[GRASS-user] NViz - problem in the visualization of 3D objects

[Carla Rebelo]

Hi,

I have footprint buildings and the height value (type double
precision) of each footprint.

v.info -t map=buildings@
nodes=250
points=0
lines=0
boundaries=243
centroids=88
areas=89
islands=8
faces=0
kernels=0
primitives=331
map3d=1

After the v.extrude step "v.extrude --overwrite --verbose
input=buldings@ output=buildings3D hcolumn=Height type=area

v.info -t map=buildings3D@
nodes=646
points=0
lines=0
boundaries=0
centroids=0
areas=0
islands=0
faces=743
kernels=88
primitives=831
map3d=1

When I visualized the file 3D from NViz, I have seen some of the
buildings with a black filling (it's black inside or the top of
building is black) ....

Is it a problem of rendering? Or a problem with the topology?

Best regards,
CR