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From: mishkin@apollo.UUCP.UUCP
Newsgroups: mod.computers.apollo
Subject: Re: text background color and gpr_$text
Message-ID: <8606030402.AA27159@uw-beaver.arpa>
Date: Mon, 2-Jun-86 14:03:24 EDT
Article-I.D.: uw-beave.8606030402.AA27159
Posted: Mon Jun  2 14:03:24 1986
Date-Received: Tue, 3-Jun-86 22:09:30 EDT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 41
Approved: apollo@yale-comix.arpa


    I'm using gpr_$text to draw characters on the screen. 
    Suppose I have the text background color set to white, and
    the text drawing color set to black, and imagine drawing text
    onto a solid black screen.  Rather than getting a contiguous
    white box with the characters in it, I get a bunch of
    discontiguous white boxes with black gaps between them --
    which is not what I want.
    
    Question:  is this a bug or a "feature"?  

Forwarded from someone who should know:

=============================================================================

I guess its a feature.  gpr_$text only ever draws the bits that are actually
present in the font.  There are lots of ways around this:

1) if you want black-on-white everywhere, and you are using borrow mode,
   call gpr_$set_color_map with pixel value zero set to one, and so on.  Then
   do your text normally.

2) if you just want text that is inverted in some places then either:

   a) call gpr_$rectangle to clear the text field to the desired background
      first.  This may seem annoying, but its the way bitmap graphics with
      general fonts works everywhere as far as I know.
   b) if you are lazy and don't mind using one of the standard fixed width
      fonts, we ship several "inverted fonts".  They are the ones with .iv
      in their names.  They not only have all the bits inverted in the font,
      but have no inter-character spacing, and have an extra pixel of background
      surrounding each character.  CRP and DSEE, for example, use these fonts
      to display their banners.

=============================================================================

                -- Nat Mishkin
                   Apollo Computer Inc.
                   apollo!mishkin

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