I was thinking of doing a algoritem that finds starting and ending points, and then drops the whole rectangle from X1 to X2, Y1 to Y2... but i didnt figure it out so far and it wouldnt be too exact, because it could drop some pixels, that would be in that rectangle but not in the floating dirt.

It would probobaly be more exact if i would do it with columns like will said, but i'd stil need to have a algoritem that would tell if that column is a part of the floating dirt or not.

About the slowdown... its about 40-60fps on my computer without the floating dirt detection procedure, and it still works smooth on 20-25fps at my friends computer, so i hope i can make it fast enough. Too bad i don't know any ASM yet... anyone knows any good tutorials. I should check some ASM stuff out anyway, cause we'll gonna start learning it in school next year.

Anyways... I'm making a game named Djuk Njuk, and it is suposed to look like something like duke nuke 1 and 2, and play like worms.