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Article #12581vfont bitmap alignment (Re: versatec font editor)
From: Don't tell me the rerun season h...
Date: Sat, 06 May 1989 16:02
Date: Sat, 06 May 1989 16:02
34 lines
1991 bytes
1991 bytes
>X-Sun-Spots-Digest: Volume 7, Issue 245, message 16 of 15
>
> ...
>
>... By the way: there is a small but important
>difference between Berkeley's standard "vfont" format and the one that Sun
>uses: the bitmaps for standard vfonts are byte aligned, but the bitmaps
>for Sun vfonts are *word* aligned! --wnl
This is incorrect, the bitmaps in Sun vfont files are byte aligned
(padded). There's an old ditroff previewer floating around which also
thinks vfonts are short padded; maybe that's what caused the confusion.
vfont(5) is pretty clear:
The bit map contains up+down rows of data for the character, each
of which has left+right columns (bits). Each row is rounded up to
a number of bytes.
If that's not convincing, let's look at a typical screen font...
% vfontinfo screen.r.7 ab
Font screen.r.7, raster size 760, max width 6, max height 6, xtend 2
ASCII offset size left right up down width
screen.r.7 141 a 520 8 0 6 6 2 6
screen.r.7 142 b 528 8 0 6 6 2 6
The bitmap for 'a' occupies 8 bytes, therefore each scan line is 1 byte.
Q.E.D.
--
David DiGiacomo, Sun Microsystems, Mt. View, CA sun!david david@sun.com
[[ Okay. At one point they WERE word aligned, around about version 2. I
just assumed that that was still the case. --wnl ]]
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request From: david@sun.com (Don't tell me the rerun season has started already!?!?!?!) Newsgroups: comp.sys.sun Subject: vfont bitmap alignment (Re: versatec font editor) Keywords: Software Message-ID: <8904251720.AA16670@david.sun.com> Date: 6 May 89 16:02:42 GMT References: <5019@cs.Buffalo.EDU> Sender: usenet@rice.edu Organization: Sun-Spots Lines: 34 Approved: Sun-Spots@rice.edu Original-Date: Tue, 25 Apr 89 10:20:38 PDT X-Sun-Spots-Digest: Volume 7, Issue 272, message 18 of 19