steele@unc.cs.unc.edu (Oliver Steele) (12/06/87)
Ted Johnson (tedj@hpcilzb.HP.COM) (Puzzled in Peoria) asks how
"dissolving" text/pictures are done.
CopyMask, which works like CopyBits except that it only copies source to
destination in those places where the bits in a "mask" bitmap are set, is
used for dissolves. If you draw a picture to a bitmap and copy the bitmap
to the screen with a mask of ltgray you'll have a 1/4 dissolve from the
what was on the screen originally to the new picture, and then you can do
the same with a mask of gray and finally of black and you'll have a fairly
smooth dissolve. To make it look really nice, you'll want to make your
own patterns to use in the mask, and you can fill the mask with successive
moving bands or spirals or various other images to do different types of
dissolves.
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Oliver Steele ...!{decvax,ihnp4}!mcnc!unc!steele
steele%unc@mcnc.org
"No snappy quote" -- Richard Siegel