Add mj_copyState

PiperOrigin-RevId: 836588419
Change-Id: I7609e121dc0ac697d4d015d4244bdd5962650def

python/mujoco/bindings_test.py

@@ -806,6 +806,13 @@ class MuJoCoBindingsTest(parameterized.TestCase):
     # Expect next states to be equal.
     np.testing.assert_array_equal(state1a, state1b)
 
+    # Test mj_copyState
+    data2 = mujoco.MjData(self.model)
+    mujoco.mj_copyState(self.model, self.data, data2, sig)
+    state1c = np.empty(size, np.float64)
+    mujoco.mj_getState(self.model, data2, state1c, sig)
+    np.testing.assert_array_equal(state1a, state1c)
+
   def test_mj_setKeyframe(self):  # pylint: disable=invalid-name
     mujoco.mj_step(self.model, self.data)
 

python/mujoco/functions.cc

@@ -350,6 +350,7 @@ PYBIND11_MODULE(_functions, pymodule) {
         }
         return InterceptMjErrors(::mj_setState)(m, d, state.data(), sig);
       });
+  Def<traits::mj_copyState>(pymodule);
   Def<traits::mj_setKeyframe>(pymodule);
   Def<traits::mj_addContact>(pymodule);
   Def<traits::mj_isPyramidal>(pymodule);

python/mujoco/introspect/functions.py

@@ -2520,6 +2520,36 @@ FUNCTIONS: Mapping[str, FunctionDecl] = dict([
          ),
          doc='Set state.',
      )),
+    ('mj_copyState',
+     FunctionDecl(
+         name='mj_copyState',
+         return_type=ValueType(name='void'),
+         parameters=(
+             FunctionParameterDecl(
+                 name='m',
+                 type=PointerType(
+                     inner_type=ValueType(name='mjModel', is_const=True),
+                 ),
+             ),
+             FunctionParameterDecl(
+                 name='src',
+                 type=PointerType(
+                     inner_type=ValueType(name='mjData', is_const=True),
+                 ),
+             ),
+             FunctionParameterDecl(
+                 name='dst',
+                 type=PointerType(
+                     inner_type=ValueType(name='mjData'),
+                 ),
+             ),
+             FunctionParameterDecl(
+                 name='sig',
+                 type=ValueType(name='unsigned int'),
+             ),
+         ),
+         doc='Copy state from src to dst.',
+     )),
     ('mj_setKeyframe',
      FunctionDecl(
          name='mj_setKeyframe',