Combine pictures transparently at ANY percent!

This killer code demonstrates the fastest and most efficient way to combine pictures transparently. Designed to be used in a paint program or game, this picture will combine 2 pictures at any percent transparency. I haven't seen code of this nature anywhere else on the site, so be sure to check this out. This code could also be used to fade pictures into eachother (like they do in MYST with transitions mode on), if you're interested. Includes picture loading and saving code as well.