From caec236b2f05567b7803d4674edae2ded749749b Mon Sep 17 00:00:00 2001
From: Haroon Qureshi <haroonq@google.com>
Date: Thu, 11 Dec 2025 01:23:03 -0800
Subject: [PATCH] Make mj_loadModelBuffer a public API.

PiperOrigin-RevId: 843105390
Change-Id: I4058471b4cf64995dd5ab43e9c8c24e322004b62
---
 doc/APIreference/functions.rst        |  9 +++++++++
 doc/includes/references.h             |  1 +
 include/mujoco/mujoco.h               |  3 +++
 python/mujoco/introspect/functions.py | 20 ++++++++++++++++++++
 src/engine/engine_io.h                |  4 ++--
 unity/Runtime/Bindings/MjBindings.cs  |  3 +++
 wasm/codegen/generators/constants.py  |  1 +
 7 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/doc/APIreference/functions.rst b/doc/APIreference/functions.rst
index 1095d16c..7b26f506 100644
--- a/doc/APIreference/functions.rst
+++ b/doc/APIreference/functions.rst
@@ -1475,6 +1475,15 @@ If vfs is not NULL, look up file in vfs before reading from disk.
 
 *Nullable:* ``vfs``
 
+.. _mj_loadModelBuffer:
+
+`mj_loadModelBuffer <#mj_loadModelBuffer>`__
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. mujoco-include:: mj_loadModelBuffer
+
+Load model from memory buffer.
+
 .. _mj_deleteModel:
 
 `mj_deleteModel <#mj_deleteModel>`__
diff --git a/doc/includes/references.h b/doc/includes/references.h
index 3193e820..cb9013d1 100644
--- a/doc/includes/references.h
+++ b/doc/includes/references.h
@@ -3096,6 +3096,7 @@ void mj_defaultVisual(mjVisual* vis);
 mjModel* mj_copyModel(mjModel* dest, const mjModel* src);
 void mj_saveModel(const mjModel* m, const char* filename, void* buffer, int buffer_sz);
 mjModel* mj_loadModel(const char* filename, const mjVFS* vfs);
+mjModel* mj_loadModelBuffer(const void* buffer, int buffer_sz);
 void mj_deleteModel(mjModel* m);
 mjtSize mj_sizeModel(const mjModel* m);
 mjData* mj_makeData(const mjModel* m);
diff --git a/include/mujoco/mujoco.h b/include/mujoco/mujoco.h
index da43efc5..1d517431 100644
--- a/include/mujoco/mujoco.h
+++ b/include/mujoco/mujoco.h
@@ -212,6 +212,9 @@ MJAPI void mj_saveModel(const mjModel* m, const char* filename, void* buffer, in
 // Nullable: vfs
 MJAPI mjModel* mj_loadModel(const char* filename, const mjVFS* vfs);
 
+// Load model from memory buffer.
+MJAPI mjModel* mj_loadModelBuffer(const void* buffer, int buffer_sz);
+
 // Free memory allocation in model.
 MJAPI void mj_deleteModel(mjModel* m);
 
diff --git a/python/mujoco/introspect/functions.py b/python/mujoco/introspect/functions.py
index b10979f4..4110a182 100644
--- a/python/mujoco/introspect/functions.py
+++ b/python/mujoco/introspect/functions.py
@@ -839,6 +839,26 @@ FUNCTIONS: Mapping[str, FunctionDecl] = dict([
          ),
          doc='Load model from binary MJB file. If vfs is not NULL, look up file in vfs before reading from disk.',  # pylint: disable=line-too-long
      )),
+    ('mj_loadModelBuffer',
+     FunctionDecl(
+         name='mj_loadModelBuffer',
+         return_type=PointerType(
+             inner_type=ValueType(name='mjModel'),
+         ),
+         parameters=(
+             FunctionParameterDecl(
+                 name='buffer',
+                 type=PointerType(
+                     inner_type=ValueType(name='void', is_const=True),
+                 ),
+             ),
+             FunctionParameterDecl(
+                 name='buffer_sz',
+                 type=ValueType(name='int'),
+             ),
+         ),
+         doc='Load model from memory buffer.',
+     )),
     ('mj_deleteModel',
      FunctionDecl(
          name='mj_deleteModel',
diff --git a/src/engine/engine_io.h b/src/engine/engine_io.h
index a2d7bc34..a5410f86 100644
--- a/src/engine/engine_io.h
+++ b/src/engine/engine_io.h
@@ -69,8 +69,8 @@ MJAPI void mjv_copyModel(mjModel* dest, const mjModel* src);
 // save model to binary file
 MJAPI void mj_saveModel(const mjModel* m, const char* filename, void* buffer, int buffer_sz);
 
-// load binary MJB
-mjModel* mj_loadModelBuffer(const void* buffer, int buffer_sz);
+// load model from binary buffer
+MJAPI mjModel* mj_loadModelBuffer(const void* buffer, int buffer_sz);
 
 // deallocate model
 MJAPI void mj_deleteModel(mjModel* m);
diff --git a/unity/Runtime/Bindings/MjBindings.cs b/unity/Runtime/Bindings/MjBindings.cs
index 09123d88..0553fd8a 100644
--- a/unity/Runtime/Bindings/MjBindings.cs
+++ b/unity/Runtime/Bindings/MjBindings.cs
@@ -6444,6 +6444,9 @@ public static unsafe extern void mj_saveModel(mjModel_* m, [MarshalAs(UnmanagedT
 [DllImport("mujoco", CallingConvention = CallingConvention.Cdecl)]
 public static unsafe extern mjModel_* mj_loadModel([MarshalAs(UnmanagedType.LPStr)]string filename, void* vfs);
 
+[DllImport("mujoco", CallingConvention = CallingConvention.Cdecl)]
+public static unsafe extern mjModel_* mj_loadModelBuffer(void* buffer, int buffer_sz);
+
 [DllImport("mujoco", CallingConvention = CallingConvention.Cdecl)]
 public static unsafe extern void mj_deleteModel(mjModel_* m);
 
diff --git a/wasm/codegen/generators/constants.py b/wasm/codegen/generators/constants.py
index f4a55f5e..1cb0ef23 100644
--- a/wasm/codegen/generators/constants.py
+++ b/wasm/codegen/generators/constants.py
@@ -139,6 +139,7 @@ _SKIPPED_MEMORY_FUNCTIONS: tuple[str, ...] = (
     "mj_freeLastXML",
     "mj_freeStack",
     "mj_loadModel",
+    "mj_loadModelBuffer",
     "mj_markStack",
     "mj_saveModel",
     "mj_stackAllocByte",