Version 2.1.1: Binaries for ARM64, proper macOS bundles, minor bugfixes.

Closes #2
Closes #42
Closes #59

PiperOrigin-RevId: 416794598
Change-Id: I1306df1127d6acecf2323873c0da0910f35d31a0

doc/changelog.rst

@@ -1,12 +1,111 @@
-.. include:: includes/macros.rst
-.. include:: includes/roles.rst
-
 =========
 Changelog
 =========
 
-Version 2.1 (Oct. 18, 2021)
----------------------------
+Version 2.1.1 (Dec. 16, 2021)
+-----------------------------
+
+API changes
+^^^^^^^^^^^
+
+1. Added ``mj_printFormattedModel``, which accepts a format string for floating point numbers, for example to increase
+   precision.
+#. Added ``mj_versionString``, which returns human-readable string that represents the version of the MuJoCo binary.
+#. Converted leading underscores to trailing underscores in private instances of API struct definitions, to conform to
+   reserved identifier directive, see
+   `C standard: Section 7.1.3 <www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf>`__.
+
+   .. attention::
+      This is a minor breaking change. Code which references private instances will break. To fix, replace leading
+      underscores with trailing underscores, e.g. ``_mjModel`` |rarr| ``mjModel_``.
+
+General
+^^^^^^^
+
+4. Safer string handling: replaced ``strcat``, ``strcpy``, and ``sprintf`` with ``strncat``, ``strncpy``, and
+   ``snprintf`` respectively.
+#. Changed indentation from 4 spaces to 2 spaces everywhere.
+
+Bug Fixes
+^^^^^^^^^
+
+6. Fixed reading from uninitialized memory in PGS solver.
+#. Computed capsule inertias are now exact. Until this change, capsule masses and inertias computed by the
+   :ref:`compiler <compiler>`'s :at:`inertiafromgeom` mechanism were approximated by a cylinder, formed by the
+   capsule's cylindrical middle section, extended on both ends by half the capsule radius. Capsule inertias are now
+   computed with the `Parallel Axis theorem <https://en.wikipedia.org/wiki/Parallel_axis_theorem>`_, applied to the two
+   hemispherical end-caps.
+
+   .. attention::
+      This is a minor breaking change. Simulation of a model with automatically-computed capsule inertias will be
+      numerically different, leading to, for example, breakage of golden-value tests.
+#. Fixed bug related to :ref:`force <sensor-force>` and :ref:`torque <sensor-torque>` sensors. Until this change, forces
+   torques reported by F/T sensors ignored out-of-tree constraint wrenches except those produced by contacts. Force and
+   and torque sensors now correctly take into account the effects of :ref:`connect <equality-connect>` and
+   :ref:`weld <equality-weld>` constraints.
+
+   .. note::
+      Forces generated by :ref:`spatial tendons <spatial>` which are outside the kinematic tree (i.e. between bodies
+      which have no ancestral relationship) are still not taken into account by force and torque sensors. This remains a
+      future work item.
+
+Code samples
+^^^^^^^^^^^^
+
+9. ``testspeed``: Added injection of pseudo-random control noise, turned on by default. This is to avoid settling into
+   some fixed contact configuration and providing an unrealistic timing measure.
+#. ``simulate``:
+
+   a. Added slower-than-real-time functionality, which is controlled via the '+' and '-' keys.
+   #. Added sliders for injecting Brownian noise into the controls.
+   #. Added "Print Camera" button to print an MJCF clause with the pose of the current camera.
+   #. The camera pose is not reset when reloading the same model file.
+
+Updated dependencies
+^^^^^^^^^^^^^^^^^^^^
+
+11. ``TinyXML`` was replaced with ``TinyXML2`` 6.2.0.
+#. ``qhull`` was upgraded to version 8.0.2.
+#. ``libCCD`` was upgraded to version 1.4.
+#. On Linux, ``libstdc++`` was replaced with ``libc++``.
+
+Binary build
+^^^^^^^^^^^^
+
+15. MacOS packaging. We now ship Universal binaries that natively support both Apple Silicon and Intel CPUs.
+
+    a. MuJoCo library is now packaged as a
+       `Framework Bundle <https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/FrameworkAnatomy.html>`_,
+       allowing it to be incorporated more easily into Xcode projects (including Swift projects). Developers are
+       encouraged to compile and link against MuJoCo using the ``-framework mujoco`` flag, however all header files and
+       the ``libmujoco.2.1.1.dylib`` library can still be directly accessed inside the framework.
+    #. Sample applications are now packaged into an Application Bundle called ``MuJoCo.app``. When launched via GUI,
+       the bundle launches the ``simulate`` executable. Other precompiled sample programs are shipped inside that bundle
+       (in ``MuJoCo.app/Contents/MacOS``) and can be launched via command line.
+    #. Binaries are now signed and the disk image is notarized.
+
+#. Windows binaries and libraries are now signed.
+#. Link-time optimization is enabled on Linux and macOS, leading to an average of \~20% speedup when benchmarked on
+   three test models (``cloth.xml``, ``humanoid.xml``, and ``humanoid100.xml``).
+#. Linux binaries are now built with LLVM/Clang instead of GCC.
+#. An AArch64 (aka ARM64) Linux build is also provided.
+#. Private symbols are no longer stripped from shared libraries on Linux and MacOS.
+
+Sample models
+^^^^^^^^^^^^^
+21. Clean-up of the ``model/`` directory.
+
+    a. Rearranged into subdirectories which include all dependencies.
+    #. Added descriptions in XML comments, cleaned up XMLs.
+    #. Deleted some composite models: ``grid1``, ``grid1pin``, ``grid2``, ``softcylinder``, ``softellipsoid``.
+
+#. Added descriptive animations in ``docs/images/models/`` :
+
+|humanoid|   |particle|
+
+
+Version 2.1.0 (Oct. 18, 2021)
+-----------------------------
 
 New features
 ^^^^^^^^^^^^
@@ -63,3 +162,8 @@ Earlier Versions
 ----------------
 
 For changelogs of earlier versions please see `roboti.us <https://www.roboti.us/download.html>`_.
+
+.. |humanoid| image:: images/models/humanoid.gif
+   :width: 270px
+.. |particle| image:: images/models/particle.gif
+   :width: 270px