Re: Height maps

steve ([email protected])
Wed, 10 May 1995 09:59:19 GMT0BST


> Except that (...and correct me if I'm wrong) the advantage to the node
> specified by Jim is that you ONLY SPECIFY Z ELEVATIONS. This cuts down
> the amount of data that needs to be transmitted by 2/3 (a single float
> per specified point instead of 3 floats per point). This is neither a
> tri-mesh or a quad-mesh. This type of node is easily generated from dem
> and other forms of publically available terrain data.

I agree. These HeightMaps are useful for terrain simulations etc.
where you can get away with a regular grid. The browser can mesh
this how it likes - you can even skip over grid points to give some
crude form of level of detail. These should be considered in a
different light to tri and quad-meshes - height maps assume a planar
base. standard tri and quad meshes can assume any 3D shape, as each
vertex includes a full 3D coordinate.

The height map vertex should also support color definition and a
texture coordinate - amazing terrain maps can be achieved by mapping
a monochrome texture (grass-like) onto a pre-colored surface.
Cooking the vertex colors according to height can give nice effects
like snow-capped mountains.

I would also like to put in my vote for include both tri-mesh and
quad-meshes in future revisions. Anything to get the complexity down
and the speed up.

>>-------------------------------------<<
Steve Ghee ( [email protected] )
Director of Technology

Division Ltd
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