Method UpdateSpeed

src/roadveh_cmd.cpp:739–749

* This function looks at the vehicle and updates its speed (cur_speed * and subspeed) variables. Furthermore, it returns the distance that * the vehicle can drive this tick. #Vehicle::GetAdvanceDistance() determines * the distance to drive before moving a step on the map. * @return distance to drive. */

 * @return distance to drive.
 */
int RoadVehicle::UpdateSpeed()
{
	switch (_settings_game.vehicle.roadveh_acceleration_model) {
		default: NOT_REACHED();
		case AM_ORIGINAL:
			return this->DoUpdateSpeed(this->overtaking != 0 ? 512 : 256, 0, this->GetCurrentMaxSpeed());

		case AM_REALISTIC:
			return this->DoUpdateSpeed(this->GetAcceleration() + (this->overtaking != 0 ? 256 : 0), this->GetAccelerationStatus() == AS_BRAKE ? 0 : 4, this->GetCurrentMaxSpeed());
	}
}

static Direction RoadVehGetNewDirection(const RoadVehicle *v, int x, int y)
{