[GRASS-dev] discussion: replacing ps.map

[Roger Miller]

On Thu, 2007-03-29 at 18:51 +1200, Hamish wrote:
> roger wrote:
> > ps.map does a better job of placing labels than does d.paint.labels,
> > which is basically broken -- at least in 6.2.
> 
> please explain? bug #? what is broken with d.labels? (note rename)
> If it is broken I will try and fix it. AFAIK it has been working well
> since GRASS 6.1.0.

Rotated labels appear in incorrect locations.  The rotation is correct.
The same labels plotted with ps.map appear in the correct locations.  I
have not noticed the same problem with unrotated text.  In my case, the
labels are contour labels produced by Surfer.  Text data from a dxf file
are used to create a paint labels file.

My problem is with 6.2.0beta3, so there is the possibility that it is
already fixed.

> > ps.map uses the same icons that are used by the GRASS vector routines.
> > This is not a problem in ps.map, but a limitation that effects all
> > GRASS displays.
> 
> So are you saying here that GRASS icons(symbols) could be improved?
> or asking another way: what is the limitation? what is bad about them?

I think the symbols we have are fine.  What we have now is a vast
improvement over previous versions.  We just need to provide more of
them, either in the standard distribution or in downloadable packages.
In my field (I'm a hydrogeologist) there are probably more than a 100
fairly standardized point symbols in common use.  I recently printed out
pages of data on the USGS map symbology with the hopes that I would have
the time to build at least part of that set.  That much time is hard to
come by.

> > I agree that ps.map support for legends is not very good.
> 
> do you mean raster categorical legends, raster floating point legends,
> or vector legends? what do you miss?

Any of the above and more.  My specific and recurring problem is with
symbol keys.  The two built-in facilities for legends (the colortable
and vlegend) are not configurable enough to be generally useful.

Fixing the limitations with legends is a pretty big task -- especially
since there are so many different kinds of legends.  Legends can be
built manually in ps.map or they can be imported as eps files, so I
don't know that I would put the legend problem very high on a priority
list.


Roger