Function CanPlantTreesOnTile

src/tree_cmd.cpp:59–71

* Tests if a tile can be converted to MP_TREES * This is true for clear ground without farms or rocks. * * @param tile the tile of interest * @param allow_desert Allow planting trees on CLEAR_DESERT? * @return true if trees can be built. */

 * @return true if trees can be built.
 */
static bool CanPlantTreesOnTile(TileIndex tile, bool allow_desert)
{
	switch (GetTileType(tile)) {
		case MP_WATER:
			return !IsBridgeAbove(tile) && IsCoast(tile) && !IsSlopeWithOneCornerRaised(GetTileSlope(tile));

		case MP_CLEAR:
			return !IsBridgeAbove(tile) && !IsClearGround(tile, CLEAR_FIELDS) && !IsClearGround(tile, CLEAR_ROCKS) &&
			       (allow_desert || !IsClearGround(tile, CLEAR_DESERT));

		default: return false;
	}
}

/**
 * Creates a tree tile