For unknown reasons, Clipper2 only returns Paths structures from the
ClipperOffset::Execute routine. Further, the Paths are not properly
ordered (outline->hole in outline, outline2->hole in outline2).
To get proper hierarchy, we need to run an additional pass of the
solution with the paths as Subject in a null union. This is effectively
a Simplify() call but we keep the data in Clipper format to reduce the
churn/calc time
Some clipper cases do not get resolved with the `FAST` mode, so in those
cases, do a second pass in the `SIMPLE` mode. If both fail, return a
broken polygon instead of an infinite loop
Fixes https://gitlab.com/kicad/code/kicad/issues/12761
In Clipper1, we had a flat tree structure on returns. Clipper2 nests
these, so we need to properly handle the nesting structure when
importing the polygons
Currently this lives behind the advanced config flag `UseClipper2`.
Enabling this flag will route all Clipper-based calls through the
Clipper2 library instead of the older Clipper. The changes should be
mostly transparent.
Of note, Clipper2 does not utilize the `STRICTLY_SIMPLE` flag because
clipper1 did not actually guarantee a strictly simple polygon.
Currently we ignore this flag but we may decide to run strictly-simple
operations through a second NULL union to simplify the results as much
as possible.
Additionally, the inflation options are slightly different. We cannot
choose the fallback miter. The fallback miter is always square. This
only affects the CHAMFER_ACUTE_CORNERS option in inflate, which does not
appear to be used.
Lastly, we currently utilize the 64-bit integer coordinates for
calculations. This appears to still be faster than 32-bit calculations
in Clipper1 on a modern x86 system. This may not be the case for older
systems, particularly 32-bit systems.
In addition to showing resolved clearance, we also show the calculated
clearance in the same method as is used for DRC. This will allow users
to better examine their system while working.
Fixes https://gitlab.com/kicad/code/kicad/issues/7934
We can't know that all holes will be ccw when entering unfracture.
Instead, we set the largest polyline to be the outline and the others to
be the holes.
(cherry picked from commit 1fe956c06961ad7e1364f8e9ea6d6c55218570e1)
Inflate with linked holes needs to account for fractured polygons,
otherwise inflating with positive value will create rounded divots where
overlapping fracture lines meet and inflating with negative value will
create spaces between fracture lines.
Calling Simplify before Inflate takes an inordinate amount of time as
the Clipper healing routine is rather slow. Our own Unfracture is meant
to heal the results of our Fracture routine and works much more quickly.
After healing, we still call the Simplify routine
(cherry picked from commit 9ca35cbcee47ec844d491b4d4a9047b518e8aced)
Clipper can handle complex input polygons but we will sometimes struggle
dealing with outputs from the inflate routine that have degenerate or
overlapping points. Calling Simplify after the inflate keeps our
polygons easier to handle
Fixes https://gitlab.com/kicad/code/kicad/issues/11036
(cherry picked from commit a24cdcb3f0f22c7b0a24fc452658f1dcb57c9870)
1) Generate SHAPE_POLY_SET triangulation by outline so they can be
shared between connectivity system and other clients.
2) Don't add items to connectivity when reading board; we're going
to do a total rebuild anyway.
3) Use multithreading when caching triangulation.
Boolean Ops on polygons with arcs are not supported (the only exception
is Simplify)
Also fix a bug in SHAPE_LINE_CHAIN::splitArc that resulted in an
exception
Partially fixes https://gitlab.com/kicad/code/kicad/-/issues/9380
If the last three points of a tesselation are concave, we will never be
able to triangulate them. They were likely formed from a bad polygon,
so we will drop the triangle and return completed
Fixes https://gitlab.com/kicad/code/kicad/issues/9380
We are not always sure of the path validity in fracture. Nominally, the
Clipper Simplify routine should remove invalid parts but in the case
where it doesn't, we need to recover gracefully, even if the output
polygon is not valid.
Fixes https://gitlab.com/kicad/code/kicad/issues/9199
It appears as though there was an optimization to skip testing segments if
one of their endpoints (and only the A point) was inside. Unclear the reason
for this, but I'm going to assume that it was intended to optimize the case
where both points are inside (like the point case above it).
