05 May 2010

Flixel Feedback

I’ve recently completed a game (no link as it’s not yet clear if I can mention my involvement) built using Flixel, a framework primarily intended for building retro-styled pixellated Flash games via the free Flex compiler. Here’s a quick summary of my impressions.

The Good

• Performance is great.
• The way sprites are grouped (and groups can be grouped, etc.) is flexible and intuitive.
• Certain types of game are very, very easy to get up and running.
• If you run into a problem, the solution is often to be found in the forum (always a good sign).
• There are useful third-party tools for building things like tilemaps (e.g. Flan).
• The documentation and source code are clear and understandable.

The Bad

• There doesn’t seem to be any way of dynamically controlling depth sorting (needed for anything with a forced perspective).
• It’s not always obvious how you’re supposed to use similar properties, e.g. dead vs. exists.
• You can’t show the pointer while there’s scrolling without it jittering around (due to a rounding problem in the positioning maths; I used an ugly hack to avoid it).
• I had to modify the core Flixel code in two places, to disable the pop-up console (it’s easy for players to accidentally trigger it and become confused) and be able to toggle the useDefaultHotKeys setting during the game (so that P wouldn’t pause the game if typed for the high score table).
• Some confusion arises from most tutorials referring to features that have since changed.
• The Flixel site currently recommends downloading Flex 3 SDK v3.4, but using this triggers a compilation error with the latest Flixel until a line of code is edited.

The Ugly

• The biggest problem wasn’t with Flixel, it was with simply coaxing Flex into compiling anything. I had to change file permissions, faff about with path settings, fix line endings, and probably more during hours of head-scratching; none of the ‘quick start’ guides worked for me.

Although I’ve listed several grumbles, overall it’s a great piece of work that’s very generously given away for free. It’s ideal for anyone with intermediate-level ActionScript and OO skills who wants to put together Flash games, but be prepared for a bit of command-line wrangling and the occasional puzzling or glitchy feature.