From:	"Graham Reeds" <grahamr AT dtn DOT ntl DOT com>
Newsgroups:	comp.os.msdos.djgpp
References:	<8s4r4u$lc7$1 AT news DOT kabelfoon DOT nl>
Subject:	Re: drop shadow
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Date:	Thu, 12 Oct 2000 19:23:32 +0100
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To:	djgpp AT delorie DOT com
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You could simulate a shadow by redrawing the image slightly offset to the
original image - i.e. two or three pixels to the left or right - as a on/off
mask to darken the underlying image (i.e. the speedo itself).  How you would
do it specifically in Allegro, I don't know, but it might be as simple as
reading in the pixel value and subtracting a fixed value off it (say 32 so
we could use a shift) and clamp it so we don't affect any other components
of the colour.

Hope that helps.
--

Stay Lucky, Graham "Mournblade" Reeds.
ICQ No.:  30514803
http://homepage.dtn.ntl.com/grahamr

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