C++ (Cpp) getLateralVelocity示例

示例#1

文件： box2d_vehicle.cpp 项目： hydren/carse

void Box2DVehicleBody::Tire::updateFriction() {
	//lateral linear velocity
	b2Vec2 impulse = m_body->GetMass() * -getLateralVelocity();
	if ( impulse.Length() > m_maxLateralImpulse )
		impulse *= m_maxLateralImpulse / impulse.Length();
	m_body->ApplyLinearImpulse( m_currentTraction * impulse, m_body->GetWorldCenter() , true);

	//angular velocity
	m_body->ApplyAngularImpulse( m_currentTraction * 0.1f * m_body->GetInertia() * -m_body->GetAngularVelocity() , true);

	//forward linear velocity
	b2Vec2 currentForwardNormal = getForwardVelocity();
	float currentForwardSpeed = currentForwardNormal.Normalize();
	float dragForceMagnitude = -2 * currentForwardSpeed;
	m_body->ApplyForce( m_currentTraction * dragForceMagnitude * currentForwardNormal, m_body->GetWorldCenter() , true);
}

示例#2

文件： CarModel.cpp 项目： flair2005/carvatar

void CarModel::updateFriction() 
{
	//calculate the counter lateral impulse based on drift parameters
	b2Vec2 impulse = m_body->GetMass() * -getLateralVelocity();
	if (impulse.Length() > m_maxLateralImpulse)
		impulse *= m_maxLateralImpulse / impulse.Length();
	// apply the impulse
	m_body->ApplyLinearImpulse(m_driftFriction * impulse, m_body->GetWorldCenter(), true);

	//angular velocity
	m_body->ApplyAngularImpulse(m_angularFriction * m_body->GetInertia() * -m_body->GetAngularVelocity(), true);

	//forward linear velocity
	b2Vec2 currentForwardNormal = getForwardVelocity();
	float currentForwardSpeed = currentForwardNormal.Normalize();
	float dragForceMagnitude = -2 * currentForwardSpeed * m_dragModifier;

	m_body->ApplyForce(m_currentTraction * dragForceMagnitude * currentForwardNormal, m_body->GetWorldCenter(), true);
}