Function DoTriggerHouseRandomisation

src/newgrf_house.cpp:662–709

}

static void DoTriggerHouseRandomisation(TileIndex tile, HouseRandomTrigger trigger, uint8_t base_random, bool first)
{
	/* We can't trigger a non-existent building... */
	assert(IsTileType(tile, MP_HOUSE));

	HouseID hid = GetHouseType(tile);
	HouseSpec *hs = HouseSpec::Get(hid);

	if (!hs->grf_prop.HasSpriteGroups()) return;

	HouseResolverObject object(hid, tile, Town::GetByTile(tile), CBID_RANDOM_TRIGGER);
	auto waiting_random_triggers = GetHouseRandomTriggers(tile);
	waiting_random_triggers.Set(trigger);
	SetHouseRandomTriggers(tile, waiting_random_triggers); // store now for var 5F
	object.SetWaitingRandomTriggers(waiting_random_triggers);

	object.ResolveRerandomisation();

	/* Store remaining triggers. */
	waiting_random_triggers.Reset(object.GetUsedRandomTriggers());
	SetHouseRandomTriggers(tile, waiting_random_triggers);

	/* Rerandomise bits. Scopes other than SELF are invalid for houses. For bug-to-bug-compatibility with TTDP we ignore the scope. */
	uint8_t new_random_bits = Random();
	uint8_t random_bits = GetHouseRandomBits(tile);
	uint32_t reseed = object.GetReseedSum();
	random_bits &= ~reseed;
	random_bits |= (first ? new_random_bits : base_random) & reseed;
	SetHouseRandomBits(tile, random_bits);

	switch (trigger) {
		case HouseRandomTrigger::TileLoop:
			/* Random value already set. */
			break;

		case HouseRandomTrigger::TileLoopNorth:
			if (!first) {
				/* The top tile is marked dirty by the usual TileLoop */
				MarkTileDirtyByTile(tile);
				break;
			}
			/* Random value of first tile already set. */
			if (hs->building_flags.Any(BUILDING_2_TILES_Y))   DoTriggerHouseRandomisation(TileAddXY(tile, 0, 1), trigger, random_bits, false);
			if (hs->building_flags.Any(BUILDING_2_TILES_X))   DoTriggerHouseRandomisation(TileAddXY(tile, 1, 0), trigger, random_bits, false);
			if (hs->building_flags.Any(BUILDING_HAS_4_TILES)) DoTriggerHouseRandomisation(TileAddXY(tile, 1, 1), trigger, random_bits, false);
			break;
	}
}

void TriggerHouseRandomisation(TileIndex t, HouseRandomTrigger trigger)
{