Hungry Bubble

An arcade-style game, inspired by 'Feeding Frenzy', made for Tweet Tweet Jam 9.

How to play:
Use the arrow keys or controller d-pad to move your bubble. Touch smaller bubbles to grow, but avoid the edges of the screen and bubbles that are larger than you. Your current radius is shown in the top-left corner. The game will inevitably end when your radius exceeds the screen - if you can last that long!

I'm pretty happy with how I was able to condense this down. I used some very short expressions to gather input, without any branching, and found lots of places where I could condense array references to a single character variable. I was a bit disappointed that I had to run the same length FOR loop to initialise the bubbles as I did to draw them and check collisions (surely, loops of the same number of iterations are begging to be combined and optimised, right?) but it turns out that combining them would require branching, and once that was done, it didn't actually condense the code further. It may be possible to construct a shorter game loop so that you can 'fall through' to the ending state, instead of having to use a GOTO. It's also definitely possible to squeeze in a few more bytes by combining some more of the lines. But I don't think I'd gain much from that; I'm happy to leave this in its current playable form, sitting at exactly 500 characters.