def test_motionstate(self):
"""
Set and get a motion state.
"""
# Get RigidBody object.
body = getRB()
# Create a new Transform.
pos = Vec3(1, 2, 3.5)
rot = Quaternion(0, 1, 0, 0)
t = Transform()
t.setOrigin(pos)
t.setRotation(rot)
# It must be impossible to instantiate 'MotionState' directly.
with pytest.raises(NotImplementedError):
MotionState()
# Create a MotionState and apply the new transform.
ms_ref = DefaultMotionState()
ms_ref.setWorldTransform(t)
# Verify the MotionState does not yet match ours.
ms = body.getMotionState()
assert ms.getWorldTransform().getOrigin() != pos
assert ms.getWorldTransform().getRotation() != rot
# Apply- and query the MotionState.
body.setMotionState(ms_ref)
ms = body.getMotionState()
# Verify the MotionState is correct.
assert ms.getWorldTransform().getOrigin() == pos
assert ms.getWorldTransform().getRotation() == rot
def getRB(pos=Vec3(0, 0, 0), cshape=SphereShape(1)):
"""
Return a Rigid Body plus auxiliary information (do *not* delete; see
note below).
.. note:: Do not delete the tuple until the end of the test
because it may lead to memory access violations. The reason is that a
rigid body requires several indepenent structures that need to remain
in memory.
"""
t = Transform(Quaternion(0, 0, 0, 1), pos)
ms = DefaultMotionState(t)
mass = 1
# Build construction info and instantiate the rigid body.
ci = RigidBodyConstructionInfo(mass, ms, cshape)
return RigidBody(ci)
def moveBody(rb, pos):
trans = Transform()
trans.setOrigin(pos)
ms = DefaultMotionState()
ms.setWorldTransform(trans)
rb.setMotionState(ms)
from azBullet import StaticPlaneShape, SphereShape
from azBullet import DefaultMotionState, Transform
from azBullet import RigidBody, RigidBodyConstructionInfo
# Instantiate the Bullet simulation.
sim = azBullet.BulletBase()
sim.setGravity(Vec3(0, -10, 0))
# Create the collision shape for Ball and Ground.
ballShape = SphereShape(1)
groundShape = StaticPlaneShape(Vec3(0, 1, 0), 1)
# Create the rigid body for the Ground. Since it is a static body its mass must
# be zero.
mass = 0
groundRigidBodyState = DefaultMotionState(
Transform(Quaternion(0, 0, 0, 1), Vec3(0, -1, 0)))
ci = RigidBodyConstructionInfo(mass, groundRigidBodyState, groundShape)
groundRigidBody = RigidBody(ci)
groundRigidBody.setRestitution(1.0)
sim.addRigidBody(groundRigidBody)
del mass, ci
# Create the rigid body for the Ball. Since it is a dynamic body we need to
# specify mass and inertia. The former we need to do ourselves but Bullet can
# do the heavy lifting for the Inertia and compute it for us.
fallRigidBodyState = DefaultMotionState(
Transform(Quaternion(0, 0, 0, 1), Vec3(0, 20, 0)))
mass = 1
fallInertia = ballShape.calculateLocalInertia(mass)
ci = RigidBodyConstructionInfo(mass, fallRigidBodyState, ballShape,
fallInertia)
