Version 2.1.2: Python bindings, OBJ assets support, bugfixes.

PiperOrigin-RevId: 434731612
Change-Id: I0cfda3e7a3d1c72036764986efc252ffa1b8c6b0

python/mujoco/osmesa/__init__.py

@@ -0,0 +1,81 @@
+# Copyright 2018 The dm_control Authors
+#
+# 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.
+# ==============================================================================
+"""An OSMesa context for software-based OpenGL rendering."""
+
+import os
+
+PYOPENGL_PLATFORM = os.environ.get('PYOPENGL_PLATFORM')
+
+if not PYOPENGL_PLATFORM:
+  os.environ['PYOPENGL_PLATFORM'] = 'osmesa'
+elif PYOPENGL_PLATFORM.lower() != 'osmesa':
+  raise ImportError(
+      'Cannot use OSMesa rendering platform. '
+      'The PYOPENGL_PLATFORM environment variable is set to {!r} '
+      '(should be either unset or \'osmesa\').'
+      .format(PYOPENGL_PLATFORM))
+
+# pylint: disable=g-import-not-at-top
+from OpenGL import GL
+from OpenGL import osmesa
+from OpenGL.GL import arrays
+
+_DEPTH_BITS = 24
+_STENCIL_BITS = 8
+_ACCUM_BITS = 0
+
+
+class GLContext:
+  """An OSMesa context for software-based OpenGL rendering."""
+
+  def __init__(self, max_width, max_height):
+    """Initializes this OSMesa context."""
+    self._context = osmesa.OSMesaCreateContextExt(
+        osmesa.OSMESA_RGBA,
+        _DEPTH_BITS,
+        _STENCIL_BITS,
+        _ACCUM_BITS,
+        None,  # sharelist
+    )
+    if not self._context:
+      raise RuntimeError('Failed to create OSMesa GL context.')
+
+    self._height = max_height
+    self._width = max_width
+
+    # Allocate a buffer to render into.
+    self._buffer = arrays.GLfloatArray.zeros((max_height, max_width, 4))
+
+  def make_current(self):
+    if self._context:
+      success = osmesa.OSMesaMakeCurrent(
+          self._context,
+          self._buffer,
+          GL.GL_FLOAT,
+          self._width,
+          self._height)
+      if not success:
+        raise RuntimeError('Failed to make OSMesa context current.')
+
+  def free(self):
+    """Frees resources associated with this context."""
+    if self._context and self._context == osmesa.OSMesaGetCurrentContext():
+      osmesa.OSMesaMakeCurrent(None, None, GL.GL_FLOAT, 0, 0)
+    osmesa.OSMesaDestroyContext(self._context)
+    self._buffer = None
+    self._context = None
+
+  def __del__(self):
+    self.free()