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From: jwz@lucid.com (Jamie Zawinski)
Newsgroups: comp.lang.postscript
Subject: Re: Help!
Message-ID: <JWZ.90Sep13112918@kolyma.lucid.com>
Date: 13 Sep 90 18:29:18 GMT
References: <265@pb2esac.UUCP>
Sender: jwz@lucid.com
Organization: Lucid, Inc., Menlo Park, CA
Lines: 24
In-reply-to: rgrodrig@pb2esac.UUCP's message of 13 Sep 90 03:00:28 GMT

In article <265@pb2esac.UUCP> rgrodrig@pb2esac.UUCP (Robert Rodriguez) writes:
> The object:
>	To convert an X11 bitmap image (solid black logo) into
>	postscript, then use "setgray" (I think) to make the image lighter,
>	and put some text over it.
> The method:
>	I've used the PBMPLUS package to convert the bitmap
>	into postscript without a problem.  Then I thought I'd just add
>	a ".5 setgray".

setgray only affects what the "lineto", "fill" etc commands do.  It doesn't
affect bitmaps.  Also, what you really want (I think) is to take a bit of
PostScript code and make it (say) 50% lighter.  If the code had setgray's in
it, they would override the setgray you did.  Try this:

	/fade-factor 0.25 def
	gsave
	  { 1 exch sub fade-factor mul 1 exch sub } settransfer
	  < put the code you want to lighten here >
	grestore

This will make the image be 25% of full intensity.

		-- Jamie