Replace the Studio parser module with a pure Python implementation

PiperOrigin-RevId: 953181335
Change-Id: I1d2ce6f27f50aa4c30cce6d43caed80186ddef42

Author: okmatija

python/mujoco/experimental/studio/CMakeLists.txt

@@ -23,9 +23,6 @@ set(STUDIO_COMMON_LIBS
   structs_wrappers
 )
 
-mujoco_pybind11_module(parser parser.cc)
-target_link_libraries(parser PRIVATE ${STUDIO_COMMON_LIBS})
-
 mujoco_pybind11_module(native_viewer_cc native_viewer.cc)
 target_link_libraries(native_viewer_cc PRIVATE ${STUDIO_COMMON_LIBS})
 
@@ -39,7 +36,6 @@ mujoco_pybind11_module(sim sim.cc)
 target_link_libraries(sim PRIVATE ${STUDIO_COMMON_LIBS})
 
 set(MUJOCO_STUDIO_TARGETS
-    parser
     native_viewer_cc
     renderer
     ux
@@ -73,7 +69,6 @@ set_target_properties(implot PROPERTIES
 # when linking both GLFW (via Filament) and SDL2 statically on Linux.
 if(UNIX AND NOT APPLE)
   set(STUDIO_PY_MODULES
-      parser
       native_viewer_cc
       renderer
       ux
@@ -86,7 +81,6 @@ endif()
 
 if(APPLE)
   set(STUDIO_PY_MODULES
-      parser
       native_viewer_cc
       renderer
       ux

python/mujoco/experimental/studio/parser.cc

@@ -0,0 +1,24 @@
+# Copyright 2026 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
+#
+#     https://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.
+"""Loads and compiles MuJoCo models for the studio viewer."""
+
+import mujoco
+
+
+def parse(filepath: str) -> mujoco.MjData:
+  if filepath.endswith('.mjb'):
+    model = mujoco.MjModel.from_binary_path(filepath)
+  else:
+    model = mujoco.MjSpec.from_file(filepath).compile()
+  return mujoco.MjData(model)