There's one in the code archives. In fact there's quite a few. :)
Colorfade (to/from) black algorithm
BlitzPlus Forums/BlitzPlus Programming/Colorfade (to/from) black algorithmThe forum is locked. These are the original blitzbasic.com forums, kept so they can still be read. No new topics, replies or edits can be made here. To join in, head over to the Blitz3D+ forums.