# 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.

# ============================================================================

"""Extends OpenGL.EGL with definitions necessary for headless rendering."""

import ctypes

from OpenGL.platform import ctypesloader # pylint: disable=g-bad-import-order

try:

# Nvidia driver seems to need libOpenGL.so (as opposed to libGL.so)

# for multithreading to work properly. We load this in before everything else.

ctypesloader.loadLibrary(ctypes.cdll, 'OpenGL', mode=ctypes.RTLD_GLOBAL)

except OSError:

pass

# pylint: disable=g-import-not-at-top

from OpenGL import EGL

from OpenGL import error

# From the EGL_EXT_device_enumeration extension.

PFNEGLQUERYDEVICESEXTPROC = ctypes.CFUNCTYPE(

EGL.EGLBoolean,

EGL.EGLint,

ctypes.POINTER(EGL.EGLDeviceEXT),

ctypes.POINTER(EGL.EGLint),

)

try:

_eglQueryDevicesEXT = PFNEGLQUERYDEVICESEXTPROC( # pylint: disable=invalid-name

EGL.eglGetProcAddress('eglQueryDevicesEXT'))

except TypeError:

raise ImportError('eglQueryDevicesEXT is not available.')

# From the EGL_EXT_platform_device extension.

EGL_PLATFORM_DEVICE_EXT = 0x313F

PFNEGLGETPLATFORMDISPLAYEXTPROC = ctypes.CFUNCTYPE(

EGL.EGLDisplay, EGL.EGLenum, ctypes.c_void_p, ctypes.POINTER(EGL.EGLint))

try:

eglGetPlatformDisplayEXT = PFNEGLGETPLATFORMDISPLAYEXTPROC( # pylint: disable=invalid-name

EGL.eglGetProcAddress('eglGetPlatformDisplayEXT'))

except TypeError:

raise ImportError('eglGetPlatformDisplayEXT is not available.')

# Wrap raw _eglQueryDevicesEXT function into something more Pythonic.

def eglQueryDevicesEXT(max_devices=10): # pylint: disable=invalid-name

devices = (EGL.EGLDeviceEXT * max_devices)()

num_devices = EGL.EGLint()

success = _eglQueryDevicesEXT(max_devices, devices, num_devices)

if success == EGL.EGL_TRUE:

return [devices[i] for i in range(num_devices.value)]

else:

raise error.GLError(err=EGL.eglGetError(),

baseOperation=eglQueryDevicesEXT,

result=success)

# Expose everything from upstream so that

# we can use this as a drop-in replacement for OpenGL.EGL.

# pylint: disable=wildcard-import,g-bad-import-order

from OpenGL.EGL import *