Monday, September 7, 2009

Brick Break - a Javascript Breakout clone

This weekend I wrote a Javascript clone of the old Atari "Breakout" game. Thanks to the "Canvas" tag it was very easy to write, but I did run into a few problems:

Javascript math is always floating point, so I had to use the "Math.floor" function to convert the results of a division to an integer. This was in the brick collision detection logic, where I am converting the ball's (x,y) coordinates to the bricks that the ball might be hitting.

I was evaluating document.getElementById too early in the document lifecycle, before the corresponding elements existed. This took me a long time to diagnose -- I ended up just moving the getElementById calls to their run-time use, rather than trying to cache the results.

Jack's Brick Break Breakout clone

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