Add mj_stackAllocInt to get correct size for allocating ints on mjData stack. Reducing stack memory usage by 10% - 15%.

PiperOrigin-RevId: 517672195
Change-Id: Ie14e6c9c99e8b9e1c5d3686b77631f2df0651c67

doc/APIreference/functions.rst

@@ -1187,7 +1187,16 @@ mj_stackAlloc
 
 .. mujoco-include:: mj_stackAlloc
 
-Allocate array of specified size on :ref:`mjData` stack. Call mju_error on stack overflow.
+Allocate array of mjtNums on :ref:`mjData` stack. Call mju_error on stack overflow.
+
+.. _mj_stackAllocInt:
+
+mj_stackAllocInt
+~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mj_stackAllocInt
+
+Allocate array of ints on :ref:`mjData` stack. Call mju_error on stack overflow.
 
 .. _mj_deleteData:
 

doc/changelog.rst

@@ -48,6 +48,8 @@ General
 - Modified :ref:`mju_error` and :ref:`mju_warning` to be variadic functions (support for printf-like arguments). The
   functions :ref:`mju_error_i`, :ref:`mju_error_s`, :ref:`mju_warning_i`, and :ref:`mju_warning_s` are now deprecated.
 - Implemented a performant ``mju_sqrMatTDSparse`` function that doesn't require dense memory allocation.
+- Added ``mj_stackAllocInt`` to get correct size for allocating ints on mjData stack. Reducing stack memory usage
+  by 10% - 15%.
 
 
 Python bindings

doc/includes/references.h

@@ -1873,6 +1873,7 @@ void mj_resetData(const mjModel* m, mjData* d);
 void mj_resetDataDebug(const mjModel* m, mjData* d, unsigned char debug_value);
 void mj_resetDataKeyframe(const mjModel* m, mjData* d, int key);
 mjtNum* mj_stackAlloc(mjData* d, int size);
+int* mj_stackAllocInt(mjData* d, int size);
 void mj_deleteData(mjData* d);
 void mj_resetCallbacks(void);
 void mj_setConst(mjModel* m, mjData* d);