RayTest simple issue

[GripInc]

Hi all,

I have an issue with rayTest: it doesn't add any collision where it should obviously.
I'm pretty sure I am missing something easy.

Here is the minimal code:

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mBroadphase = new btDbvtBroadphase();
mCollisionConfiguration = new btDefaultCollisionConfiguration();
mDispatcher = new btCollisionDispatcher(mCollisionConfiguration);
mCollisionWorld = new btCollisionWorld(mDispatcher, mBroadphase, mCollisionConfiguration);

btCollisionObject* collisionObject = new btCollisionObject();
btBoxShape* collisionShape = new btBoxShape(btVector3(10.f, 10.f, 10.f));
collisionObject->setCollisionShape(collisionShape);
mCollisionWorld->addCollisionObject(collisionObject);

btVector3 testFrom = btVector3(10.f,0.f,0.f);
btVector3 testTo = btVector3(150.f,0.f,0.f);

collisionObject->setWorldTransform(btTransform(btQuaternion(0.f, 0.f, 0.f, 0.f), btVector3(100.f,0.f,0.f)));

btCollisionWorld::ClosestRayResultCallback closestRayResultCallback(testFrom, testTo);
mCollisionWorld->rayTest(testFrom, testTo, closestRayResultCallback);

if(closestRayResultCallback.hasHit())
{
	int i = 0; //Used to breakpoint on
}

Adding to my confusion, a collision is registered if I replace btVector3 testFrom = btVector3(10.f,0.f,0.f); by btVector3 testFrom = btVector3(9.f,0.f,0.f);

Thanks for your help

[Flix]

collisionObject->setWorldTransform(btTransform(btQuaternion(0.f, 0.f, 0.f, 0.f), btVector3(100.f,0.f,0.f)));

What world transform is this ? Maybe you should use btMatrix3x3::getIdentity() as the transform basis.

[GripInc]

Hi again,

I finally got the solution:
I had to update AABB after a collision object has its transform changed.

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collisionObject->setWorldTransform(btTransform(btQuaternion(0.f, 0.f, 0.f, 0.f), btVector3(100.f,0.f,0.f)));
mCollisionWorld->updateSingleAabb(collisionObject);

@Flix: I don't get the point of setting an identity matrix as the object transform. I am doing something wrong in my code?

Thanks for your help

[Flix]

I don't get the point of setting an identity matrix as the object transform. I am doing something wrong in my code?

btQuaternion(0.f, 0.f, 0.f, 0.f) doesn't seem to be a normalized unit quaternion. I would have used something like:

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collisionObject->setWorldTransform(btTransform(btMatrix3x3::getIdentity(),btVector3(100.f,0.f,0.f)));

, but this did not solve your problem .

[bwelch]

I believe a "clear" quaternion would be btQuaternion(0,0,0,1), not btQuaternion(0,0,0,0).