[ODE] dHeightfield collider

[Martijn Buijs]

Piotr Obrzut wrote:
> Hi,
> 
>    anything new in this topic, anyone planning to add this before new
>    release?
> 

Sorry, haven't been able to spend much time on it lately (working on it in my spare time now, it was 
decided to drop ODE from our project). I'll see what I can do this week, otherwise I will just post 
what I've got so far.

Geoff's solution to the Y-up/Z-up problem sounds like an interesting option, but I'm not a math whiz 
at all, not sure I'll be able to do that.

 > Second, make sure you support variable terrain interpolation methods.

Sounds useful and interesting, but since that will require some changes to the actual collider code, 
I rather leave this to others. Perhaps it is a good idea to expose this with a GetHeight callback 
that specifies the relative X,Z (or X,Y) coordinates as floats rather than ints.

 > One case to consider is where the terrain data is stored in a non-float format in the application

Right now it supports floats and bytes, but I will add 16-bit format as well. Most real world data 
sets (such as those from the USGS) are in a 16-bit format so it is convenient support that. The 
callback interface can be used for other (compressed) formats if needed.

Martijn