mac drawing programs

Conrad Halling chhall at bb1t.monsanto.com
Tue Mar 22 14:09:31 EST 1994


In article <2mn326$knb at mserv1.dl.ac.uk>, "Michael D. Baron"
<michael.baron at afrc.ac.uk> wrote:

> >In article <Lab_Mac_Hanson-180394091936 at 128.84.203.227>,
> >Lab_Mac_Hanson at QMrelay.mail.cornell.edu (Hanson Lab) wrote:
> 
> > We have this problem... Does anyone else have a solution?  If one downloads
> > a PUBLISH file from GCG (VAX), and then tries to import that file into a
> > Macintosh drawing program like MacDraw Pro, the text begings to act
> > strange.  If one tries to  box a segment of sequence, or bold a segment of
> > sequence, or underline a segment of sequence within that file, although on
> > the screen evrything looks great, when the resultant file is printed, the
> > altered text has *moved* relative to the rest of the text.
> 
> To which J.Parkill at bham.ac.uk replied:
> 
> >There is a cure for this problem, but only for those using MacDraw Pro (I'm
> >using version 1.5v1)
> 
> >Under the "Layout" menu, chose "Preferences..."
> >Within the preferences dialog, choose "Printing".
> >At the bottom is a pair of Radio Buttons for "Standard character placement"
> >or "Precise character placement"
> 
> >Clicking "Precise character placement" should print the character exactly
> >the way that they appear on the screen.

It is often also necessary to click on the check box "Fractional character
widths" for the "General" preferences (see below for elaboration).  Also,
in MacDraw Pro, you can check alignment best if you zoom in to 400%.

> Having used Mac Draw II, Mac Draw Pro, Claris Works (versions 1&2) 
> Claris Impact and Cricket Draw (version 2), all these programs seem to
> give the same result, i.e. that a drawn object aligned with some 
> characters on the screen does not print in the same relative position, 
> unless the alignment is done at the nominal 100% magnification, 
> or whatever zoom level the printer uses (e.g. my old PaintWriter uses 
> 250% as its base, condensing the result to get a better typeface). 
> In some programs the effect is more marked than others. It does not 
> seem to be related to printing, as you can get the same effect by 
> zooming in, doing the fine placement of the box/line/arrow/whatever, 
> and zooming out again to 100%: things won't look quite the same.
> The problem also appears if you try to align characters in two text 
> objects, especially at the right hand end of the text objects. I have 
> had the same effect using Freelance-For-Windows, a PC program, so it 
> isn't just Macs.
> 
> I would be *very* interested to know if there is a solution to this 
> problem, which seems to be related to the way the programs "magnify" 
> text.(BTW, True-type fonts were used in all my work, but I seem to 
> remember having the same problem with the Mac years ago when I had 
> System 6 and bit-mapped fonts; I also tried removing the TT fonts and 
> forcing the programs to use bit-mapped fonts - it didn't help).

Some of these problems can be traced to certain peculiarities in the way
fonts are drawn on the Macintosh screen and printed on the page.  In order
to preserve "What You See Is What You Get" (WYSIWYG), the printer driver
will try to figure out what font, bitmap, TrueType, or PostScript, was used
for drawing to the screen, then "adjust" the positions of individual
characters on the page to match the positions on the screens.  Sometimes
the result of this adjustment is that you don't always get what you see. 
This is a problem because the widths of the characters (the metrics) are
often different for a bitmap font compared to a TrueType or PostScript
font.  Since a bitmap font is used preferentially for drawing on the
screen, the printer driver will adjust the the positions of the characters
on the page to match the positions on the screen.

There are certain things you can do to minimize this problem.

First of all, if you have TrueType or PostScript fonts, eliminate all
bitmap versions of those fonts.  Unfortunately, this means the fonts won't
look as good on your screen, but it insures that the same font is used for
drawing on the screen and on the page.

Second, turn off Font Substitution in the "Page Setup..." dialog.  When
this is checked, Courier is substituted for Monaco, Times is substituted
for New York, and Helvetica is substituted for Geneva.  Unfortunately,
especially in the case of Helvetica and Geneva, the two fonts will have
different metrics for each character.  The printer driver then spaces the
individual letters differently, for example trying to space the Helvetica
characters on the page to match the positions of the Geneva characters in
the document.  The result is uneven spacing.

Third, whenever possible (and this depends on the program), turn
"Fractional Widths" or "Fractional Character Widths" on.  This allows the
program to take advantage of the greater resolution available on the page
(300 to 600 dots per inch, depending on the printer) compared to the screen
(72 dots per inch).  This setting also tells the system software to use the
metrics for the TrueType or PostScript font instead of the metrics for the
bitmap font, rather than the other way around.  For example, in MacDraw
Pro, if you don't turn Fractional Character Widths on, you will have
problems using Courier 9-point or 12-point when you mix bold, italic, and
roman characters on the same line.  (10-point seems to work fine no matter
what fractional widths setting you use.)

Fourth, for DNA sequence, protein sequence, or any text for which you want
to maintain vertical alignment of the characters, you must use a
mono-spaced font, that is, a font in which all characters have the same
width.  The two most common mono-spaced fonts on the Macintosh are Monaco
and Courier.  I recommend that you always use Courier for drawing and
printing since Monaco has some metrics problems of its own.

-- 
Conrad Halling
Computational Molecular Biologist
Monsanto Co., St. Louis




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