Function TryBuildLightHouse

src/object_cmd.cpp:750–789

* Try to build a lighthouse. * @return True iff building a lighthouse succeeded. */

 * @return True iff building a lighthouse succeeded.
 */
static bool TryBuildLightHouse()
{
	uint maxx = Map::MaxX();
	uint maxy = Map::MaxY();
	uint r = Random();

	/* Scatter the lighthouses more evenly around the perimeter */
	int perimeter = (GB(r, 16, 16) % (2 * (maxx + maxy))) - maxy;
	DiagDirection dir;
	for (dir = DIAGDIR_NE; perimeter > 0; dir++) {
		perimeter -= (DiagDirToAxis(dir) == AXIS_X) ? maxx : maxy;
	}

	TileIndex tile;
	switch (dir) {
		default:
		case DIAGDIR_NE: tile = TileXY(maxx - 1, r % maxy); break;
		case DIAGDIR_SE: tile = TileXY(r % maxx, 1); break;
		case DIAGDIR_SW: tile = TileXY(1,        r % maxy); break;
		case DIAGDIR_NW: tile = TileXY(r % maxx, maxy - 1); break;
	}

	/* Only build lighthouses at tiles where the border is sea. */
	if (!IsTileType(tile, MP_WATER) || GetWaterClass(tile) != WaterClass::Sea) return false;

	for (int j = 0; j < 19; j++) {
		int h;
		if (IsTileType(tile, MP_CLEAR) && IsTileFlat(tile, &h) && h <= 2 && !IsBridgeAbove(tile)) {
			for (auto t : SpiralTileSequence(tile, 9)) {
				if (IsObjectTypeTile(t, OBJECT_LIGHTHOUSE)) return false;
			}
			BuildObject(OBJECT_LIGHTHOUSE, tile);
			assert(tile < Map::Size());
			return true;
		}
		tile += TileOffsByDiagDir(dir);
		if (!IsValidTile(tile)) return false;
	}
	return false;
}

/**
 * Try to build a transmitter.