curve surfaces & elevation map

I am trying to make an engine for fast terrain rendering.
My idea is to use bezier patch (with central differencing & light map), and to also use an elevation map to add both noise and more realistic effects (such as more sharp hill).
Do you think it’s a good way to make all that stuff?
Have you ever heard of guys using the same idea??

I think it’s a good idea since I’m working on a Octree/Portal based 3D engine using that kind of stuff.

With that kind of things you would get easy MRM/Dynamic LOD, and get nice looking terrains.

If you’re interested in working on such an engine, I’m looking for some help.
The engine I’m working one must be used in Awakening (Thrilling/Fantastic adventure game), Hypernovae (, and my very own Fedia: Legend.

Notice that I haven’t start programming it yet, I’m looking for good illumination and shadowing technics.
(I already recoreded 6 way to do that but none is good to me.)

[This message has been edited by Ingenu (edited 07-25-2000).]

Yes, we are rendering terrain using the technique like yours.
It looks great.
(I think “elevation maps” mean the Sim Dietrich maps?)

what are Sim Dietrich maps??
do you know good articles about noise map and/or elevation map??
another question : don’t you think that bezier patch doesn’t give enough freedom, since that if you want to have a C1 continuity (between the patch), the half of the patch control points are pre-determined?

  1. Really I don’t using plain old Bezier patches. I’m using prebuilt adaptively tesselated NURBSes.
  2. Elevation maps:

Thank u for the link!
Sorry for asking you a lot of questions, but what are the particularities of your nurbs??
Do you have a recursive algo like “central differencing” do draw them (as nurbs are rationnal, I don’t see how to make an efficient teslation algorithm…)??
thx a lot