Path: utzoo!mnetor!uunet!husc6!bbn!gatech!dcatla!dudkl
From: dudkl@dcatla.UUCP (Danny K. Llewallyn)
Newsgroups: comp.lang.postscript
Subject: Seethru fills
Message-ID: <4097@dcatla.UUCP>
Date: 29 Apr 88 12:22:57 GMT
Organization: DCA, Inc., Alpharetta, GA
Lines: 40
Keywords: Show what's underneath

I am looking for a good way to fill a path with a specified grayscale
level without covering-up what has already been placed on the page.
Ideally what I want is either a true / false parameter to the image
operator or a bits/sample parameter to the imagemask operator.  Since
PostScript does not currently have either,  I have been toying around
with a method using what we alreay have.  The program below prints a
fairly good .5 grayscale,  but I am soliciting the net for better
methods of doing any grayscale see-thru fill.


Thanks in Advance for Responses,


Danny.


/str1 50 string def
/str2 50 string def

0 1 49 {str1 exch 16#55 put} for
0 1 49 {str2 exch 16#AA put} for
/Helvetica-Bold findfont 32 scalefont setfont
200 200 translate
-30 100 moveto (Background Stuff) show
400 400 scale
/flag false def
400 400 true [400 0 0 400 0 0]
{
  flag
  {/flag false def str1}
  {/flag true def str2}
  ifelse
}
imagemask
showpage

-- 
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-{   What good is freedom?  God laughs at people like us.   - Talking Heads  {-
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