EGL and NSOpenGL do not offer an EXT_swap_control_tear equivalent so
use regular vsync for now. The relevant extension string is now
correctly checked on WGL and GLX.
If SDL2 is supported, the PlatformFactory will now use it for creating the OpenGL ES context. Previously, it would revert to the native drivers when GraphicsContextFlag.Embedded was specified.
* EglContext.cs:
* EglGraphicsMode.cs: Added a parameter to indicate which ES renderer
version we wish to use. Fixes issue [#2247]: "CreateEGLGraphicsMode
should select the correct renderer".
* Source/OpenTK/Graphics/GraphicsContext.cs:
* Source/OpenTK/Graphics/IGraphicsContext.cs:
* Source/OpenTK/Platform/MacOS/AglContext.cs:
* Source/OpenTK/Platform/X11/X11GLContext.cs:
* Source/OpenTK/Graphics/GraphicsContextBase.cs:
* Source/OpenTK/Platform/Windows/WinGLContext.cs:
* Source/OpenTK/Platform/Dummy/DummyGLContext.cs: Added IsDisposed
property to IGraphicsContext and implemented in all context classes.
Removed 'bool disposed' fields from these classes in favor of the
new property.
Added GraphicsContextBase, which acts as the foundation of all IGraphicsContext implementations.
Added DesktopGraphicsContext, which acts as the foundation of all desktop (i.e. not ES) IGraphicsContext implementations.
Modified all IGraphicsContext implementations to inherit from GraphicsContextBase and/or DesktopGraphicsContext.
Removed OpenTK.Graphics.Glu class (reason: deprecated upstream; most functionality provided by OpenTK math; not compatible with OpenGL 3.0+.) OpenTK.Graphics.Glu can be accessed through OpenTK.Compatibility.
Added OpenGL|ES-specific ErrorHelper classes.
Moved OpenTK.Graphics.DisplayDevice and OpenTK.Graphics.DisplayResolution to the root OpenTK namespace (reason: their functionality is not specific and does not depend on OpenTK.Graphics).
Split Graphics*Exception classes into different files.
Made GraphicsErrorException public (reason: necessary for OpenTK.Compatibility).