If OpenGL 3.x doesn't work, the fallback to legacy GL will call the
function to create the DC again, and it will assert. Just make it not
to, and also simplify the code a bit.
Fixes#974.
CS_OWNDC will make GetDC() always return the same HDC. This might
become a problem when OpenGL rendering and window management are
on different threads. Although I'm not too sure about this; our
code never requests a HDC outside of the OpenGL backend, and it
depends on whether win32 will internally request DCs. But in any
case, this seems to be cleaner.
Move the GL pixelformat setup code to gl_w32.c, where it's actually
needed. This also fixes that SetPixelFormat() should be called only
once, and not every time video params change.
Preparation for moving win32 windowing to a separate thread.
The codesize is reduced a bit, because some small functions are
inlined, which reduces noise.
The main change is that now most functions use the private struct
directly, instead of accessing it indirectly through vo->w32.
Accesses to vo are minimalized.
The final goal is adding some sort of new windowing backend API. It
would be cleaner to use that as context pointer for all functions
(like struct vo was previously used), but since this is work in
progress, we just go with this commit.
Instead of having separate callbacks for each backend-handled feature
(like MPGLContext.fullscreen, MPGLContext.border, etc.), pass the
VOCTRL responsible for this directly to the backend. This allows
removing a bunch of callbacks, that currently must be set even for
optional/lesser features (like VOCTRL_BORDER).
This requires changes to all VOs using gl_common, as well as all
backends that support gl_common.
Also introduce VOCTRL_CHECK_EVENTS. vo.check_events is now optional.
VO backends can use VOCTRL_CHECK_EVENTS instead to implementing
check_events. This has the advantage that the event handling code in
VOs doesn't have to be duplicated if vo_control() is used.
Do this instead of stuffing all x11/cocoa/win32/wayland specific code
into gl_common.c. The cocoa specific parts could probably go directly
into cocoa_common.m, possibly same with wayland.
Also redo how the list of backends is managed. Get rid of the GLTYPE_
constants. Instead of having a big switch() on GLTYPE_, each backend
entry has a function pointer to setup the MPGLContext callback (e.g.
mpgl_set_backend_x11()).
