“What would be something neat to do in JavaScript?” – I kept asking myself that on Saturday. My fiance was away for the weekend and I was just kind of hanging out at home with the dog. Eventually I ended up thinking about possibly trying to do a side scroller game, like Mario Bros or Commander Keen, but since I had never written one before, I wasn’t sure. Finally, I came to the conclusion that it might be wiser to go for something a little easier first, and decided it might be cool to port my old “Intergalactic Odyssey” space ship game to JavaScript.

My goals here were to just see how feasible it would be to create an action game with moving sprites. I didn’t get very far, but I was able to create a space ship that could fly around and shoot lasers. I was able to get the graphics by decompiling my old SWF Flash file (I’ve long lost the source to the game). Also, the space ship artwork was done by fitz. I originally found the space ship via Google Images, though I did ask before I used it.

So far the main issue I’ve run into is that IE and FireFox aren’t reliable for smooth game play. The demo works best in Google’s Chrome and Opera’s Opera web browser. Though at this point I haven’t added any collision detection in, or any bad guys in, so there’s still a ways to go before I know if I’ll have a playable game.

One thing I didn’t realize when I started was that I could rotate images. I googled for a little bit and didn’t come up with anything, so I wound up creating images for each of the different rotations of the space ship. Though now that I’ve read up on it a little more, image rotation can apparently be done with the Canvas object in FF, Opera and Chrome, and with filters in IE. I suppose I’ll find out later which method is faster.

Lastly, the key capturing events are a little frustrating, since JavaScript doesn’t appear to remember when someone is holding the Up-arrow down if another key is pressed while its down. I’m still trying to figure out if there’s a way to get around this.

If you have any tips/suggestions, feel free to let me know.