DRAPE IMAGE OVER DEM

Pardon our ignorance: Is there a grass command to drape an image over
a dem when the dem is represented by several files, because it is large?
We have TM data to drape over a dozen or so USGS quad dems, and we'd
prefer not to have to generate the combined dem. Is this a problem for
other folks?

As far as I know, you will have to patch your dems together if you want to use
them in d.3d; it requires a single raster layer. You might consider using
a coarser resolution when you patch them (i.e., change the resolution of
your region to, say, 100 meters, and then run r.patch). This would save
significant space, and would probably still be acceptable for creating 3d
images.
--
Malcolm D. Williamson - GIS Specialist E-mail: malcolm@cast.uark.edu
Center for Advanced Spatial Technologies Telephone: (501) 575-6159
Ozark Rm. 12 Fax: (501) 575-5218
University of Arkansas
Fayetteville, AR 72701