This isn’t a new article, but it touches on a topic I’ve heard a lot about recently. That is, pixel ‘blitting‘. Blitting is an old school process used in sprite-based games of essentially erasing a spot in a bitmap image based on a sprite’s alpha and using a bitwise operator to draw the sprite into that bitmap image. Most graphics systems do this transparently to the user in some fashion (pardon the pun). 8-Bit Rocket has a good introduction to these concepts with regards to Flash, but read on for the important part of this post.
Read the article on Photon Storm
The article shows that Flash Player is already fairly optimized for graphical composition operations when compared to blitting. Both showed similar framerates. However, the cacheAsBitmap operation caused an exponential increase in memory consumption when the number of sprites on stage increased. Ironically, the comparison was run by the creator of the Pixel Blitz library who, I’m sure, had a difficult time presenting the results.
There are some good details in the article so if you’re interested, read the whole thing before you decide if you agree.
Have you done any work with bit blitting or sprite sheet animation? Have you found it to be beneficial? Tell us your thoguhts.
