This means that an early return or an exception between
a manual Push/Pop (or an omission of the Pop) cannot
corrupt the layer stack.
It also means the GAL doesn't have to maintain its own
stack (with the in-scope GAL_SCOPED_ATTRS taking that role).
Reomve the Push/PopDepth functions, as they're only ever
used in pairs, and doing it manually needs more care.
Some shapes, like arcs and beziers have "lines" that
can be useful to see when editing, but aren't directly
editable and may not overlap the object's own lines.
So make it possible to, indepedently:
- Turn off the centre-point drag handle affordance
- Show the actual line segment on screen.
* Split up the thirdparty code into the thirdparty folder (#3637)
* Create a new kimath static library containing all the math functions
This is part of cleaning the build system for #1906.
This also finishes the polygon with 45° lines when chosen as a create
option.
Fixes: lp:1833673
* https://bugs.launchpad.net/kicad/+bug/1833673
(cherry picked from commit fccce265aa959f5f234d32dcd29e01c1f25bd9a5)
