3. Main Section: Building Bottoms (optional)

Buildings defined using the section explained above all start at ground surface (z=0) as houses normally do.
If you want to define buildings beginning at a different height, an additional Building Bottom Section is needed.
Click here to see an example section.

This section begins with the keyword \BOTTOM followed by a structure similar to the main section shown before.
Again, the height to building bottom is given in meters. Bottom information without a building on the grid or bottoms higher than the roof level of the associated building are ignored. The vertical grid resolution limits the possibilities of defining overhanging structures.

If you don't need non-zero bottoms, the \BOTTOM keyword must be replaced with a single remark line “%….”.