// convert square velocity magnitude from IVP to HL
float CPhysicsObject::GetEnergy()
{
IVP_Core *pCore = m_pObject->get_core();
IVP_FLOAT energy = 0.0f;
IVP_U_Float_Point tmp;
energy = 0.5f * pCore->get_mass() * pCore->speed.dot_product(&pCore->speed); // 1/2mvv
tmp.set_pairwise_mult(&pCore->rot_speed, pCore->get_rot_inertia()); // wI
energy += 0.5f * tmp.dot_product(&pCore->rot_speed); // 1/2mvv + 1/2wIw
return ConvertEnergyToHL( energy );
}
float CPhysicsObject::GetEnergy() const {
float e = 0.5 * GetMass() * m_pObject->getLinearVelocity().dot(m_pObject->getLinearVelocity());
e =+ 0.5 * GetMass() * m_pObject->getAngularVelocity().dot(m_pObject->getAngularVelocity());
return ConvertEnergyToHL(e);
}
float CPhysicsObject::GetEnergy() const {
// (1/2) * mass * velocity^2
float e = 0.5f * GetMass() * m_pObject->getLinearVelocity().dot(m_pObject->getLinearVelocity());
e += 0.5f * GetMass() * m_pObject->getAngularVelocity().dot(m_pObject->getAngularVelocity());
return ConvertEnergyToHL(e);
}
//-----------------------------------------------------------------------------
// Purpose: This walks the objects in the environment and generates friction events
// for any scraping that is occurring.
//-----------------------------------------------------------------------------
void ProcessActiveObjects( IVP_Environment *pEnvironment, IPhysicsCollisionEvent *pEvent )
{
// FIXME: Is this correct? Shouldn't it do next PSI - lastScrape?
float nextTime = pEnvironment->get_old_time_of_last_PSI().get_time();
float delta = nextTime - m_lastScrapeTime;
// only process if we have done a PSI
if ( delta < pEnvironment->get_delta_PSI_time() )
return;
float t = 1.0f;
t /= delta;
if ( t > 10.0f )
t = 10.0f;
m_lastScrapeTime = nextTime;
// UNDONE: This only calls friciton for one object in each pair.
// UNDONE: Split energy in half and call for both objects?
// UNDONE: Don't split/call if one object is static (like the world)?
for ( int i = 0; i < m_activeObjects.Count(); i++ )
{
CPhysicsObject *pObject = m_activeObjects[i];
IVP_Real_Object *ivpObject = pObject->GetObject();
// no friction callbacks for this object
if ( ! (pObject->GetCallbackFlags() & CALLBACK_GLOBAL_FRICTION) )
continue;
// UNDONE: IVP_Synapse_Friction is supposed to be opaque. Is there a better way
// to implement this? Using the friction listener is much more work for the CPU
// and considers sleeping objects.
IVP_Synapse_Friction *pfriction = ivpObject->get_first_friction_synapse();
while ( pfriction )
{
IVP_Contact_Point *contact = pfriction->get_contact_point();
IVP_Synapse_Friction *pOpposite = GetOppositeSynapse( pfriction );
IVP_Real_Object *pobj = pOpposite->get_object();
CPhysicsObject *pScrape = (CPhysicsObject *)pobj->client_data;
// friction callbacks for this object?
if ( pScrape->GetCallbackFlags() & CALLBACK_GLOBAL_FRICTION )
{
float energy = IVP_Contact_Point_API::get_eliminated_energy( contact );
if ( energy )
{
IVP_Contact_Point_API::reset_eliminated_energy( contact );
// scrape with an estimate for the energy per unit mass
// This assumes that the game is interested in some measure of vibration
// for sound effects. This also assumes that more massive objects require
// more energy to vibrate.
energy = energy * t * ivpObject->get_core()->get_inv_mass();
if ( energy > 0.05f )
{
int hitSurface = physprops->RemapIVPMaterialIndex( pOpposite->get_material_index() );
CPhysicsFrictionData data(pfriction);
pEvent->Friction( pObject, ConvertEnergyToHL(energy), pObject->GetMaterialIndexInternal(), hitSurface, &data );
}
}
}
pfriction = pfriction->get_next();
}
}
}
