[GRASS5] all the DXF modules...

[Helena]

"Roger S. Miller" wrote:

> Markus Neteler wrote:
>
> > But first: I have added DXF layer output to v.in.dxf.
> [snip]
> > I think that's useful.
>
> I think that's a great addition, Markus.
>
> [snip]
> > Maybe it would make sense to merge v.in.dxf and v.in.dxf3d with
> > an optional flag for the Z value. And what about v.cadlabel...?
> >
> > Comments and volunteers would be welcome.
>
> I think combining the v.in.dxf* files is a good idea.  v.cadlabel
> performs a pretty unique function.  I don't have a use for it and
> wouldn't expend any effort supporting it.  v.import and v.export have
> DXF functions and I think those should probably be removed.  The reason
> is that the DXF format is important and difficult to support.  It needs
> to be supported through a specialized set of programs.  Supporting DXF
> import and export through additional generic tools like v.import and
> v.export seems to me like an unnecessary added work load.
>
> We had a thread about DXF imports last spring.  Unless things have
> changed in more recent rewrites there are several problems with the
> existing import routines.  There are several object types that they
> don't import; in particular, they don't import text or splines.

I am not sure whether this would be of any help, it depends on how
splines are defined in DXF, but there are spline functions for curves
used in few GRASS modules, e.g. v.to.sites (to generate additional points
on a curve if the given points are too far apart) and SG3d (and probably
nviz)
to define the fly path, so to write support for import of splines may be
simplified by
using these functions, they work pretty well.

> They
> don't import text on arcs either, but maybe that's too much to expect.
> There are probably other data types that aren't imported.
>
> I've written my own import routines for DXF->grass ascii vector and DXF
> text->paint labels, but I doubt that my routines are sufficient for the
> future needs of GRASS.
>
> There is at least one third-party import/export library released under
> the GPL.  The one I know if is DIME, which is a C++ class library.  I'm
> not very comfortable programming in C++.  Also, I don't have much time
> to spare right now and we will probably be into next year before I do.
> Just the same, when time is available I will be willing to help.
>
> Roger Miller
> _______________________________________________
> grass5 mailing list
> grass5 at grass.itc.it
> http://grass.itc.it/mailman/listinfo/grass5