Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!rphroy!caen!uwm.edu!bionet!agate!usenet.ins.cwru.edu!ysub!psuvm!cxt105
From: CXT105@psuvm.psu.edu (Christopher Tate)
Newsgroups: comp.sys.mac.programmer
Subject: Palette Manager question
Message-ID: <91106.132819CXT105@psuvm.psu.edu>
Date: 16 Apr 91 17:28:19 GMT
Organization: Penn State University
Lines: 30

I've got a bizarre little application with a bizarre little problem.
Basically what I'm doing is twiddling bits in an off-screen CGrafPort
directly and then blasting the result into a window with CopyBits.  So
far, so good; the CopyBits works, etc.  However, I've got a problem with
the Palette Manager.

I want to use (say) n shades of grey in my window; unfortunately, for rather
exotic reasons it is essential that these shades of grey be represented in
the offscreen CGrafPort by the pixel values 0 through n-1.  I can't seem to
get the Palette Manger to do what I want it to.  What I *want* is to set up
a palette with my desired colors in it, and have those colors appear when I
CopyBits the image into the window.  What's happening is that I'm getting
the first n colors in the default system palette, not my greyscales.

If I use the Color Manager to SetEntries() on the first n colors, then I get
exactly what I want; unfortunately, I'm not sure how to go about saving and
restoring the original color map if I do that -- it gets *very* ugly on the
rest of the screen!

Do I have to (somehow) associate the palette I want to use with the CGrafPort
as well as with the Window?  Do I have to muck about with CLUT's?  How should
I go about resetting the original palette/CLUT/whatever when my application
quits?  Etc....

-------
Christopher Tate                   |
                                   | "An operating system, like a government,
cxt105@psuvm.psu.edu               |  performs no useful function by itself."
{...}!psuvax1!psuvm.bitnet!cxt105  |
cxt105@psuvm.bitnet                |