SDL/docs/README-windows.md

# Windows

## OpenGL ES 2.x support

SDL has support for OpenGL ES 2.x under Windows via two alternative
implementations.

The most straightforward method consists in running your app in a system with
a graphic card paired with a relatively recent (as of November of 2013) driver
which supports the WGL_EXT_create_context_es2_profile extension. Vendors known
to ship said extension on Windows currently include nVidia and Intel.

The other method involves using the
[ANGLE library](https://code.google.com/p/angleproject/). If an OpenGL ES 2.x
context is requested and no WGL_EXT_create_context_es2_profile extension is
found, SDL will try to load the libEGL.dll library provided by ANGLE.

To obtain the ANGLE binaries, you can either compile from source from
https://chromium.googlesource.com/angle/angle or copy the relevant binaries
from a recent Chrome/Chromium install for Windows. The files you need are:

- libEGL.dll
- libGLESv2.dll
- d3dcompiler_46.dll (supports Windows Vista or later, better shader
  compiler) *or* d3dcompiler_43.dll (supports Windows XP or later)
    
If you compile ANGLE from source, you can configure it so it does not need the
d3dcompiler_* DLL at all (for details on this, see their documentation).
However, by default SDL will try to preload the d3dcompiler_46.dll to
comply with ANGLE's requirements. If you wish SDL to preload
d3dcompiler_43.dll (to support Windows XP) or to skip this step at all, you
can use the SDL_HINT_VIDEO_WIN_D3DCOMPILER hint (see SDL_hints.h for more
details).

Known Bugs:

- SDL_GL_SetSwapInterval is currently a no op when using ANGLE. It appears
  that there's a bug in the library which prevents the window contents from
  refreshing if this is set to anything other than the default value.
  
## Vulkan Surface Support

Support for creating Vulkan surfaces is configured on by default. To disable
it change the value of `SDL_VIDEO_VULKAN` to 0 in `SDL_config_windows.h`. You
must install the [Vulkan SDK](https://www.lunarg.com/vulkan-sdk/) in order to
use Vulkan graphics in your application.