There was a gentle mish-mash of booleans, some with
true being left/right and some up/down, and some functions that
can flip in both axes (which is never actually done, and doesn't
really make geometric sense).
Replace all this with the FLIP_DIRECTION enum class, which makes
the intention completely unambiguous.
This also then allows a small scattering of simplifications,
because everything takes the same type and you don't have to
fiddle booleans to fit.
ADDED: Add support in Pcbnew for exporting ODB++ files under Fabrication
Outputs, base on ODB++Design Format Specification (Release v8.1
Update 3 February 2021).
Note: There is still a lot of work to do if we will make the feature as
complete as the ODB++ spec. However, the current functionality's
completeness is already sufficient to cover general production
scenarios. I have compared the output results with Gerber files by
DFM tool and the accuracy at the graphic level should be able to
cover most usage scenarios. Additionally, I am very grateful to
the great open-source project Horizon EDA for giving me a lot of
inspiration in terms of ideas.
The feature can be enabled by adding "EnableODB=1" to the kicad_advanced
configuration file.
Fixes https://gitlab.com/kicad/code/kicad/-/issues/2019
