Project with GRASS. Help!!

[Alejandro Imass]

Carlos Martinez wrote:

> Hi.
>
> First of all, sorry for my english. I don't speak english very well, but I
> need some help about GRASS and I don't find spanish people that develop
> applications with it.
>
> I'm working in a project to manage archeologic excavations. In this
> project I have to manage the objects found on the ground when the
> excavation is done. I have some problems because I'm beginning in GRASS
> and GIS world.
>
> There are three type of objects that can be found in the excavation. The
> first and more important are the geological layers. The second are the
> objects builded by the humans like walls or houses. The third are the
> rests of dead people. The last two types of objects are less important
> because I think its imposible to handle them in a GIS in other way that
> with sites.
>
> The problem is the firs type. In the project that I'm developing the
> objects corresponds to the space of the same material, not to the
> limit of this material. I have done a DEM introducing points with x, y and
> z coordinates. But the problem is that this DEM corresponds to one of
> the two limits of one object. I have done this because one of the work of
> the archeolegs is to give points from the ground to make a map after.
>
> Despite of this the problem is that is posible to find an object of one
> material inside an object of another material. I don't know how to do
> this. To do this I need to develop a system in wich the limit between two
> objects is had to be clear. Two layers can be considered two surfaces
> interpolated from sites, wich z value is the height from an horizontal
> plane, but the object between them...
>
> I have seen that there is a type of data in GRASS called G3D from wich a
> good aproaching can be done. Do you know something about it? Can I use it
> to do the application? Do you know where can I find some information?
>
> In http://www2.gis.uiuc.edu:2280/modviz/gsoils/ccsoil2.html I have seen
> some pictures like the thing I want to do. The difference is that I want
> to do that with ground.
>
> Other thing is that in an excavation can be found a lot of ground layers.
> If one ground layer of one material corresponds to two raster layers and I
> can find a lot of them, is it posible to have problems because a lot of
> layers are needed?
>
> Another problem is that I want to assign some attributes to
> each object of the excavation. It's easy if the objects are of the two
> last types because they are sites. The problem is if the object is a
> ground layer. How can I do it? How can I add fields to the object? How can
> I link it with the database table, with cathegory or with coordinates? I
> don't know how Postgress/GRASS interface does it. I need to develop the
> system without any data, introducing points of the ground, so I can't use
> an ArcView shapefile. How can I do it with the Postgres/GRASS interface?
>
> The archeolegs need to work at really small scales, perhaps to 1:10 or
> 1:5, because they need to manage small objects with good precission. Is it
> possible to have problems because of that? Is a good idea to use a GIS to
> develop the project?
>
> Thanks and sorry for my english again. If I could explain myself in
> spanish I think this letter could be better.
>
> Thank you again.

A pesar de no ser un experto en GIS conozco mas o menos el paquete y te puedo
ayudar en el funcionamiento, pero no en la parte 3D. Sin embargo, estaría
feliz de aprender, e intermediar entre la lista y tu persona. Si necesitas
que ayude a traducir cualquier problema sólo déjamelo saber. Mientras tanto
voy a tratar de entender tu mail con calma :-)

Saludos,
Alejandro Imass
aimass at net-a1.net