Function RoadVehUpdateCache

src/roadveh_cmd.cpp:219–252

* Update the cache of a road vehicle. * @param v Road vehicle needing an update of its cache. * @param same_length should length of vehicles stay the same? * @pre \a v must be first road vehicle. */

 * @pre \a v must be first road vehicle.
 */
void RoadVehUpdateCache(RoadVehicle *v, bool same_length)
{
	assert(v->type == VEH_ROAD);
	assert(v->IsFrontEngine());

	v->InvalidateNewGRFCacheOfChain();

	v->gcache.cached_total_length = 0;

	for (RoadVehicle *u = v; u != nullptr; u = u->Next()) {
		/* Check the v->first cache. */
		assert(u->First() == v);

		/* Update the 'first engine' */
		u->gcache.first_engine = (v == u) ? EngineID::Invalid() : v->engine_type;

		/* Update the length of the vehicle. */
		uint veh_len = GetRoadVehLength(u);
		/* Verify length hasn't changed. */
		if (same_length && veh_len != u->gcache.cached_veh_length) VehicleLengthChanged(u);

		u->gcache.cached_veh_length = veh_len;
		v->gcache.cached_total_length += u->gcache.cached_veh_length;

		/* Update visual effect */
		u->UpdateVisualEffect();

		/* Update cargo aging period. */
		u->vcache.cached_cargo_age_period = GetVehicleProperty(u, PROP_ROADVEH_CARGO_AGE_PERIOD, EngInfo(u->engine_type)->cargo_age_period);
	}

	uint max_speed = GetVehicleProperty(v, PROP_ROADVEH_SPEED, 0);
	v->vcache.cached_max_speed = (max_speed != 0) ? max_speed * 4 : RoadVehInfo(v->engine_type)->max_speed;
}

/**
 * Build a road vehicle.