Re[2]: [ODE] Cylinder class stable?

[slipch]

Hello Olivier,

Thursday, June 26, 2003, 3:15:50 PM, you wrote:

Thank you for your remarks.

OM> improved the capped cylinder to capped cylinder code - it is now shorter
OM> and faster, and it does not have a bug that the old code had where
OM> cap-to-cap contact points would not be detected if the cylinder axes
OM> were parallel.

Now I see Cylinder - Cylinder code is very different from CCylinder - CCylinder.
I do not think they can have same problems. Still I am not sure it
needs some time to understand  CCylinder - CCylinder code.

OM> I am not sure however if this has any relationship with the Cylinder 
OM> Cylinder collision problems. I could observe it when both cylinders have 
OM> the same vertical axis. I can describe the problem as follow:

OM> When two cylinders are set on a floor, lying on one of their flat end 
OM> like this (warning: ASCII art coming up):

OM>       __      _
OM>      |  |    | |
OM>      |1 | -> |2|
OM> _____|__|____|_|____


OM> If cylinder 1 moves towards cylinder 2, the collision is not detected 
OM> when it should. The two cylinders have to interpenetrate each other more 
OM> deeply than necessary before the collision is detected, like if the 
OM> radius of the cylinders were a bit too small when computing collision 
OM> detection...

OM> Anyone else experienced a similar problem ?

I has not reproduce it in my test scene. They seems to collide right.
But remember Cylinder-Cylinder always set only one contact point. It is a problem for
some cases including rather long  parallel cylinders.
Anyway I will examine the case with parallel cylinders. There may be my error.

-- 
Best regards,
Konstantin Slipchenko                        mailto:slipch@gsc-game.kiev.ua