Re: [Plplot-devel] Re: Important change to unicode text handling in core

[Alan W. I. <ir...@be...>]

On 2005-05-10 09:47-0300 Thomas J. Duck wrote:

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> Hi,
>
>     A plea for help is below.
>
>     Fixing difilt usage for PLESC_HAS_TEXT text handling has opened up a
> whole can of worms.  As I have stated before, the difilt operation for
> text positioning belongs in the core (plP_esc, to be precise) and not in
> driver code, because we need consistency with the other core operations
> (e.g., line drawing).  Proper device filtering is essential to get the
> right results from the plot buffer.
>
>     I have removed the difilt operation from ps.c and plfreetype.c.  So,
> any drivers that use plfreetype.c may be affected.
>
>     The results look good for both the PS and GD drivers in the standard
> orientation.  However, when -ori 1 is used, the text placement in the PS
> driver is not quite right.  Presumably this is due to some kind of
> compensation in the PS driver for the former use of difilt in that code.
>
>     For the GD driver, the placement of symbols in x01c also isn't quite
> right for -ori 1.  This might be related to the adjustment for the
> decender in plfreetype.c.
>
>     Could the people familiar with the text placement code in those
> drivers please apply a fix?  I have a hard time understanding what is
> going on in those routines.
>
>     I'm sorry for making this work, but the change to how difilt is
> applied was really quite necessary.  If nobody wants to try to fix those
> things, then I will do it myself, although it will likely take me more
> time.
>
>     I have already had one email indicating that 5.3.1 can't go ahead
> with this problem.  So, please let me know if there is help, or whether I
> am on my own (copy me at "tom dot duck at dal dot ca").

I am the one that complained off list to Tom yesterday as soon as I
discovered the problem.  I believe this issue is release critical because it
makes both my png and psc FreeEOS research plots (most of which are done
with -ori 1) look bad, and I assume a small but nevertheless significant
fraction of our users are also using -ori and will also therefore dislike
the current state of our code. So I would like to add my voice to Tom's
calling for help from those who have worked before with unicode text
placement for the ps.c and gd.c devices.

Alan
__________________________
Alan W. Irwin
email: ir...@be...
phone: 250-727-2902

Astronomical research affiliation with Department of Physics and Astronomy,
University of Victoria (astrowww.phys.uvic.ca).

Programming affiliations with the FreeEOS equation-of-state implementation
for stellar interiors (freeeos.sf.net); PLplot scientific plotting software
package (plplot.org); the Yorick front-end to PLplot (yplot.sf.net); the
Loads of Linux Links project (loll.sf.net); and the Linux Brochure Project
(lbproject.sf.net).
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