Support setting backend parameters using env vars

CHANGELOG.md

@@ -1,6 +1,16 @@
 
 # Change Log
 
+## 2.0.1
+
+* Support setting backend arguments using environment variables.
+  * `GLCONTEXT_GLVERSION` for setting opengl version
+  * `GLCONTEXT_LINUX_LIBGL` for specifying libgl name
+  * `GLCONTEXT_LINUX_LIBX11` for specifying libx11 name
+  * `GLCONTEXT_LINUX_LIBEGL` for specifying libegl name
+  * `GLCONTEXT_WIN_LIBGL` for specifying dll name
+* x11: More details in error messages
+
 ## 2.0.0
 
 Support passing in values to backends for more detailed

README.md

@@ -129,6 +129,24 @@ Parameters
 * `libgl` (`str`): Name of gl library to load (default: `libGL.so`)
 * `libegl` (`str`): Name of gl library to load (default: `libEGL.so`)
 
+## Environment Variables
+
+Environment variables can be set to configure backends.
+These will get first priority if defined.
+
+```bash
+# Override OpenGL version code. For example: 410 (for opengl 4.1)
+GLCONTEXT_GLVERSION
+# Override libgl on linux. For example: libGL.1.so
+GLCONTEXT_LINUX_LIBGL
+# Override libx11 on linux. For exampleØ libX11.x.so
+GLCONTEXT_LINUX_LIBX11
+# Override libegl on linux. For exampleØ libEGL.x.so
+GLCONTEXT_LINUX_LIBEGL
+# Override gl dll on windows. For example: opengl32_custom.dll
+GLCONTEXT_WIN_LIBGL
+```
+
 ## Running tests
 
 ```

glcontext/__init__.py

@@ -1,4 +1,6 @@
-__version__ = '2.0.0'
+import os
+
+__version__ = '2.1.0'
 
 
 def default_backend():
@@ -54,33 +56,48 @@ def _wgl():
     from glcontext import wgl
 
     def create(*args, **kwargs):
-        supported_args = ['glversion', 'mode', 'libgl']
-        return wgl.create_context(**_strip_kwargs(kwargs, supported_args))
+        _apply_env_var(kwargs, 'glversion', 'GLCONTEXT_GLVERSION', arg_type=int)
+        _apply_env_var(kwargs, 'libgl', 'GLCONTEXT_WIN_LIBGL')
+        kwargs = _strip_kwargs(kwargs, ['glversion', 'mode', 'libgl'])
+        return wgl.create_context(**kwargs)
 
     return create
 
 
 def _x11():
     """Create x11 backend"""
     from glcontext import x11
+
     def create(*args, **kwargs):
-        supported_args = ['glversion', 'mode', 'libgl', 'libx11']
-        return x11.create_context(**_strip_kwargs(kwargs, supported_args))
+        _apply_env_var(kwargs, 'glversion', 'GLCONTEXT_GLVERSION', arg_type=int)
+        _apply_env_var(kwargs, 'libgl', 'GLCONTEXT_LINUX_LIBGL')
+        _apply_env_var(kwargs, 'libx11', 'GLCONTEXT_LINUX_LIBX11')
+        kwargs = _strip_kwargs(kwargs, ['glversion', 'mode', 'libgl', 'libx11'])
+        return x11.create_context(**kwargs)
+
     return create
 
+
 def _darwin():
     """Create darwin/cgl context"""
     from glcontext import darwin
+
     def create(*args, **kwargs):
-        supported_args = ['mode']
-        return darwin.create_context(**_strip_kwargs(kwargs, supported_args))
+        return darwin.create_context(**_strip_kwargs(kwargs, ['mode']))
+
     return create
 
+
 def _egl():
     from glcontext import egl
+
     def create(*args, **kwargs):
-        supported_args = ['glversion', 'mode', 'libgl', 'libegl']
-        return egl.create_context(**_strip_kwargs(kwargs, supported_args))
+        _apply_env_var(kwargs, 'glversion', 'GLCONTEXT_GLVERSION', arg_type=int)
+        _apply_env_var(kwargs, 'libgl', 'GLCONTEXT_LINUX_LIBGL')
+        _apply_env_var(kwargs, 'libegl', 'GLCONTEXT_LINUX_LIBEGL')
+        kwargs = _strip_kwargs(kwargs, ['glversion', 'mode', 'libgl', 'libegl'])
+        return egl.create_context(**kwargs)
+
     return create
 
 
@@ -95,3 +112,10 @@ def _strip_kwargs(kwargs: dict, supported_args: list):
         - Removes unsupported arguments
     """
     return {k: v for k, v in kwargs.items() if v is not None and k in supported_args}
+
+
+def _apply_env_var(kwargs, arg_name, env_name, arg_type=str):
+    """Injects an environment variable into the arg dict if present"""
+    value = os.environ.get(env_name, kwargs.get(arg_name))
+    if value:
+        kwargs[arg_name] = arg_type(value)

setup.py

@@ -58,7 +58,7 @@
 
 setup(
     name='glcontext',
-    version='2.0.0',
+    version='2.1.0',
     description='Portable OpenGL Context',
     long_description=open('README.md').read(),
     long_description_content_type='text/markdown',