## Summary of Changes
The changes fix a bug in the extensions of vertex and halfedge types of
the DCEL when used to instantiate Arrangement_with_history_2 or similar
arrangement classes that derive from Arrangement_2.
Typically, only the face type is extended or all the 3 types (vertex,
halfedge, and face) are extended, and for such extensions we have
dedicated class templates. The bug shows up when trying to extend any
other subset of the 3 types, and apparently, this hasn't been used much
with Arrangement_with_history_2.
## Release Management
* Affected package(s): Arrangement_on_surface_2
* Issue(s) solved (if any): NA
* Feature/Small Feature (if any): NA
* Link to compiled documentation: NA
* License and copyright ownership: TAU
## Fixed the Landmark point-location strategy of the Aos_2 package, so
that it can be applied to arrangements on a sphere.
The title says it all.
I slightly changed one paragraph in the user manual.
Here is the new version:
The arrangement attached to the landmark strategy must be either (i) an
instance of the `Arrangement_2]<Geom,Dcel>` class template, where the
`Traits` parameter is substituted by a geometry-traits class that models
the `ArrangementLandmarkTraits_2` concept, or (ii) an instance of the
`Arrangement_on_surface_2<GeomTraits,TopolTraits>` class template, where
the `GeometryTraits` is similarly substituted; see Section The Landmark
Concept for details about this concept.
## Release Management
* Affected package(s): Arrangement_on_surface_2
* Issue(s) solved (if any): NA
* Feature/Small Feature (if any): NA
* Link to compiled documentation: Changed one paragraph; see above.
* License and copyright ownership: TAU
Fixed the code that computes intersections in the polycurve traits
(Arr_polycurve_traits_2).
## Summary of Changes
The code of the Intersection_2 functor was developed from scratch.
The old code only supported polylines (by mistake), that is, chains of
segments.
The new code supports intersections of chains of any type of sub-curves.
It turns out that the new code is ~15% more efficient.
While at it, I replaced 'typedef' statements with modern 'using'
statements.
## Release Management
Apparently, there is no "CHANGES.md" file yet for 6.1, so I'll add an
entry that informs about this fix after it is introduced (to 'master'
and 'master' is merged to this branch.)
* Affected package(s): Arrangement_on_surface_2
* Issue(s) solved (if any): fix#8468
* Feature/Small Feature (if any):
* Link to compiled documentation (obligatory for small feature) [*wrong
link name to be changed*](httpssss://wrong_URL_to_be_changed/Manual/Pkg)
* License and copyright ownership: TAU
Guillaume Damiand
Sébastien Loriot
Mael Rouxel-Labbé
Efi Fogel
albert-github
Sebastien Loriot
Sven Oesau
Andreas Fabri