/// Set the active state of the body. An inactive body is not
/// simulated and cannot be collided with or woken up.
/// If you pass a flag of true, all fixtures will be added to the
/// broad-phase.
/// If you pass a flag of false, all fixtures will be removed from
/// the broad-phase and all contacts will be destroyed.
/// Fixtures and joints are otherwise unaffected. You may continue
/// to create/destroy fixtures and joints on inactive bodies.
/// Fixtures on an inactive body are implicitly inactive and will
/// not participate in collisions, ray-casts, or queries.
/// Joints connected to an inactive body are implicitly inactive.
/// An inactive body is still owned by a b2World object and remains
/// in the body list.
public void SetActive(bool flag)
{
Debug.Assert(m_world.IsLocked() == false);
if (flag == IsActive())
{
return;
}
if (flag)
{
m_flags |= BodyFlags.e_activeFlag;
// Create all proxies.
b2BroadPhase broadPhase = m_world.m_contactManager.m_broadPhase;
for (b2Fixture f = m_fixtureList; f != null; f = f.m_next)
{
f.CreateProxies(broadPhase, m_xf);
}
// Contacts are created the next time step.
}
else
{
m_flags &= ~BodyFlags.e_activeFlag;
// Destroy all proxies.
b2BroadPhase broadPhase = m_world.m_contactManager.m_broadPhase;
for (b2Fixture f = m_fixtureList; f != null; f = f.m_next)
{
f.DestroyProxies(broadPhase);
}
// Destroy the attached contacts.
b2ContactEdge ce = m_contactList;
while (ce != null)
{
b2ContactEdge ce0 = ce;
ce = ce.next;
m_world.m_contactManager.Destroy(ce0.contact);
}
m_contactList = null;
}
}
/// Destroy a fixture. This removes the fixture from the broad-phase and
/// destroys all contacts associated with this fixture. This will
/// automatically adjust the mass of the body if the body is dynamic and the
/// fixture has positive density.
/// All fixtures attached to a body are implicitly destroyed when the body is destroyed.
/// @param fixture the fixture to be removed.
/// @warning This function is locked during callbacks.
public void DestroyFixture(b2Fixture fixture)
{
if (fixture == null)
{
return;
}
Debug.Assert(m_world.IsLocked() == false);
if (m_world.IsLocked() == true)
{
return;
}
Debug.Assert(fixture.m_body == this);
// Remove the fixture from this body's singly linked list.
Debug.Assert(m_fixtureCount > 0);
b2Fixture node = m_fixtureList;
bool found = false;
while (node != null)
{
if (node == fixture)
{
node = fixture.m_next;
found = true;
break;
}
node = node.m_next;
}
// You tried to remove a shape that is not attached to this body.
Debug.Assert(found);
// Destroy any contacts associated with the fixture.
b2ContactEdge edge = m_contactList;
while (edge != null)
{
b2Contact c = edge.contact;
edge = edge.next;
b2Fixture fixtureA = c.GetFixtureA();
b2Fixture fixtureB = c.GetFixtureB();
if (fixture == fixtureA || fixture == fixtureB)
{
// This destroys the contact and removes it from
// this body's contact list.
m_world.m_contactManager.Destroy(c);
}
}
if ((m_flags & BodyFlags.e_activeFlag) != 0)
{
b2BroadPhase broadPhase = m_world.m_contactManager.m_broadPhase;
fixture.DestroyProxies(broadPhase);
}
fixture.m_body = null;
fixture.m_next = null;
fixture.Destroy();
--m_fixtureCount;
// Reset the mass data.
ResetMassData();
}