[GRASS5] NVIZ updates

[Bob Covill]

Helena,

I have applied a fix to CVS that corrects (hopefully) the NVIZ bug you 
reported.

The problem was with surfaces being loaded that contained no null values 
.  The new coarse surface (wire) routine was causing a crash. Apparently 
if a null mask is created it is much more forgiving if one isn't (i.e. 
no nulls).

The fixed gsd_wire.c in src/libes/ogsf should correct the bug.

To test update your ogsf and rebuild NVIZ.

Let me know if you encounter any more problems, etc.

Thanks for catching this.

--
Bob Covill