You can influence bitmaps however you like.

1. Lock the bitmap with http://www.conitec.net/beta/abmap_lock.htm
2. Read pixels from the bmap with http://www.conitec.net/beta/apixel_for_bmap.htm
3. Write pixels to the bitmap with http://www.conitec.net/beta/apixel_for_vec.htm
4. Unlock the bitmap with http://www.conitec.net/beta/abmap_unlock.htm

Always learn from history, to be sure you make the same mistakes again...