IO: write_PLY() for Epeck

[afabri]

Summary of Changes

As reported in #7868 the function CGAL::IO::write_PLY() used in binary mode does not correctly write the coordinates if the points are from a kernel with exact constructions.
This PR applies `to_double()" to the coordinates.

After a discussion with @MaelRL we decided that the user is in charge to pass a vertex_point_map as named parameter that does the conversion. This is straightforward as we offer the Cartesian_converter_property_map.

Moving back to the previous proposal: hardcode some to_double and to_float casts such that we meet the requirements of the file format, whatever the input.

As the problem is the same for the vertex normals we add a named parameter vertex_normal_map.

Todo

• Fix the generic function write_polygon_mesh(). Currently it is fixed for Surface_mesh

Release Management

• Affected package(s): Stream_support
• Issue(s) solved (if any): fix invalid result from CGAL::IO::write_PLY() #7868 and fix Writing a binary PLY file does not work with an EPECK mesh #7327
• License and copyright ownership: unchanged
• upcoming integration, update Stream support: Fix for Epeck #9072 and test it

[sloriot]

BGL tests failing in CGAL-6.0-Ic-112

[sloriot]

Successfully tested in CGAL-6.0-Ic-116

[lrineau]

@afabri There is still an undone TODO in the top message of this other PR. Do you want this PR merged as it is?

[afabri]

@afabri There is still an undone TODO in the top message of this other PR. Do you want this PR merged as it is?

No, I still want to fix the generic code.

[sloriot]

@afabri any chance you can fix that today (if inclusion in 5.6.1 is needed)?

[sloriot]

@afabri, this PR was marked tested 2 month ago and is still waiting for a TODO. Maybe you want to open an issue instead and integrate the PR.

[lrineau]

Ping @afabri

[afabri]

Ping @afabri

Will be treated somewhere in the future.

[github-actions]

The documentation is built. It will be available, after a few minutes, here: https://cgal.github.io/7874/v0/Manual/index.html

[afabri]

/force-build:v0

[github-actions]

The documentation is built. It will be available, after a few minutes, here: https://cgal.github.io/7874/v0/Manual/index.html

[sloriot]

@afabri please resolve all conversations

[sloriot]

Successfully tested in CGAL-6.2-Ic-39