[Solved] Ogre3d + Bullet - Sphere not rolling

[joaopccosta]

Hi,

I have the following problem. I am using Bullet with Ogre in order to create a bowling game.
All the physics are perfectly fine except for one thing... When I throw the ball, it doesn't roll. In fact, it seems to slide over the bowling lane... I have tried using different method to apply impulse on the ball, fiddled with the physical properties, double checked that I am creating the correct btCollisionShape, and nothing seems to change it.

Sphere shape and SceneNode creation:

Code: Select all

// Create shape in my Physics Manager class
// ...
btCollisionShape aBall = new btSphereShape(1.5f);
createBall("ball", Ogre::Vector3(1.5f, 1.5f, 1.5f), Ogre::Vector3(0,1.5f, -1*(arena_measures.z/2)+10), 200.0, aBall); 
// ...

void CriterionBowling::createBall(const char *name, const Ogre::Vector3 &size, const Ogre::Vector3 &pos, float mass, btCollisionShape &shape)
{
	// Create ogre scene node
	Ogre::SceneNode* node1 = mSceneMgr->getRootSceneNode()->createChildSceneNode(name);
     
	// Create our rigidboy using our Bullet Wrapper
    btRigidBody &body = mPhysics.createBody(btTransform(btQuaternion::getIdentity(), btVector3(pos.x, pos.y, pos.z)), mass, shape);
	// Set some physical properties
	//...
	
	// Add it to our bowling simulation
	mBall = new Ball(*node1,body);
    
    // Get its mesh 
    Ogre::Entity *entity = mSceneMgr->createEntity(name, "sphere.mesh");
    // Give it a texture
    entity->setMaterialName("BowlingBall");
    node1->attachObject(entity);	
}

So I guess I'm doing everything right until here... correct?

Bowling ball throw and update:

Code: Select all

void Ball::throw(const Vector3 force)
{	
	// Lock the ball --> player can't control it anymore
	locked = true;

	this->mRigidBody.activate(true);

	// Apply force to the rigidbody
	this->mRigidBody.applyCentralImpulse(btVector3(force.x,force.y,force.z));	

}
void Ball::update()
{
		// Get Bullet transformation matrix
		btTransform transform;
 
		// Get the transformation of this rigidbody in the transformation matrix
		mRigidBody.getMotionState()->getWorldTransform(transform);
 
		// Obtain the rotation and update the graphical representation
		btQuaternion rotation(transform.getRotation());
		node.setOrientation(rotation.getW(), rotation.getX(), rotation.getY(), rotation.getZ());
		 
		// Update the position
		const btVector3 &origin = transform.getOrigin();			
		node.setPosition(origin.getX(), origin.getY(), origin.getZ());		


}

What about this part?

I have no clue of I might be doing wrong... Could it be the physical properties of the lane floor and/or ball??

Thanks in advance!
Cheers,
Joao

[joaopccosta]

It was a problem with using env_map spherical in the ball's texture_unit in the materials script...