[ODE] static Meshes

[cledwith at d-a-s.com]

Hmm, the docs state that fixed joints are not a good idea:

"The fixed joint maintains a fixed relative position and orientation
between two bodies, or between a body and the static environment. Using
this joint is almost never a good idea in practice, except when debugging.
If you need two bodies to be glued together it is better to represent that
as a single body.

Currently the fixed joint does not support a non-identity relative
rotation between two bodies, it only supports a relative offset."

So how do you keep these bodies all relative to one another? Am I missing
something? My understanding was that you needed to model this as one body
with multiple geoms for collision. In looking at the mass functions again,
it seems like you could feed transforms of these individual geoms
dMassTranslate and dMassRotate to manipulate the inertia tensor to
represent the mass distribution of the body. Though I haven't tried it
myself yet.

-Chris


>
>> In your case, a chair can simply be a box. Or two boxes - the one that
>> bounds chair legs, and the other one that bounds backrest. Simple and
>> fast.
>
> That's strange. I heard the initial request as "a chair falling down some
> stairs".
>
> The absolutely obvious way of modelling this is to turn the stairs into a
> series of boxes, and use a mesh of the chair. This also gives good
> locality, as you won't test the entire stairs against the chair each frame
> (bounding volume test will discard most steps). Then, create the inertia
> tensor of the chair by adding a bunch of box bodies (not geoms!) for the
> legs, seat and back.
>
> Cheers,
>
>                         / h+
>
>
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