Collision Flags

[Archeron]

Hi, by using bullet library I found a strange thing about collision flags. I show you an example of the problem i got :

So first I create a rigid body :

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btRigidBody* Body = new btRigidBody(//some stuff);

then my own collision flag and filter :

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short COL_TEST  = 1<<5;
short FLT_TEST = COL_TEST | CF_STATIC_OBJECT;

and to finish I add my Body to the world with the collision flag and filter :

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World->addRigidBody( body, COL_TEST, FLT_TEST );

Later in the code I use the ghostObject of my kinematicCharacterController, it collides fine with the body I created by respecting the collision flag and filter. But when I want to compare the flag of the btCollisionObject with my collision flag, like that :

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If(GhostObject->getOverlappingObject(i)->getCollisionFlags() == COL_TEST)

It is always false because it is not the good value. I need to set the collision flag of my Body to have the result I expect :

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World->addRigidBody( body, COL_TEST, FLT_TEST );
Body->setCollsionFlag(COL_TEST);

Without this instruction I can’t know when I have a btCollisionObject with my personnal collision flag. It is very strange because Bullet know what is the collision flag and if it is not in the filter of my kynematic character, I don’t have physic collision with it.
But when I want to get the collision flag it is not the good value, I need to add the collision flag in an explicit way to get the good value for the flag.

So, what are your feelings about this ? May be it is normal but it looks very strange for me.
If you want more details I can provide them, just ask .

[betacub]

This interface is setting the collision filter group and mask, respectively, not the collision flags and filter:

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World->addRigidBody( body, COL_TEST, FLT_TEST );

To set collision flags, you have to call the method on the body directly, as you identified yourself:

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Body->setCollisionFlags(COL_TEST)