Collision - Physics / Cylinder converts to Z-axis ?

[acocq]

OK, maybe I'm just doing something wrong here, but when I set up a collision (the object has two ... one box, one cylinder) cylinder and set the axis to Y, it shows up properly, but when I test the physics, it always seems to go back to a "Z axis" orientation.  And unless I set it to "Z axis", the object topples over   

The BOX collision is at the "base" of the object (basically a thin square) and has a mass of 10.  The cylinder needs to "stand on" the base and has a mass of 0.1 ... the length of the cylinder is about the length of one side of the square base.

I've gotten around this issue by using a couple of spheres instead of the cylinder, but am just wondering if it is something I goofed up.

Cheers,
Andreas

[acocq]

*BUMP*

[pixel_legolas]

hm, don't really know what is happening, do you mind sharing a file or such?

[BigDaz]

I think cylinders are just broken all round, I wouldn't use them.

[acocq]

I think cylinders are just broken all round, I wouldn't use them.

Say what ?  That would imply that the implementation of the physics engine is faulty ...

Somebody from Helios ... please tell me it isn't so ...

[acocq]

hm, don't really know what is happening, do you mind sharing a file or such?

I'll try to take some screenshots tonight to show what is happening ... but it's really quite easy to try out:

For a given object, create TWO collision shapes for example a cyclinder and a box ... like this:

   |**|
   |    |  <- Cylinder Collision Shape
   |    |
   |    |
   |    |
   |    |
   |__|
_______
|            |  <- Box Collision Shape
-----------

I noticed that the underlying mesh object will flip on its side, unless I set the cyclinder's axis to Z ... in which case it seems to rest on its side, which is no good either.

[pixel_legolas]

Hm, I will try it tonight. Is it a heavy model? Else you can use render object or create a low poly shape of the outer shape and use that as collision

[acocq]

Hm, I will try it tonight. Is it a heavy model? Else you can use render object or create a low poly shape of the outer shape and use that as collision

It's not a really heavy model per se ... the box collision shape has a mass of 15 (KG ?) and the cylinder 0,75 (KG ?), because I wanted to object to be stabilized and rest on the ground (using the box as a base).

I've used simplified versions of mesh objects as collision shapes for most of my objects ... and I use the same approach for creating occlusion objects  ... so yes, that does help somewhat, but it doesn't address the question as to whether or not something is broke in the ODE implementation.

Cheers,
Andreas

[Jim]

I noticed this too.

[gekido]

ODE's cylinder's are pretty broken, have been for years.

[Jim]

Is there anything Helios has planned to resolve this in the future, or is it only waiting on ODE?