Expose mj_makeM as a sub-component.

PiperOrigin-RevId: 763662068
Change-Id: I55ced456dca751c1de09fb35e2f73c60ffc0d626

doc/APIreference/functions.rst

@@ -748,8 +748,7 @@ Compare forward and inverse dynamics, save results in fwdinv.
 Sub components
 ^^^^^^^^^^^^^^
 
-These are sub-components of the simulation pipeline, called internally from the components above. It is very unlikely
-that the user will need to call them.
+These are sub-components of the simulation pipeline, called internally from the components above.
 
 .. _mj_sensorPos:
 
@@ -886,6 +885,18 @@ Compute actuator transmission lengths and moments.
 
 Run composite rigid body inertia algorithm (CRB).
 
+.. _mj_makeM:
+
+`mj_makeM <#mj_makeM>`__
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mj_makeM
+
+Compute the composite rigid body inertia with :ref:`mj_crb`, add terms due
+to :ref:`tendon armature<tendon-spatial-armature>`. The joint-space inertia matrix is stored in both ``mjData.qM`` and
+``mjData.M``. These arrays represent the same quantity using different layouts (parent-based and compressed sparse row,
+respectively).
+
 .. _mj_factorM:
 
 `mj_factorM <#mj_factorM>`__

doc/APIreference/functions_override.rst

@@ -113,8 +113,14 @@ Integrates the simulation state using an implicit-in-velocity integrator (either
 
 .. _Subcomponents:
 
-These are sub-components of the simulation pipeline, called internally from the components above. It is very unlikely
-that the user will need to call them.
+These are sub-components of the simulation pipeline, called internally from the components above.
+
+.. _mj_makeM:
+
+Compute the composite rigid body inertia with :ref:`mj_crb`, add terms due
+to :ref:`tendon armature<tendon-spatial-armature>`. The joint-space inertia matrix is stored in both ``mjData.qM`` and
+``mjData.M``. These arrays represent the same quantity using different layouts (parent-based and compressed sparse row,
+respectively).
 
 .. _mj_factorM: