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From: greggw@iscnvx.uucp (William E. Gregg)
Newsgroups: comp.windows.x
Subject: question on using GC Functions for levels of overlap
Keywords: Graphical Context
Message-ID: <1991Apr18.013051.24770@iscnvx.uucp>
Date: 18 Apr 91 01:30:51 GMT
Sender: greggw@iscnvx.lmsc.lockheed.com
Organization: LMSC -  Information Services
Lines: 11

Can anyone give me some ideas on drawing overlapping objects on the screen
in such a way that the colors indicate the level of overlap (i.e. single,
double, triple, ...).  I have a slow brute force version, but I am interested
in a technique that would work during the drawing of each object.  I have
been looking at the GC Functions (GXxor, GXand, etc) and thinking that there
must be a clever way to accomplish this.  I have 8 bitplanes, so potentially
256 different levels of overlap could be kept track of.

Thanks in advance,
Bill Gregg
greggw@iscnvx.lmsc.lockheed.com