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Re: ElevationGrid

Hi Neil,

You're quite correct.

Neil Woodhouse wrote:

> Hi,
>
> I put on fireproof clothing, get hold of a very large cat, throw it amongst the pigeons and say:  :-)
>
> ...
> If i read the spec right do i take it that the 0,0 co-ord is the top-left of the data set?. If this is the case then for British Ordnance survey maps the ElevationGrid ain't much use.
>
> Does the same problem exist for the DEM. How is this got around.

Build a coordinate conversion (bi-directional of course), and then grumble.It is sub-optimal for DEMs for the same reason.

> Contouring. How can this problem be tackled. Do i have to use the IndexLineSet, if so this means that i have to enter the main data set TWICE!!! and is VRML capable of contouring anyway. It's not mentioned at all!!.

We have done this using texture mapping (which defaults to 2D) but which we utilize in 1D.If you tried an ILS you would probably find your contours diving in and out of the surface, unless
the ILS (contour) data is as course as the grid, which is unlikely.

> Not all of us are interested in making imaginary worlds where scale doesn't matter.

Amen!
Best regards,

Mike Abernathy
Rapid Imaging Software, Inc.
(505) 265 7020
http://www.landform.com/