The performance is quite bad here. Thanks to antialiasing and alpha (I guess). For the most part that stuff could be done with cheating. Hm... actually... you could do everything with generated bitmasked and opaque images and it would still look pretty much the same - just with more fps.
That's strange... there isn't a single machine i tried the game and had perfomance issues. In fact, i was able to put a lot of squares in there (and they're just... squares, not anything fancy) without framerate drop. You're the first to tell me that there is such an issue. Can you please tell me your system specs?
Note that while the antialiasing in the main square and the "bullets" could be done with generated bitmasked images, when the bullets were intersecting each other or other squares, the "antialiasing" would show itself and the result would be ugly. The same applies for the main square itself intersecting other squares. Also there is no method i can think of that will mimic alpha blending. The game's graphics are simple primitives. Removing antialiasing and alpha blending will make it way too ugly.
One thing that i wanted to avoid in this game was pixellation. Most (almost every) games written in Java as applets are pixellated (in fact the first thing i think when i see a pixellated webgame is that is written in Java, for that reason alone). Flash games use antialiasing for ages and since Java provides Java2D which supports antialiasing, i'll stick with that.
Gameplay wise it's bad that you cannot aim, which makes it feel a bit more random then necessary.
I wanted to design a game that can be controlled as easylly as possible. Adding both aim and avoiding the enemy squares would complicate controls a lot. I prefer to keep it simple.
You're using the mouse position directly, which is a common mistake to make (often seen in flash, too). With a modified html or with the appletviewer you can use a bigger area, which allows you to leave the playing field. If you take a look at the highscore list you can see me at #1 (clampglitch). To fix the problem clamp the mouse coords and use those clamped values.
That's really something i didn't thought!
I'll fix it, thanks for telling me about :-).
It's sorta easy to overlook the items. Additional visual clues could sort that out for example.
That's something other people mentioned too, so i think i'll think a bit on how to do that without changing the gameplay.
In any case, thank you for your feedback :-)