opacity

[SliMM]

Hello. I'm currently working on a set of functions for drawing semi-transparent bitmaps, rectangles and for using an alpha opacity channel with bitmaps

[xlarge]

Good... Intended for implemeting in rockbox?

[SliMM]

It is intended for implementing in the plugin api some time in the future. the first functions are attached. i'll work on bitmaps now. i think alpha channel can be another grayscale bitmap.
http://www.pastebin.ca/404924 <-- here is helloworld.c
http://www.pastebin.ca/404925 <-- here is the file with the functions, alphaopacity.c
http://stereo3d.adpeach.com/scrshot.jpg <-- here is a screenshot
Also, if anyone is interested in implementing Wu's line algorit, for anti-aliased lines, the pseudocode is here: http://en.wikipedia.org/wiki/Xiaolin_Wu's_line_algorithm

[SliMM]

I have finally finished a first set of semi-transparency functions.
Here is the link to the tracker task: http://www.rockbox.org/tracker/task/7022