a for Safari and Internet Explorer (note: mp3 has licensing issues with play count). • ffmpeg: because of licensing issues and whatnot can't convert to m4a, unless you recompile ffmpeg with m4a, which is a pain to setup. • I used MediaHuman Audio Converter (freeware) to convert from wav to ogg and m4a (64 bit). • iOS Safari: keep in mind that before any sound could be played, user must first tap on the screen. • Mouse Events: • Used pixi.js API to open links. • iOS Safari: window.open under "touchstart" event won't open links in new tabs, use "tap" event instead. • sprite.on("mousedown", callback) for desktop. • sprite.on("tap", callback) for mobile. • Performance: • Reuse frequently used sprites. • Avoid creating too many objects every frame. • I would recommend looking up data-oriented programming to get more juice out of Javascript. • Record timeline with Chrome profiler to find performance bottlenecks. • Masks are slow. Use trim if you only need a simple cut. • Very large functions may cause lag spikes. My best guess is that browser is trying to optimize the function. Splitting big function into several smaller ones solved my problem. • Game Debugging: • Simple CSS + DOM side menu. • Basic field view/edit. • Simple buttons with callbacks. • How to debug html5 game on android (mobile) with desktop chrome (PC): 1. Upload game to your website. 2. Go to (desktop) chrome: chrome://inspect 3. Connect Android device with USB and run your game on android chrome (your android device must be enabled for development). 4. Open Command Prompt and enter: adb devices (must have Android Debug Bridge installed). 5. To quit debugging enter: adb kill-server • Conclusions: • Programming in Haxe instead of pure Javascript probably saved hours and hours of debugging. • Would have liked more automated solution for spritesheet and sound stuff. • Poor performance bites sooner or later, so be prepared to do extensive profiling. • Stable 60fps is very hard to achieve, even if you keep your code below 1-2ms per frame. • Overall i am happy with the results, however it took longer than expected to make this game. Any feedback is appreciated. Game Link: http://html5games.vooxe.com/a90bd3f1fba643828ccfb0109b41a252/index.html Trailer: