Method GetCurrentMaxSpeed

src/train_cmd.cpp:382–427

* Calculates the maximum speed of the vehicle under its current conditions. * @return Maximum speed of the vehicle. */

 * @return Maximum speed of the vehicle.
 */
int Train::GetCurrentMaxSpeed() const
{
	int max_speed = _settings_game.vehicle.train_acceleration_model == AM_ORIGINAL ?
			this->gcache.cached_max_track_speed :
			this->tcache.cached_max_curve_speed;

	if (_settings_game.vehicle.train_acceleration_model == AM_REALISTIC && IsRailStationTile(this->tile)) {
		StationID sid = GetStationIndex(this->tile);
		if (this->current_order.ShouldStopAtStation(this, sid)) {
			int station_ahead;
			int station_length;
			int stop_at = GetTrainStopLocation(sid, this->tile, this, &station_ahead, &station_length);

			/* The distance to go is whatever is still ahead of the train minus the
			 * distance from the train's stop location to the end of the platform */
			int distance_to_go = station_ahead / TILE_SIZE - (station_length - stop_at) / TILE_SIZE;

			if (distance_to_go > 0) {
				int st_max_speed = 120;

				int delta_v = this->cur_speed / (distance_to_go + 1);
				if (max_speed > (this->cur_speed - delta_v)) {
					st_max_speed = this->cur_speed - (delta_v / 10);
				}

				st_max_speed = std::max(st_max_speed, 25 * distance_to_go);
				max_speed = std::min(max_speed, st_max_speed);
			}
		}
	}

	for (const Train *u = this; u != nullptr; u = u->Next()) {
		if (_settings_game.vehicle.train_acceleration_model == AM_REALISTIC && u->track == TRACK_BIT_DEPOT) {
			max_speed = std::min(max_speed, 61);
			break;
		}

		/* Vehicle is on the middle part of a bridge. */
		if (u->track == TRACK_BIT_WORMHOLE && !u->vehstatus.Test(VehState::Hidden)) {
			max_speed = std::min<int>(max_speed, GetBridgeSpec(GetBridgeType(u->tile))->speed);
		}
	}

	max_speed = std::min<int>(max_speed, this->current_order.GetMaxSpeed());
	return std::min<int>(max_speed, this->gcache.cached_max_track_speed);
}

/** Update acceleration of the train from the cached power and weight. */
void Train::UpdateAcceleration()