We have a global GdkGLBackendType now, just set it.
This way, using the variable forces the backend type, and we don't need
special code handling the env vars in the backends.
It also means setting the env var will now "work" on GDK backends that
don't even support that GL backend and simualte another GDK backend
having registered that GL backend already. So you can run
GDK_DEBUG=gl-wgl gtk4-demo
on test what Wayland will do when WGL is in use.
It seems these are sent with `xwindow` set to the root window, so this
was failing to find a surface and get the screen from that.
I'm not sure if there's a reason not to get the screen this way
elsewhere in the function, but it seems this should be correct.
This fixes the behavior of `gdk_x11_display_get_monitors()`, which
wasn't correctly changing when monitors were added or removed. For
instance, this python code was always showing the same number of
monitors when one was turned off and on, but updates correctly with this
change applied:
```python
import gi
gi.require_version("GLib", "2.0")
gi.require_version("Gdk", "4.0")
gi.require_version("Gtk", "4.0")
from gi.repository import GLib, Gdk, Gtk
def f():
print(len(Gdk.Display.get_default().get_monitors()))
return True
GLib.timeout_add_seconds(1, f)
GLib.MainLoop().run()
```
With gtkmm, when using `Application()`, the display is initialized
before we know the application name and therefore, the program class
associated to the display is NULL.
Instead of providing a default value, we set it equal to program name
when NULL. Moreover, we give up on capitalizing the class name to keep
the code super simple. Also, not using a capitalized name is
consistent with `gdk_x11_display_open()`. If someone has a good reason
to use a capitalized name, here is how to do it.
```c
class_hint = XAllocClassHint ();
class_hint->res_name = (char *) g_get_prgname ();
if (display_x11->program_class)
{
class_hint->res_class = (char *) g_strdup (display_x11->program_class);
}
else if (class_hint->res_name && class_hint->res_name[0])
{
class_hint->res_class = (char *) g_strdup (class_hint->res_name);
class_hint->res_class[0] = g_ascii_toupper (class_hint->res_class[0]);
}
XSetClassHint (xdisplay, impl->xid, class_hint);
g_free (class_hint->res_class);
XFree (class_hint);
```
Fix eff53c023a ("x11: set a default value for program_class")
This has the benefit that we can refactor it and make sure we deal with
GdkDisplay::init_gl() not being called at all because
GDK_DEBUG=gl-disable had been specified.
Now that we have the display's context to hook into, we can use it to
construct other GL contexts and don't need a GdkSurface vfunc anymore.
This has the added benefit that backends can have different GdkGLContext
classes on the display and get new GLContexts generated from them, so
we get multiple GL backend support per GDK backend for free.
I originally wanted to make this a vfunc on GdkGLContextClass, but
it turns out all the abckends would just call g_object_new() anyway.
Instead of
Display::make_gl_context_current()
we now have
GLContext::clear_current()
GLContext::make_current()
This fits better with the backends (we can actually implement
clearCurrent on macOS now) and makes it easier to implement different GL
backends for backends (like EGL/GLX on X11).
We also pass a surfaceless boolean to make_current() so the calling code
can decide if a surface needs to be bound or not, because the backends
were all doing whatever, which was very counterproductive.
... or more exactly: Only use paint contexts with
gdk_cairo_draw_from_gl().
Instead of paint contexts being the only contexts who call swapBuffer(),
any context can be used for this, when it's used with
begin_frame()/end_frame().
This removes 2 features:
1. We no longer need a big sharing hierarchy. All contexts are now
shared with gdk_display_get_gl_context().
2. There is no longer a difference between attached and non-attached
contexts. All contexts work the same way.
The vfunc is called to initialize GL and it returns a "base" context
that GDK then uses as the context all others are shared with. So the GL
context share tree now looks like:
+ context from init_gl
- context1
- context2
...
So this is a flat tree now, the complexity is gone.
The only caveat is that backends now need to create a GL context when
initializing GL so some refactoring was needed.
Two new functions have been added:
* gdk_display_prepare_gl()
This is public API and can be used to ensure that GL has been
initialized or if not, retrieve an error to display (or debug-print).
* gdk_display_get_gl_context()
This is a private function to retrieve the base context from
init_gl(). It replaces gdk_surface_get_shared_data_context().
That way, we can give a useful error message when things break down for
users.
These error messages could still be improved in places (like looking at
the actual EGL error codes), but that seemed overkill.
Query the EGL_VISUAL_ID from the egl Config and select a config with the
matching Visual.
This is currently broken on Mesa because it does not expose any RGBA
X Visuals in any EGL config, so we always end up with opaque Windows.
https://gitlab.freedesktop.org/mesa/mesa/-/issues/149
Instead of going via GdkVisual, doing a preselection and letting the GL
initialization improve it, let the GL initialization pick an X Visual
directly using X Visual code directly.
The code should select the same visuals as before as it tries to apply
the same logic, but it's a rewrite, so I expect I messed something up.
We need to initialize GL to select the Visual we are going to use for
all our Windows.
As the Visual needs to be known before we know if we are even gonna use
GL later, we can't avoid initializing it.
Note that this previously happened, too. It was just hidden behind the
GdkScreen initialization.
Instead of the display telling the screen to tell the visuals to tell
the display to initialize itself, just init the display directly.
What a concept.
It's only used during DND to allow use of the root window's cow window
as a DND target, because apparently gnome-shell used to think that was a
great idea to DND to the overview.
Somebody complain to gnome-shell devs about it not being a good idea if
they want it fixed.
Potentially using Wayland is a better idea though.
This reverts 85ae875dcb
Related: https://bugzilla.gnome.org/show_bug.cgi?id=601731
Remove a boatload of "or %NULL" from nullable parameters
and return values. gi-docgen generates suitable text from
the annotation that we don't need to duplicate.
This adds a few missing nullable annotations too.
It was used by all surfaces to track 'is-mapped', but still part of the
GdkToplevelState, and is now replaced with a separate boolean in the
GdkSurface structure.
It also caused issues when a widget was unmapped, and due to that
unmapped a popover which hid its corresponding surface. When this
surface was hidden, it emitted a state change event, which would then go
back into GTK and queue a resize on popover widget, which would travel
back down to the widget that was originally unmapped, causing confusino
when doing future allocations.
To summarize, one should not hide widgets during allocation, and to
avoid this, make this new is-mapped boolean asynchronous when hiding a
surface, meaning the notification event for the changed mapped state
will be emitted in an idle callback. This avoids the above described
reentry issue.
This follows the trail of the Wayland backend in that GdkSurface changes
happen during the layout phase, and that a GDK_CONFIGURE no longer being
used to communicate the size changes of a surface; this now also uses
the layout signal on the GdkSurface.
Reading the comment, it seems to be related being a window manager
decoration utility; this is not something GTK4 aims to handle, just drop
support for this.
Since commit 972134abe4 a frame getting
drawn has three states (with the vendor nvidia driver at least):
1. drawn by gtk waiting on the GPU
2. drawn by GPU waiting on the compositor
3. drawn by compositor
Those three states are encoded in two flags: frame_pending and
frame_still_painting.
frame_pending means step 1 is done, but step 2 and 3 are still
in progress. frame_still_painting means step 2 is still in progress.
After step 1 is finished the surface is frozen until step 3 is finished.
When the compositor notifies gtk it's done with step 3, with a
_NET_WM_FRAME_DRAWN client message, the toolkit thaws the surface to
allow the next frame to proceed.
The compositor sometimes sends gtk a _NET_WM_FRAME_DRAWN client message
between steps 1 and 2. This message should be ignored because it's not
a reply to the current frame.
Unfortunately, gtk currently assumes if it gets a _NET_WM_FRAME_DRAWN
client message while waiting for step 2 that it's actually at step 3,
and proceeds to draw a new frame while the existing frame is still
pending, leading to a blown assertion.
This commit addresses the problem by ignoring _NET_WM_FRAME_DRAWN
client messages from the compositor unless actually expecting one.
Fixes: #2902
