Function PhysicsApplyConstRotForce

physics/physics.cpp:229–255

Applies rotational thrust over at delta time

// Applies rotational thrust over at delta time
void PhysicsApplyConstRotForce(object &objp, const vector &rotforce, vector &rotvel, float deltaTime) {
  const double drag = objp.mtype.phys_info.rotdrag;
  const double mass = objp.mtype.phys_info.mass;

  if (mass < std::numeric_limits<double>::epsilon() || drag < std::numeric_limits<double>::epsilon()) {
    // Invalid mass/drag
    rotvel += rotforce * deltaTime;
    return;
  }

  // Standard angular motion with a linear air drag (drag is proportional to angular velocity)
  const double oneOverDrag = 1.0 / drag;
  const double rotForceOverDrag[3] = {double(rotforce.x) * oneOverDrag, double(rotforce.y) * oneOverDrag,
                                      double(rotforce.z) * oneOverDrag};
  const double dragOverMass = drag / mass;
  const double expDoMDt = exp(-dragOverMass * double(deltaTime));

  double newRotVel[3];
  newRotVel[0] = (double(rotvel.x) - rotForceOverDrag[0]) * expDoMDt + rotForceOverDrag[0];
  newRotVel[1] = (double(rotvel.y) - rotForceOverDrag[1]) * expDoMDt + rotForceOverDrag[1];
  newRotVel[2] = (double(rotvel.z) - rotForceOverDrag[2]) * expDoMDt + rotForceOverDrag[2];

  // set the new rotational velocity
  rotvel.x = static_cast<float>(newRotVel[0]);
  rotvel.y = static_cast<float>(newRotVel[1]);
  rotvel.z = static_cast<float>(newRotVel[2]);
}

// Applies a linear force over time.  --Like gravity or thrust
void PhysicsApplyConstantForce(const object &objp, vector &newPos, vector &newVel, vector &movementVec,