[ODE] Re: Heightfield / Collision.

[Amund Børsand]

"gl" <gl@ntlworld.com> skreiv:

> (copy to the right place):
> 
> > First off, I don't much appreciate the tone of your reply.  Whatever upset
> > you, you're taking this way too personally...

First off, who is talking to who now? And what is it really that someone
wants and don't want? Is it really "their" discussion, and if so, I'm
sorry for barging in. But if it was a strictly private discussion where
people weren't supposed to reply, why is it posted here? (This is not
for you, GL, but for whoever you were replying to)


> > Also, you generally _want_ your collision response to follow your visual
> > output.  Consider the case of interpolation over a large triangle in a
> > low-res map - do you really want to see objects hover over its center?
> For
> > most cases, you do want the triangle output and collision data to match
> up.

What I thought was just that while you might use gouraud shading or
something to smooth out the terrain, you could use interpolation to
smooth out the terrain for the collision detection. This could be useful
both for high and low res maps, but mostly for driving stuff on the
terrain, I guess.. driving over smooth curves probably feels better than
driving on flat flakes with sudden angles between them. But it all
depends on what you're using it for, you are probably using it for
something else than what I'm thinking about =)

> > > And that is exactly why I tend to oppose the notion, that collision
> > detection solutions should primarily be based on rendering issues. I
> thought
> > I just read a post from gl saying that the aim was a flexible, generic
> > solution. If that solution is targeted at colliding with tri-meshes, then
> > I'm barking up the wrong tree with my comments here. But if the solution
> is
> > targeted at colliding with heightfields then I'd submit that using
> triangles
> > is not the way to go about it.


> > > I don't see how parking garages and tunnels have anything to do with
> > heightfields. The main point of a heightfield is that they don't have
> > multiple levels. Why not try incorporating a BSP-tree collider while
> you're
> > at it? Excuse me for being so blunt, but I'm starting to wonder what the
> aim
> > is here. I thought ODE was a physics simulation library aiming for
> realtime
> > performance, stability and reasonable accuracy. But now it looks like it's
> > being molded into a gaming engine.

That was something really scary to say. What do *you* think we should
use ODE for? I never noticed a list anywhere of things you're not
allowed to use ODE for (like Dell laptops, which are forbidden to use
for developing weapons of mass destruction (you have to sign for that
when you order one)).