Function AlignTileToGrid

src/town_cmd.cpp:2298–2305

* Towns must all be placed on the same grid or when they eventually * interpenetrate their road networks will not mesh nicely; this * function adjusts a tile so that it aligns properly. * * @param tile The tile to start at. * @param layout The town layout in effect. * @return The adjusted tile. */

 * @return The adjusted tile.
 */
static TileIndex AlignTileToGrid(TileIndex tile, TownLayout layout)
{
	switch (layout) {
		case TL_2X2_GRID: return TileXY(TileX(tile) - TileX(tile) % 3, TileY(tile) - TileY(tile) % 3);
		case TL_3X3_GRID: return TileXY(TileX(tile) & ~3, TileY(tile) & ~3);
		default:          return tile;
	}
}

/**
 * Towns must all be placed on the same grid or when they eventually