For some reason Wayland thought it would be clever to be the only
windowing system that (non-optionally) uses the alpha chan of the
window's default OpenGL framebuffer for window transparency.
This always caused glitches with dhewm3, as Doom3 uses that alpha-chan
for blending tricks (with GL_DST_ALPHA) - especially visible in the main
menu or when the flashlight is on.
So far the workaround has been r_waylandcompat which requests an OpenGL
context/visual without alpha chan (0 alpha bits), but that also causes
glitches.
There's an EGL extension that's supposed to fix this issue
(EGL_EXT_present_opaque), and newer SDL2 versions use it (when using
the wayland backend) - but unfortunately the Mesa implementation is
broken (seems to provide a visual without alpha channel even if one was
requested), see https://gitlab.freedesktop.org/mesa/mesa/-/issues/5886
and https://github.com/libsdl-org/SDL/pull/4306#issuecomment-1014770600
for the corresponding SDL2 discussion
To work around this issue, dhewm3 now disables the use of that EGL
extension and (optionally) makes sure the alpha channel is opaque at
the end of the frame.
This behavior is controlled with the r_fillWindowAlphaChan CVar:
If it's 1, this always is done (regardless if wayland is used or not),
if it's 0 it's not done (even on wayland),
if it's -1 (the default) it's only done if the SDL "video driver" is
wayland (this could be easily enhanced later in case other windowing
systems have the same issue)
r_waylandcompat has been removed (it never worked properly anyway),
so now the window always has an alpha chan
so if someone configured 16x AA on a system that doesn't support it
(like when using AMDs open source driver), 8x will be tried before
falling back to a 640x480 window with no AA at all.
(and then it'll try 4x and then 2x and then no AA at all, and only then
reducing color depth will start, and even later it'll fall back to
a small 640x480 window)
There were lots of places in the code that called Sys_GrabInput(),
some of them each frame.
Most of this is unified in events.cpp now, in handleMouseGrab() which
is called once per frame by Sys_GenerateEvents() - this makes reasoning
about when the mouse is grabbed and when not a lot easier.
Sys_GrabInput(false) still is called in a few places, before operations
that tend to take long (like loading a map or vid_restart), but
(hopefully) not regularly anymore.
The other big change is that the game now uses SDLs absolute mouse mode
for fullscreen menus (except the PDA which is an ugly hack), so the
ingame cursor is at the same position as the system cursor, which
especially helps when debugging with `in_nograb 1` and should also help
if someone wants to integrate an additional GUI toolkit like Dear ImGui.
- Fix build with SDL <=2.0.3
SDL_GetGlobalMouseState was introduced in 2.0.4
(which doesn't support OSX 10.5 or older)
- Don't include execinfo.h on Mac OS X 10.4
This file isn't included in the 10.4 SDK
- Use custom typedef for PFNGLSTENCILOPSEPARATEPROC on OSX 10.4/10.5
because the system OpenGL headers for those versions don't have it
The problem was that the editors called ChoosePixelFormat() instead of
wglChoosePixelFormatARB() - and the normal ChoosePixelFormat() has no
attribute for MSAA, so if MSAA is enabled (by SDL2 which calls the wgl
variant), ChoosePixelFormat() will return an incomaptible format and
the editors don't get a working OpenGL context.
So I wrote a wrapper around ChoosePixelFormat() that calls the wgl variant
if available, and all the necessary plumbing around that.
While at it, removed the unused qwgl*PixelFormat function pointers and
supressed the "inconsistent dll linkage" warnings for the gl stubs
I updated sdl2-config.cmake in dhewm3-libs so building on Windows with
them works again, however that required also a little change in
dhewm3's CMakeLists.txt
I also still had some uncommited changes for that fullscreen workaround
that I'm committing now.
.. that doesn't switch the display resolution, but creates a borderless
fullscreen window at current desktop resolution.
SDL2-only (SDL_WINDOW_FULLSCREEN_DESKTOP).
Doing this with an additional CVar instead of r_fullscreen 2 or similar
has the advantage that it works properly with Alt-Enter
SDL has a bug (at least on Windows) where SDL_CreateWindow() with
SDL_WINDOW_FULLSCREEN doesn't use the configured resolution (if it's
higher than the current desktop resolution).
Try to work around that - based on Yamagi Quake II code.
Also, if GLimp_Init() fails, the "safe mode" fallback is now in
windowed mode instead of fullscreen mode.
Editor also seems to start, didn't test much further.
Only tested 32bit Windows, I fear the editor code isn't 64bit clean..
I hope I haven't broken anything elsewhere..
causes trouble on macOS, and we shouldn't interact with X11 directly
anyway, because SDL does it for us.
OpenBSD apparently needed it (at least it was added for OpenBSD
support), but the only place I can imagine it being needed is the
superfluous #include <SDL_syswm.h> in neo/sys/glimp.cpp - which I now
removed. In case it's needed after all please tell me, then I'll add it
again - but guarded by if(os STREQUALS "OpenBSD") or however one checks
for OpenBSD in CMake.
Commit 9e158470 set the SDL OpenGL attribut SDL_GL_ALPHA_SIZE to 0 since
the alpha channel is used by Wayland. But for X11 the GLX 1.4 specification
clearly states: "If the requested number of bits in attrib_list for a
particular color component is 0 or GLX_DONT_CARE, then the number of
bits for that component is not considered." So if SDL_GL_ALPHA_SIZE is
0 a framebuffer without an alpha channel is created. This is no problem
on the default GLX module due to a non standard implementation but
manifests with Nvidias GLX module. The consequence are render mistakes
like in game display showing static or the flashlight looking weird.
* the OpenAL function definitions mustn't include __declspec(dllimport)
=> fixed by pretending to compile OpenAL statically
* glimp.cpp shouldn't be used in dedicated-only mode (as it was already
the case on Linux and OSX)
=> No special handling for ID_DEDICATED needed in glimp.cpp, as it's not
used anyway
* add APIENTRY to every gl function in stub_gl.cpp for compatibility
with windows headers and MSVC
* remove GL/gl.h #include from win_local.h as it's not needed
* in qgl.h, when building dedicated server for windows, redefine WINGDIAPI
to nothing for SDL_opengl.h #include to get rid off __declspec(dllimport)
by using #pragma push_macro and pop_macro, because our stub is no dll.
Fixes https://github.com/dhewm/dhewm3/issues/39
New CVar "in_kbd" to set the layout for the keyboard. SDL 1.2
doesn't offer any way to determine it, and we need this feature
to use the same key for toggling the console independent of the
keyboard layout.
The old "in_nograb" from the Linux backend is still supported.
Use SDL to set video modes, get a GL context and detect the
amount of VRAM.
As with the Linux GLimp implementation, sys_videoRam can be used
in case the SDL detection fails.
