void Wander::getSteering(SteeringOutput* output)
{
// Make sure we have a target
if (target->squareMagnitude() == 0) {
internal_target = character->position;
internal_target.x += volatility;
}
Vector3 offset = *target - character->position;
real angle;
if (offset.x*offset.x + offset.z*offset.z > 0) {
// Work out the angle to the target from the character
angle = real_atan2(offset.z, offset.x);
}
else
{
// We're on top of the target, move it away a little.
angle = 0;
}
// Move the target to the boundary of the volatility circle.
internal_target = character->position;
internal_target.x += volatility * real_cos(angle);
internal_target.z += volatility * real_sin(angle);
// Add the turn to the target
internal_target.x += randomBinomial(turnSpeed);
internal_target.z += randomBinomial(turnSpeed);
Seek::getSteering(output);
}
void game_physics_engine::CParticalFakeSpring::UpdateForce( CPartical* pPartical, const real duration )
{
if (!pPartical->HasFiniteMass())
{
return;
}
CVector3 position = pPartical->GetPosition();
position -= *m_pAnchor;
real gamma = 0.5f * (real_sqrt(4 * m_fSpringConstant - m_fDamping * m_fDamping));
CVector3 c = position * (m_fDamping / (2 * gamma)) + pPartical->GetVelocity() * (1.0f / gamma);
CVector3 target = position * real_cos(gamma * duration) + c * real_sin(gamma * duration);
target *= real_exp(-0.5f * duration * m_fDamping);
CVector3 accel = (target - position) * (1.0f / duration * duration) - pPartical->GetVelocity() * duration;
pPartical->AddForce(accel * pPartical->GetMass());
}
Vector3 Location::getOrientationAsVector() const
{
return Vector3(real_sin(orientation),
0,
real_cos(orientation));
}
