[x3d-public] ElevationGrid for the modern age

[Michalis Kamburelis]

Dave A wrote:
> I'm working on an X3D/X3DOM exporter for Unity. Currently working on
> Terrains (ElevationGrids)

I was thinking about extending ElevationGrids for terrains in Castle
Gamer Engine :)

Besides Unity, I would advice looking at World Machine, see e.g.
http://www.world-machine.com/ and
https://www.world-machine.com/learn.php?page=workflow&workflow=wfunity .
Being able to get such assets into X3D, and having the necessary
features in X3D standard, would be very cool!

To store the weights, I would much prefer to keep them as channels in an
image, instead of encoding them as a sequence of floats. (As a sidenote,
I would prefer to have heights encoded in a texture too. With 16-bit
lossless image formats, like png, this is not a problem.) Standard Unity
terrain allows to mix 8 textures, weights are stored inside RGBA
channels in what is called a "splatmap". So with 1 splatmap you have up
to 4 texture weights, with 2 splatmaps you have up to 8 texture weights
(and Unity doesn't support more --- although we probably should not pose
limit in X3D).

Besides coloring the terrain with textures, textures may also be used to
store the density of grass on terrain. And then, one would like to
connect stuff like trees on a terrain, to be able to render them with
instancing... But that's for another time.

Regards,
Michalis