Add support for querying of MjsTendon path from Python.

Fixes #2670

PiperOrigin-RevId: 822215254
Change-Id: Ice5a264e54f963776093511c6e4ac830aae6d4f8

doc/APIreference/functions.rst

@@ -4388,6 +4388,42 @@ Return spec's first element of selected type.
 
 Return spec's next element; return NULL if element is last.
 
+.. _mjs_getWrapTarget:
+
+`mjs_getWrapTarget <#mjs_getWrapTarget>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrapTarget
+
+Get wrapped element in tendon path.
+
+.. _mjs_getWrapSideSite:
+
+`mjs_getWrapSideSite <#mjs_getWrapSideSite>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrapSideSite
+
+Get wrapped element side site in tendon path if it has one, nullptr otherwise.
+
+.. _mjs_getWrapDivisor:
+
+`mjs_getWrapDivisor <#mjs_getWrapDivisor>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrapDivisor
+
+Get divisor of mjsWrap wrapping a puller.
+
+.. _mjs_getWrapCoef:
+
+`mjs_getWrapCoef <#mjs_getWrapCoef>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrapCoef
+
+Get coefficient of mjsWrap wrapping a joint.
+
 .. _AttributeSetters:
 
 Attribute setters
@@ -4533,6 +4569,24 @@ Get double array contents and optionally its size.
 
 *Nullable:* ``size``
 
+.. _mjs_getWrapNum:
+
+`mjs_getWrapNum <#mjs_getWrapNum>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrapNum
+
+Get number of elements a tendon wraps.
+
+.. _mjs_getWrap:
+
+`mjs_getWrap <#mjs_getWrap>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_getWrap
+
+Get mjsWrap element at position i in the tendon path.
+
 .. _mjs_getPluginAttributes:
 
 `mjs_getPluginAttributes <#mjs_getPluginAttributes>`__

doc/changelog.rst

@@ -12,6 +12,15 @@ General
 - Increase Windows stack size to 16MB to enable models with deep nested body hierarchies.
 - Added a new :ref:`mj_extractState` function that allows a subset of a state that was previously returned by
   :ref:`mj_getState` to be extracted without having to be written back into ``mjData`` first.
+- Tendon paths can now be queried from Python via ``MjsTendon.path``, the returned object
+  is iterable and indexing it will give the ``MjsWrap`` at the given index in the path.
+- ``MjsWrap`` now exposes:
+
+  - ``type -> mujoco.mjtWrap``
+  - ``target -> MjsSite|MjsJoint|MjsGeom|None``
+  - ``sidesite -> MjsSite|None``
+  - ``coef -> real``
+  - ``divisor -> real``
 
 Version 3.3.7 (October 13, 2025)
 -----------------------------------

doc/includes/references.h

@@ -3500,6 +3500,10 @@ mjsElement* mjs_firstChild(mjsBody* body, mjtObj type, int recurse);
 mjsElement* mjs_nextChild(mjsBody* body, mjsElement* child, int recurse);
 mjsElement* mjs_firstElement(mjSpec* s, mjtObj type);
 mjsElement* mjs_nextElement(mjSpec* s, mjsElement* element);
+mjsElement* mjs_getWrapTarget(mjsWrap* wrap);
+mjsSite* mjs_getWrapSideSite(mjsWrap* wrap);
+double mjs_getWrapDivisor(mjsWrap* wrap);
+double mjs_getWrapCoef(mjsWrap* wrap);
 int mjs_setName(mjsElement* element, const char* name);
 void mjs_setBuffer(mjByteVec* dest, const void* array, int size);
 void mjs_setString(mjString* dest, const char* text);
@@ -3515,6 +3519,8 @@ void mjs_setPluginAttributes(mjsPlugin* plugin, void* attributes);
 mjString* mjs_getName(mjsElement* element);
 const char* mjs_getString(const mjString* source);
 const double* mjs_getDouble(const mjDoubleVec* source, int* size);
+int mjs_getWrapNum(const mjsTendon* tendonspec);
+mjsWrap* mjs_getWrap(const mjsTendon* tendonspec, int i);
 const void* mjs_getPluginAttributes(const mjsPlugin* plugin);
 void mjs_setDefault(mjsElement* element, const mjsDefault* def);
 int mjs_setFrame(mjsElement* dest, mjsFrame* frame);