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So, I was using the pre-release of GE 1.5 and was expirementing (spelled that wrong I think xD) with the new physics. A problem that I noticed was that when messing with dynamic and static actors is that I couldn't specify which actors were supposed to collide and which weren't. Like, I wanted two different actors to collide with the ground but not with eachother. Is this possible to change? If not, could it be implemented in the final release?

Thanks, SuperSonic

The physics actors are a class of actor. They all must interact with other physics actors. So currently I don't think there is a way of setting them up to collide with only some of the other physics actors. This in general is more convenient because you don't have to specify all actors to collide with every other actor. I'm assuming you mean that you should be able to add collision events with other physics actors, which causes the actors to interact, yes? Otherwise I don't really see how it would be implemented.

skydereign wrote:I'm assuming you mean that you should be able to add collision events with other physics actors, which causes the actors to interact, yes? Otherwise I don't really see how it would be implemented.

Yeah, isn't their any way we can have the new physics implemented through PhysicalResponse()?

The thing is the physics actors are constantly under the influence of the physics engine. It isn't just the collisions themselves. So you couldn't just isolate it to the PhysicalResponse, though that would have been nice.

Aw darn =/

Is there any chance that we could fix this problem in the future?

Thats a very good point. Is already implemented and should work. You can test this e.g. with the machine example.

As long as we dont have a documentation see here:

http://www.box2d.org/manual.html

and search for "Groupindex":
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Collision groups let you specify an integral group index. You can have all fixtures with the same group index always collide (positive index) or never collide (negative index). Group indices are usually used for things that are somehow related, like the parts of a bicycle. In the following example, fixture1 and fixture2 always collide, but fixture3 and fixture4 never collide.

fixture1Def.filter.groupIndex = 2;

fixture2Def.filter.groupIndex = 2;

fixture3Def.filter.groupIndex = -8;

fixture4Def.filter.groupIndex = -8;
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Oh wow akr. Thank you and +1