Disabling collision response for some objects

[revelation60]

In my game I have a player, items and a map. I want the items to fully interact with the map, so with collision response enabled. However, I want the items to have no collision response with the player, but I do want the collision to show up in the contact point list. I have tried using masks, but that didn't work because I got no contact point. How do I do this?

[Flix]

Have you tried with the CF_NO_CONTACT_RESPONSE flag ?

Code: Select all

body->setCollisionFlags(body->getCollisionFlags() | CF_NO_CONTACT_RESPONSE)

[revelation60]

Doesn't that disable response for all objects? I still want my items to have a response with the world geometry, only not with the player. I have solved it now by deriving btCollisionDispatcher and adding a check in the needReponse function.

[Flix]

I'm sorry I didn't read your post carefully. Basically it seems you need to use it only for some collisions... and I don't think it's possible as far as I know

[Flix]

I have solved it now by deriving btCollisionDispatcher and adding a check in the needReponse function.

Good to know it's possible

[fido]

Doesn't that disable response for all objects? I still want my items to have a response with the world geometry, only not with the player. I have solved it now by deriving btCollisionDispatcher and adding a check in the needReponse function.

I tried something like that and I 've got stuck with limitation that in btCollisionDispatcher I can filter only whole objects. I needed to filter also certain child shapes in btCompoundShape. I ended up with implementation of 32x32 bit matrix in btOverlappingPairCache and every collision object or child of btCompoundShape can have its own mask. It needed huge changes inside both broad and narrow phase as I needed to pass there these masks. Anyway it works fine and it is configurable in any way.