Detecting Collision even tough objects are not colliding?

Hey @all!

First of all, have a look at the image:

A and B are Compound Collision Shapes, consisting of a box and a cylinder; 1 and 2 are those cylinders.
When I add A to the physics space and then B, bullet tells me to watch out because of a static-static collision (those shapes are kinematic).

When I run tests without the cylinders 1 and 2, everything works fine.
It works fine as well, when I move the cylinders faaaar away or when I make them very small.
I’d like them to have a radius of 0.73, but in order to not have a collision I have to make them 0.2.

Has anyone an idea why it says they are colliding?
Because on the picture, they’re clearly not.
Thanks in advance!

I can’t edit the first post somehow…
Anyway, here is the image:

What is it that “says they’re colliding”? What are they colliding with?

I might’ve been unclear:

I can add the objects manually; at first neither A or B exist. When I add A, everything is fine.
But when I add B (after having added A), I get this output in the console:

warning CollisionDispatcher.needsCollision: static-static collision!

Therefore I guess A and B have to be colliding in some way.
And because I tried it without the cylinders or with smaller cylinders and it works, I thought it has to be them colliding with each other.

It’s just a debug warning, it’s been around a long time :slight_smile:

https://code.google.com/p/bullet/source/browse/trunk/src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp?r=2621#178

@jmaasing said: It's just a debug warning, it's been around a long time :-)

Google Code Archive - Long-term storage for Google Code Project Hosting.

hm, what is ‘just a warning’?
When I check wether the objects collide, will bullet tell me they collide or not?
Because it’ll get important for me later in development wether they collide.

Of course I could implement that now and test it directly, but I don’t have time until evening.

It’s a warning because the dispatcher is able to recover cleanly. It’s likely your application will work as intended in spite of it.