Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!sco!mikep
From: mikep@sco.COM (Mike Patnode)
Newsgroups: comp.windows.x
Subject: XAllocColor() doesn't return closest color
Message-ID: <7924@scolex.sco.COM>
Date: 27 Sep 90 02:47:31 GMT
Sender: news@sco.COM
Reply-To: mikep (Mike Patnode)
Distribution: na
Organization: The Santa Cruz Operation, Inc.
Lines: 29


It seems that XAllocColor() will not try to approximate colors on
PseudoColor displays when none are available.  Given that you have a
full colormap, and the color you specifically want does not exist,
shouldn't XAllocColor() return the closest read-only color value
available?

In mit/server/dix/colormap.c, AllocColor() only does the following:

    case PseudoColor:
        if (FindColor(pmap, pmap->red, entries, &rgb, pPix, PSEUDOMAP,
                      client, AllComp) != Success)
            return (BadAlloc);
        break;

FindColor either finds the preexisting color, or allocates a new one.

Shouldn't FindBestPixel() be called when FindColor() fails?

Note that O'Reilly claims XAllocColor() should work this way, while the 
Red Book sort of side steps the issue.  Is the O'Reilly book just wrong?



-- 
Mike Patnode					The Santa Cruz Operation 
SCO Software Engineer				400 Encinal Street
{ucscc,uunet}!sco!mikep	 mikep@sco.COM  	P.O. Box 1900
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