A good portion of geometry handling code was written during the X11
times. The main difference between X11 and Wayland is that kwin doesn't
know where a window will exactly be after resize() or moveResize().
In order to handle Wayland specifics, every window has a bounding
geometry that is being manipulated by move(), resize(), and moveResize().
The frameGeometry(), the clientGeometry(), and the bufferGeometry() are
not manipulated by move(), resize(), and moveResize() directly. Almost
everything that manipulates geometry should use moveResizeGeometry().
This creates a problem though, since the clientGeometry() will be
updated only after the client provides a new buffer, kwin has absolutely
no idea what the client geometry for a given move resize geometry will
be.
Another side of the coin is that decoration updates are performed
asynchronously on wayland, meaning that you cannot use border properties
for anything related to geometry handling and you should avoid using
borderLeft(), borderTop(), borderRight(), and borderBottom() in general.
clientGeometry(), bufferGeometry(), and border*() are good only if you
want to forward an event or render something. They can't be used for
manipulating the geometry.
Unfortunately, AbstractClient::checkWorkspacePosition() needs both,
which is a bit of a problem. To add more oil to the fire, contents
of a decorated window can be snapped to a screen edge. This goes against
the nature of geometry updates on wayland, where we try to indicate
the bounds of the frame geometry and avoid using client and buffer
geometries.
In order to make geometry handling more correct on wayland, this change
removes the ability to snap the contents of a decorated window to a
screen edge. This allows to avoid using the client geometry in
checkWorkspacePosition(), which is a very important function that ensures
the window is inside the workspace.
There is nothing wrong with snapping the frame rather than its contents
and that's what kwin used to do. It was changed with the removal of
"Display borders on maximized windows" option, the relevant commit
didn't provide any reasoning behind the change.
The gravity concept is a generic way to describe how a window must be
positioned during interactive resize. It works both when resizing the
window using a pointer or touch.
This change replaces abort() with Q_ASSERT and Q_UNREACHABLE() macros to
make kwin code base consistent. Besides that, Q_UNREACHABLE may
potentially provide the compiler more info that can be used to generate
more efficient machine code.
While finding this to be benficial when working on the activity
switcher I think it makes sense in general to keep focus on the
current client instead of potentially switching away.
The ifdefs for have_gbm obfuscate the code unnecessarily - the drm backend
is not a great experience with qpainter, so in practice noone should ship
it without gbm anyways.
The Compositor contains nothing that can potentially get dirty and need
repainting.
As is, the advantages of this move aren't really noticeable, but it
makes sense with multiple scenes.
Backend parts are far from ideal, they can be improved later on as we
progress with the scene redesign.
The proprietary NVidia driver now supports gbm, which vastly improves the
user experience. For older devices that will not get gbm support dropping
EglStreams will likely not have a big impact as it has several session breaking
issues anyways.
By removing the backend a lot of logic can be simplified, most notably multi-gpu.
If an output is disconnected, the Workspace will update the
Toplevel.output property for all windows that are on that output, then
it will call AbstractClient::checkWorkspacePosition() to fix window
position.
That may result in some windows partially sticking outside visible area
because AbstractClient::checkWorkspacePosition() has no idea what output
the window was.
This change addresses that problem by delaying updating the
Toplevel.output property so AbstractClient::checkWorkspacePosition()
could pick better window placement.
When geometry updates are blocked, the output doesn't get updated. This
breaks Workspace::clientArea() overload that takes only the window.
Previously, clientArea() would look up the output where the window is
every time it's called, so the fact that the screen id or AbstractOutput
is unsynchronized with the frame geometry was irrelevant.
This change restores the old behavior as 5.23 is affected by the
output() being out of sync with the frameGeometry(). Specifically, when
kwin starts managing an X11 window, it will block geometry updates,
setup the window, e.g. make it fullscreen, and unblock geometry updates.
Since Workspace::clientArea(clientArea, Toplevel) uses the output(),
X11Client::setFullScreen() will most likely put the X11 window at a
wrong output if it's called inside X11Client::manage().
BUG: 443787
On X11, there are four input models. With some input models, it's okay
if the window manager calls XSetInputFocus(), with others, the wm has to
ask the client to make a XSetInputFocus() request.
If kwin wants a client to take input focus, kwin will add the client
to the should_get_focus list, which contains all the windows that
are about to get input focus. Clients are popped from the list upon
receiving FOCUS_IN events.
A client will be added to the should_get_focus list even if kwin thinks
that the client already has input focus because communication between
the wm and xorg is async, anything can happen with input focus in meanwhile.
On the other hand, the wm may sometimes focus the null window if no
window should contain the input focus. The issue is that the
should_get_focus list is not cleaned up in that case, which can lead to
Workspace::mostRecentlyActivatedClient() returning wrong client and
possibly other async related issues.
We don't have such madness on Wayland as the compositor is in charge of
handling input focus.
This change makes Workspace::focusToNull() clear the should_get_focus,
which is reasonable. We need to deactivate "in-flight" focus requests.
This also fixes the bug where fullscreen Wayland windows don't go above
docks and panels due to Workspace::mostRecentlyActivatedClient() returning
bad client.
BUG: 439405
BUG: 395919
This decouples the management of Shadow from the scene window and allows
multiple items share the same Shadow.
Currently, kwin has a single scene graph, but it makes sense to create a
scene graph per output as they could have different layers, etc. This
would also allow QtQuick share more textures with kwin, which is worth
doing for optimization purposes in the future.
Active output is a window management concept. It indicates what output
new windows have to be placed on if they have no output hint. So
Workspace seems to be a better place for it than the Screens class, which
is obsolete.
This allows us to drop obsolete Screens class.
Currently, the Screens class is a thin wrapper around platform outputs +
some extra tracked state, e.g. active output, workspace geometry, etc.
This is a little helper that can be very convenient with our transition
from int-based screen ids to AbstractOutput.
As is, the main issue with int screen ids is that they are extremely
dynamic.
With AbstractOutput being used more heavily, it makes sense to have
something like Screens::number() in the Platform class. As is, the steps
to get an output for a given point are awkward - first, get the screen
id, then use the screen id to get the output.
Currently, the EffectsHandler has two signals that are emitted when the
combined geometry of all outputs change - virtualScreenGeometryChanged()
and screenGeometryChanged(). Having two signals is most likely a
historical artifact.
This change untangles the screenGeometryChanged() signal from the
Workspace and makes it the same as the virtualScreenGeometryChanged()
signal.
The new overloads take the client (as context) and the desired screen id
or a point and return the client area.
The main motivation behind this change is to make the transition to the
new virtual desktop model where a window can be on several desktops less
painful.
This allows changing the type of desk to QVector<VirtualDesktop *>.
Based on the dont_activate flag, Workspace::sendClientToDesktop() will
try to focus the window if it's moved to the current virtual desktop.
In order to implement that, it needs to know whether the window has been
on the current desktop. c->isOnDesktop(desk) is a much sophisticated way
to do that.
If a window is on several desktops, AbstractClient::desktop() will
return the id of the last desktop.
For example, if a window is on virtual desktops A and B, the desktop()
function will return the id of desktop B. This can be the culprit for
bugs such as window snapping not working as expected when moving a
window on virtual desktop A, e.g.
- moved window is on desktops A, and C. desktop() returns the id of C
- snap candidate (l) is on desktops A, and B. desktop() returns the id
of B
Even though the snap candidate window and the moved window are both on
the same desktop (A), the moved window won't be snapped because the
desktop() function returns garbage values.
To fix that, the workspace needs to check whether the window is on the
current desktop.
For what it's worth, that's also how the workspace handles windows being
on multiple activities.
