Add mjSpec bindings.

Co-authored-by: Saran Tunyasuvunakool <stunya@google.com>
PiperOrigin-RevId: 648444641
Change-Id: I08ee1d3f4fae1efbc7934ba94702b1c06d8cb92a

doc/APIreference/functions.rst

@@ -4167,6 +4167,69 @@ mjs_nextChild
 
 Return body's next child of the same type; return NULL if child is last.
 
+.. _mjs_asBody:
+
+mjs_asBody
+~~~~~~~~~~
+
+.. mujoco-include:: mjs_asBody
+
+Safely cast an element as mjsBody, or return NULL if the element is not an mjsBody.
+
+.. _mjs_asGeom:
+
+mjs_asGeom
+~~~~~~~~~~
+
+.. mujoco-include:: mjs_asGeom
+
+Safely cast an element as mjsGeom, or return NULL if the element is not an mjsGeom.
+
+.. _mjs_asJoint:
+
+mjs_asJoint
+~~~~~~~~~~~
+
+.. mujoco-include:: mjs_asJoint
+
+Safely cast an element as mjsJoint, or return NULL if the element is not an mjsJoint.
+
+.. _mjs_asSite:
+
+mjs_asSite
+~~~~~~~~~~
+
+.. mujoco-include:: mjs_asSite
+
+Safely cast an element as mjsSite, or return NULL if the element is not an mjsSite.
+
+.. _mjs_asCamera:
+
+mjs_asCamera
+~~~~~~~~~~~~
+
+.. mujoco-include:: mjs_asCamera
+
+Safely cast an element as mjsCamera, or return NULL if the element is not an mjsCamera.
+
+.. _mjs_asLight:
+
+mjs_asLight
+~~~~~~~~~~~
+
+.. mujoco-include:: mjs_asLight
+
+Safely cast an element as mjsLight, or return NULL if the element is not an mjsLight.
+
+.. _mjs_asFrame:
+
+mjs_asFrame
+~~~~~~~~~~~
+
+.. mujoco-include:: mjs_asFrame
+
+Safely cast an element as mjsFrame, or return NULL if the element is not an mjsFrame.
+
 .. _AttributeSetters:
 
 Attribute setters

doc/changelog.rst

@@ -26,7 +26,6 @@ General
    Still missing:
 
    - Detailed documentation.
-   - Python bindings.
 
 .. youtube:: ZXBTEIDWHhs
    :align: right

doc/includes/references.h

@@ -3544,6 +3544,13 @@ mjsDefault* mjs_getSpecDefault(mjSpec* s);
 int mjs_getId(mjsElement* element);
 mjsElement* mjs_firstChild(mjsBody* body, mjtObj type);
 mjsElement* mjs_nextChild(mjsBody* body, mjsElement* child);
+mjsBody* mjs_asBody(mjsElement* element);
+mjsGeom* mjs_asGeom(mjsElement* element);
+mjsJoint* mjs_asJoint(mjsElement* element);
+mjsSite* mjs_asSite(mjsElement* element);
+mjsCamera* mjs_asCamera(mjsElement* element);
+mjsLight* mjs_asLight(mjsElement* element);
+mjsFrame* mjs_asFrame(mjsElement* element);
 void mjs_setString(mjString* dest, const char* text);
 void mjs_setStringVec(mjStringVec* dest, const char* text);
 mjtByte mjs_setInStringVec(mjStringVec* dest, int i, const char* text);