Introduce a new header `gil.h` defining `MutexLockIfGilDisabled` to support thread-safety in both standard and free-threaded CPython builds.
Protect critical shared states and registries:
- Guard global Python callback pointers in `callbacks.cc` using a mutex. Move `gil_scoped_acquire` into local blocks around refcount modifications to prevent `longjmp` from bypassing destructors.
- Protect raw pointer maps in `structs_wrappers.cc` with static mutexes.
- Replace TOCTOU race in `mjcb_time` initialization with thread-safe `std::call_once`.
- Add synchronization to lazy indexer array cache initialization in `indexers.cc` and `indexer_xmacro.h`.
- Protect vector mutations in `StructListBase::PopulateUpTo` in `structs.h` with a mutex.
- Revert unnecessary atomic changes to threadpool counters.
- Declare free-threading compatibility by passing `pybind11::mod_gil_not_used()` to all extension modules.
Fixes#3259Fixes#3256Fixes#2978
PiperOrigin-RevId: 941101502
Change-Id: Iec4ce58afcbc75d4b0be6a9a21fc8a47854242e3
This change adds py::gil_scoped_release to various functions in the parser, renderer, sim and ux modules of the MuJoCo Studio Python bindings. This allows other Python threads to execute while these C++ functions, which can sometimes be time-consuming, are running. The two heaviest operations Present() (rendering) and Advance() (physics) now both release the GIL in C++.
PiperOrigin-RevId: 930645361
Change-Id: Ib239fb54edc7ac0d8b1d94bec8c57a447d5f4d27
Following the export declarations in Dear ImGui and ImPlot METADATA, this change updates MuJoCo's Copybara configuration (copy.bara.sky) to export and transform the Python bindings. `//third_party/dear_imgui/google/py` exports to `python/mujoco/experimental/dear_imgui` and `//third_party/implot/google/py` exports to `python/mujoco/experimental/implot`.
PiperOrigin-RevId: 925293624
Change-Id: Ie6e32d247a6f7fc24bb36ae7060f2075d8efeb26
Saran Tunyasuvunakool