* Added SDL_GL_ResetAttributes() to reset OpenGL attributes to default values
* Added an API to load a database of game controller mappings from a file:
* Added game controller mappings for the PS4 and OUYA controllers
* Added SDL_GetDefaultAssertionHandler() and SDL_GetAssertionHandler()
* Added SDL_DetachThread()
* Added SDL_HasAVX() to determine if the CPU has AVX features
* Added SDL_vsscanf(), SDL_acos(), and SDL_asin() to the stdlib routines
* EGL can now create/manage OpenGL and OpenGL ES 1.x/2.x contexts, and share
them using SDL_GL_SHARE_WITH_CURRENT_CONTEXT
* Added a field "clicks" to the mouse button event which records whether the event is a single click, double click, etc.
* The screensaver is now disabled by default, and there is a hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER that can change that behavior.
* Added a hint SDL_HINT_MOUSE_RELATIVE_MODE_WARP to specify whether mouse relative mode should be emulated using mouse warping.
* testgl2 does not need to link with libGL anymore
* Added testgles2 test program to demonstrate working with OpenGL ES 2.0
* Added controllermap test program to visually map a game controller
* Support for OpenGL ES 2.x contexts using either WGL or EGL (natively via
the driver or emulated through ANGLE)
* Added a hint SDL_HINT_VIDEO_WIN_D3DCOMPILER to specify which D3D shader compiler to use for OpenGL ES 2 support through ANGLE
* Added a hint SDL_HINT_VIDEO_WINDOW_SHARE_PIXEL_FORMAT that is useful when creating multiple windows that should share the same OpenGL context.
* Added an event SDL_RENDER_TARGETS_RESET that is sent when D3D9 render targets are reset after the device has been restored.
Mac OS X:
* Fullscreen desktop mode now uses spaces for a more fluid Mac experience.
* Added a hint SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK to control whether Ctrl+click should be treated as a right click on Mac OS X. This is off by default.
* Fixed fullscreen and focused behavior when receiving NotifyGrab events
* Added experimental Wayland and Mir support, disabled by default
* Joystick support (minimum SDK version required to build SDL is now 12,
the required runtime version remains at 10, but on such devices joystick
support won't be available).
* Hotplugging support for joysticks
* Added a hint SDL_HINT_ACCELEROMETER_AS_JOYSTICK to control whether the accelerometer should be listed as a 3 axis joystick, which it will by default.