Add Renderer class to Python native bindings.

PiperOrigin-RevId: 492994751
Change-Id: Iebbe5980668a15b1cd62c0076cc131255462b2eb

python/mujoco/renderer_test.py

@@ -0,0 +1,50 @@
+# Copyright 2022 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.
+# ==============================================================================
+"""Tests for the MuJoCo renderer."""
+
+from absl.testing import absltest
+from absl.testing import parameterized
+import mujoco
+
+
+@absltest.skipUnless(hasattr(mujoco, 'GLContext'),
+                     'MuJoCo rendering is disabled')
+class MuJoCoRendererTest(parameterized.TestCase):
+  def test_renderer_renders_scene(self):
+    xml = """
+ <mujoco>
+  <worldbody>
+    <camera name="closeup" pos="0 -6 0" xyaxes="1 0 0 0 1 100"/>
+    <geom name="white_box" type="box" size="1 1 1" rgba="1 1 1 1"/>
+  </worldbody>
+</mujoco>
+"""
+    model = mujoco.MjModel.from_xml_string(xml)
+    data = mujoco.MjData(model)
+    renderer = mujoco.Renderer(model, 50, 50)
+    mujoco.mj_forward(model, data)
+    renderer.update_scene(data, 'closeup')
+
+    pixels = renderer.render().flatten()
+    not_all_black = False
+
+    # Pixels should all be a neutral color.
+    for pixel in pixels:
+      if pixel > 0:
+        not_all_black = True
+        break
+    self.assertTrue(not_all_black)
+if __name__ == '__main__':
+  absltest.main()