The issue is with "dllexport": previously, dllexport was present on
exposed templates tool (= visibility(default) for gcc/clang). This
ensured MacOS compatibility since then the typeinfo is corretly
shared and dynamic_cast/typeid works.
For Windows, the "dllexport" equivalent requires the template
instantiations to be declared "external" which is a coding nightmare.
The solution is to provide separate macros for real (non-specialized,
not explicitly instantiated) templates (.._PUBLIC_TEMPLATE) which
is defined as empty for Windows and "visiblity(default)" for gcc/clang.
1.) Startup issue:
This is solved by making sure templates with virtual functions
are made visible in the DSO. This way, dynamic_cast is possible
across DSO's.
Scary: clang/MacOS wants the forward declarations be declared visible as well.
2.) Menu issue:
The best solution is to have only one QMenuBar. The navigator
now gets a synthetic menu bar composed of QToolButtons.
This solution will not only fix this issue but also turn
pairs of edges into "edge pair" objects. These objects
provide a somewhat better visualization for DRC violations
by connecting the edges with a filled region.
Single edges and clusters of more than two edges are
represented as individual edges.