Use SetPoint instead of InsertPoint() when number of points is known.
Replaced InsertNextXXX() with SetXXX() where possible.

Added some more VtkPolyData::Squeeze()-calls.
Maybe VtkStationSource and VtkConditionSource can be optimized further.
find intersections of polylines and mesh element edges
fixed to issues introduced with optimisation
restructured point duplication and added line duplication
extracted line duplication to seperate function
new points are now added to lines
new geo name is given as parameter
implemented updating of polyline node indices + real data modifications
fixed a sign-error and optimised the code
removed elevation calculation as this will be applied laterfor all nodes via collision detection
merge changes
linked functionality to GUI
added comments
added support for quad-elements, added error-msg if mesh is not 2D
added dialog error msg
moved eps calculation to AABB
removed testing functionality
Fixed missing include and a typo.
added fixed based on PR comments