Coriiander
There's a slight mistake in the function "GetWindowStyle" found in file "SDL_windowswindow.c".
When a window is marked to be resizable, the resizable style is being added regardless of whether the window has a border or not. While for some arcane, hidden semantics this can be ok, it's still inconsistent in this case.
Mark Callow
The attached patch does the following for the X11 and Windows platforms, the only ones where SDL attempts to use context_create_es_profile:
- Adds SDL_HINT_OPENGL_ES_DRIVER by which the application can
say to use the OpenGL ES driver & EGL rather than the Open GL
driver. (For bug #2570)
- Adds code to {WIN,X11}_GL_InitExtensions to determine the maximum
OpenGL ES version supported by the OpenGL driver (for bug #3145)
- Modifies the test that determines whether to use the OpenGL
driver or the real OpenGL ES driver to take into account the
hint, the requested and supported ES version and whether ES 1.X
is being requested. (For bug #2570 & bug #3145)
- Enables the testgles2 test for __WINDOWS__ and __LINUX__ and adds
the test to the VisualC projects.
With the fix in place I have run testdraw2, testgl and testgles2 without any issues and have run my own apps that use OpenGL, OpenGL ES 3 and OpenGL ES 1.1.
realitix
SDL2 allows to create widow and to get information through SDL_SysWMinfo.
But it misses something, with Vulkan, you need the HWND and HINSTANCE of the window for Win32 system.
Sadly, SDL2 provides only HWND but not HINSTANCE.
In some context, it can be difficult to get the HINSTANCE, indeed, I'm using pySDL2 (Python) and I can only access properties that SDL2 gives me.
I have to use a dirty trick like that to get the HINSTANCE: (https://raw.githubusercontent.com/bglgwyng/pyVulkan/master/examples/win32misc.py)
This is currently implemented for X11, Cocoa, Windows, and DirectFB.
This patch is based on work in Unreal Engine 4's fork of SDL,
compliments of Epic Games.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().