There are several ExPolygons with very thin lines and holes formed by very close (1-5nm) vertices that are on the edge of our resolution. Those thin lines and holes are both unprintable and cause the Voronoi diagram to be invalid.
So, we filtered out such thin lines and holes and tried to compute the Voronoi diagram again.
Ignore the first intersection of the travel path with the object from which the travel starts.
Created a new class TravelObstacleTracker, for wrapping all data structures related to lift before obstacles.
During layer change, instead of generating the gcode, generate a placeholder tag. Then at the end of layer processing replace this tag with a ramping travel move.
This solves the issue, that one does not know the starting point of the current layer where the layer change gcode would be originally generate.
The ramping layer changes uses smoothing of the ramping travel. Also it is adjusted in such a way that it increases the ramp angle when the travel is too short, to always reach the next layer.
Split Integrals constructor to accept polygon and polygons.
Add operator+(Integrals, Integrals).
Make sure extrusion extraction for integral calculation throws in invalid case.
In SupportSpotsGenerator there is a need to compute integral over
extrusions.
The mentioned function is slow for this use case. As it solves a harder
problem.
It is better to iterate the extrusion lines directly.
A line distancer over previous layer is constructed. It is then queried
during travel planing. If an obstacle is found in the travel path,
the travel algorithm ensures minimal elevation before the obstacle.
The new travel has an initial flat part, sloped part and
once the travel height reaches maxima a flat part again.
Also, the notion of extruder lift is removed. It is used no more.
Consequently the retract_lift parameter lost its original meaning.
There was a test that relied on randomness and also checked the result
with very hight precision. That led to a failed test once upon a time.
Now the checking is more benevolent (it should be, as the code is
not expected to be precise) and also the randomness is removed.
