Update xatlas to latest upstream commit (b7d7bb9).

[fire]

Update xatlas to 1681e63

[fire]

Needs testing, not sure if we require the per triangle code.

[fire]

Reminder to remove patch files when close to done.

[fire]

This is confusing.

thirdparty\xatlas\xatlas.cpp(2338): note: see reference to class template instantiation 'xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>::D' being compiled
thirdparty\xatlas\xatlas.cpp(2331): note: while compiling class template member function 'bool xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>::ref(uint32_t) const'
thirdparty\xatlas\xatlas.cpp(2470): note: see reference to function template instantiation 'bool xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>::ref(uint32_t) const' being compiled
thirdparty\xatlas\xatlas.cpp(2673): note: see reference to class template instantiation 'xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>' being compiled
thirdparty\xatlas\xatlas.cpp(2379): error C2065: 'state': undeclared identifier
thirdparty\xatlas\xatlas.cpp(2379): error C2327: 'xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>::D::version': is not a type name, static, or enumerator
thirdparty\xatlas\xatlas.cpp(2379): error C2065: 'version': undeclared identifier
thirdparty\xatlas\xatlas.cpp(2379): error C2327: 'xatlas::internal::task::ObjectPool<xatlas::internal::task::Scheduler::Counter>::D::element': is not a type name, static, or enumerator
thirdparty\xatlas\xatlas.cpp(2379): error C2065: 'element': undeclared identifier
scons: *** [thirdparty\xatlas\xatlas.windows.opt.tools.64.obj] Error 2
scons: building terminated because of errors.

[fire]

What that means is that msvc 2017 is required and msvc 2015 isn't supported?

[akien-mga]

I'd prefer that we keep supporting MSVC 2015 for the time being, even though using 2017 or later is definitely recommended.

[jpcy]

xatlas::MeshDecl data fields don't need to be allocated, you could assign them to p_indices, p_vertices etc. directly instead.

[fire]

@jpcy Can you see why the system is limited to one core?

[jpcy]

Multithreaded tasks aren't very finely grained at this point. A single mesh where all faces are connected will only use one core. I should be able to improve that soon, but I need to swap out the current task scheduler with one that can create sub tasks from any thread first.

[fire]

Will test jpcy/xatlas@b7d7bb9 for performance changes.

[JFonS]

LGTM

[fire]

Regarding performance improvements, there are still changes in jpcy/xatlas#22 and the repository.

However, at this very moment, there is no difference in performance between the master and this pull request. Both are still single core locked. So we should be ok to merge and when xatlas has the performance improvement, we can pull request again.

[akien-mga]

Sounds good to me, let's merge :)

[akien-mga]

Thanks!