Add batch support to MJX data bind.

PiperOrigin-RevId: 729033713
Change-Id: I331317a54a7882dc67bf329da8aeaff7246754e4

python/mujoco/introspect/mjxmacro.py

@@ -0,0 +1,43 @@
+# Copyright 2025 DeepMind Technologies Limited
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""Generate X macros for Mujoco structs."""
+
+from . import structs
+
+MJMODEL_S = structs.STRUCTS['mjModel']
+MJDATA_S = structs.STRUCTS['mjData']
+
+MJMODEL = dict()
+MJDATA = dict()
+
+for field in MJMODEL_S.fields:
+  if not isinstance(field, structs.StructFieldDecl):
+    continue
+  if field.array_extent is None:
+    continue
+  if len(field.array_extent) == 1:
+    MJMODEL[field.name] = (field.array_extent[0], '1')
+  else:
+    MJMODEL[field.name] = (field.array_extent[0], str(field.array_extent[1]))
+
+for field in MJDATA_S.fields:
+  if not isinstance(field, structs.StructFieldDecl):
+    continue
+  if field.array_extent is None:
+    continue
+  if len(field.array_extent) == 1:
+    MJDATA[field.name] = (field.array_extent[0], '1')
+  else:
+    MJDATA[field.name] = (field.array_extent[0], str(field.array_extent[1]))