Commit Graph

87 Commits

Author SHA1 Message Date
Jonas Ådahl
313e3e771c Make meta_* logging utilities not require line break
Unlike g_* logging utilities, the meta_* counterparts behave like odd
printf() functions. Lets change that so they fit better into how logging
is done everywhere else.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1466
2020-10-08 16:38:41 +02:00
Jonas Ådahl
8bdd2aa7db window/wayland: Offset position with size mismatch when resizing
When we resize a window we send it configure requests with size
suggestion. Some clients, e.g. gnome-terminal will limit its size to a
discrete set given the font size resulting in the size often not being
respected completely, but used as a hint to find a size as large as
possible but not larger than the configured size.

When doing an interactive resize dragging the right or top side of a
window, this caused issues with the configured window size not matching
the one used by the client, as the configured position wouldn't be
correct for the actual size. Fix this by offsetting the position given
the size mismatch offset, making the position again in sync with the
size.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1447

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1477
2020-10-07 16:49:35 +02:00
Jonas Ådahl
db7967327a wayland/window: Always flag acked move/resize as 'moved' if moved
We only did this if we weren't currently doing an interactive resize,
but since the finish_move_resize() is not the actual interactive resize
but the acknowledgment of the configure event that was emitted as a
result, we shouldn't limit ourself to the same flags used during resize.

This fixes temporarly "stuck" position of attached modal dialogs while
they are being resized.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1163

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1446
2020-09-18 11:37:23 +00:00
Jonas Dreßler
bc0b9f7628 window: Use pid_t for get_client_pid() vfunc
It makes sense to use pid_t when getting the PID since that will work on
all platforms and architectures.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1180
2020-05-21 23:10:23 +00:00
Jonas Ådahl
ac01e69a67 window-wayland: Don't use grab op for some other window when resizing
When resizing a window interactively, we'll set a grab operation and a
grab window, among other things. If we're resizing (including setting
initial size, i.e. mapping) another window, that didn't change position,
don't use the gravity of the grab operation when resizing our own
window.

This fixes an issue with jumpy popup position when moving a previously
mapped gtk popover.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/999
2020-03-26 17:44:09 +01:00
Jonas Ådahl
fa74da0039 wayland/window: Ignore state changes for popups
We send configure events for state changes e.g. for `appears-focused`,
etc. What we don't want to do is to do this for popup windows, as in
Wayland don't care about this state.

When the focus mode was configured to "sloppy focus" we'd get
`appears-focused` state changes for the popup window only by moving the
mouse cursor around, and while a popup may care about focus, it does not
care about related appearance, as there is no such state in xdg_popup.

What these state changes instead resulted in was absolute window
configuration events, intended for toplevel (xdg_toplevel) windows. In
the end this caused the popup to be positioned aginst at (0, 0) of the
parent window, as the assumptions when the configuration of the popup
was acknowledged is that it had received a relative position window
configuration.

Fix this by simply ignoring any state changes of the window if it is a
popup, meaning we won't send any configuration events intended for
toplevels for state changes. Currently we don't have any way to know
this other than checking whether it has a placement rule. Cleaning up
MetaWindow creation is left to be dealt with another day.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1103

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1122
2020-03-17 21:59:02 +00:00
Jonas Ådahl
6cd0aa429f window: Force placement for first placement rule
If we don't force the placement, we enter the constrain machinery with
the position (0, 0), meaning we always get the "current work area" setup
to correspond to whatever logical monitor was at that position.

Avoid this by doing the same as "meta_window_force_placement()" and set
"window->calc_placement" to TRUE while move-resizing, causing the
move-resize to first calculate the initial position.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1098

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1110
2020-03-06 17:28:09 +01:00
Jonas Ådahl
f97804f4f4 wayland/xdg-shell: Add support for explicit popup repositioning
This commit completes the implementation of `xdg_wm_base` version 3,
which introduces support for synchronized implicit and explicit popup
repositioning.

Explicit repositioning works by the client providing a new
`xdg_positioner` object via a new request `xdg_popup.reposition`. If the
repositioning is done in combination with the parent itself being
reconfigured, the to be committed state of the parent is provided by the
client via the `xdg_positioner` object, using
`xdg_positioner.set__parent_configure`.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
d08a8de265 window: Implement asynchronous popup moving
This commits adds support on the MetaWindow and constraints engine side
for asynchronously repositioning a window with a placement rule, either
due to environmental changes (e.g. parent moved) or explicitly done so
via `meta_window_update_placement_rule()`.

This is so far unused, as placement rules where this functionality is
triggered are not yet constructed by the xdg-shell implementation, and
no users of `meta_window_update_placement_rule()` exists yet.

To summarize, it works by making it possible to produce placement rules
with the parent rectangle a window should be placed against, while
creating a pending configuration that is not applied until acknowledged
by the client using the xdg-shell configure/ack_configure mechanisms.

An "temporary" constrain result is added to deal with situations
where the client window *must* move immediately even though it has not yet
acknowledged a new configuration that was sent. This happens for example
when the parent window is moved, causing the popup window to change its
relative position e.g. because it ended up partially off-screen. In this
situation, the temporary position corresponds to the result of the
movement of the parent, while the pending (asynchronously configured)
position is the relative one given the new constraining result.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
6c82feb1b8 wayland/window-configuration: Track resize flags and gravity too
Will later be used to determine in what way a pending configuration will
resize.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
0dac91cffc Add MetaGravity and replace X11 equivalent with it
MetaGravity is an enum, where the values match the X11 macros used for
gravity, with the exception that `ForgetGravity` was renamed
`META_GRAVITY_NONE` to have less of a obscure name.

The motivation for this is to rely less on libX11 data types and macros
in generic code.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
ff381d1d52 constraints: Pass constrained relative coordinates to window impl
A placement rule placed window positions itself relative to its parent,
thus converting between relative coordinates to absolute coordinates,
then back to relative coordinates implies unwanted restrictions for
example when the absolute coordinate should not be calculated againts
the current parent window position.

Deal with this by keeping track of the relative position all the way
from the constraining engine to the move-resize window implementation.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
05e9d6ab9e window: Put placement related fields in a anynomous struct
To organize things a bit better, put the fields related to the placement
rule state in its own anonymous struct inside MetaWindow. While at it,
rename the somewhat oddly named variable that in practice means the
current relative window position.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
d22f947bf5 wayland/window: Pass popup configuration using relative coordinates
After popup placement rules have gone through the constraints engine has
ended up resulting in an actual move, pass the window configuration down
the path using relative coordinates, as that is what the next layer
(xdg-shell implementation) actually cares about.

In the future, this will also be helpful when the configured position is
not against the current state of the parent.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Jonas Ådahl
7f9fac2ba2 window/wayland: Don't inhibit finishing moves if any window is resized
meta_window_wayland_finish_move_resize() inhibited window moves to be
finished if there was a resize grab active at the time, in order to
handle window resizing. Change this to only affect the grabbed window
itself, so that e.g. a popup can be positioned according to a pending
configuration while there is an active resize grab.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/705
2020-02-29 21:01:50 +00:00
Sebastian Keller
51733ca499 window/wayland: Plug window configuration leak
The acked configuration is removed from the pending configuration list
by acquire_acked_configuration(), but finish_move_resize() does not free
the data after applying the configuration.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1020
2020-01-24 21:10:11 +00:00
Jonas Ådahl
554644f9e0 wayland: Rework asynchronous window configuration
This changes how asynchronous window configuration works. Prior to this
commit, it worked by MetaWindowWayland remembering the last
configuration it sent, then when the Wayland client got back to it, it
tried to figure out whether it was a acknowledgment of the configuration
or not, and finish the move. This failed if the client had acknowledged
a configuration older than the last one sent, and it had hacks to
somewhat deal with wl_shell's lack of configuration serial numbers.

This commits scraps that and makes the MetaWindowWayland take ownership
of sent configurations, including generating serial numbers. The
wl_shell implementation is changed to emulate serial numbers (assuming
each commit acknowledges the last sent configure event). Each
configuration sent to the client is kept around until the client one. At
this point, the position used for that particular configuration is used
when applying the acknowledged state, meaning cases where we have
already sent a new configuration when the client acknowledges a previous
one, we'll still use the correct position for the window.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
2019-12-09 10:09:40 +01:00
Jonas Ådahl
4bacb3621b window/wayland: Make .._wayland_move_resize() name more explanatory
The intention of meta_window_wayland_move_resize() is to finish a
move-resize requested previously, e.g. by a state change, or a
interactive resize. Make the function name carry this intention, by
renaming it to meta_window_wayland_finish_move_resize().

https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
2019-12-09 10:09:40 +01:00
Florian Müllner
c843102eec stack: Delegate layer calculation to a window vfunc
While most of the code to compute a window's layer isn't explicitly
windowing backend specific, it is in practice: On wayland there are
no DESKTOP windows(*), docks(*) or groups.

Reflect that by introducing a calculate_layer() vfunc that computes
(and sets) a window's layer.

(*) they shall burn in hell, amen!

https://gitlab.gnome.org/GNOME/mutter/merge_requests/949
2019-11-29 15:14:38 +01:00
Georges Basile Stavracas Neto
fb9e8768a3 window-actor: Handle geometry scale
Geometry scale is applied to each surface individually, using
Clutter scales, and not only this breaks subsurfaces, it also
pollutes the toolkit and makes the actor tree slightly too
fragile. If GNOME Shell mistakenly tries to set the actor scale
of any of these surfaces, for example, various artifacts might
happen.

Move geometry scale handling to MetaWindowActor. It is applied
as a child transform operation, so that the Clutter-managed
scale properties are left untouched.

In the future where the entirety of the window is managed by a
ClutterContent itself, the geometry scale will be applied
directly into the transform matrix of MetaWindowActor. However,
doing that now would break the various ClutterClones used by
GNOME Shell, so the child transform is an acceptable compromise
during this transition.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
2019-08-23 13:23:07 +00:00
Jonas Ådahl
59bf1f4838 window/wayland: Don't always use constrained size when unfullscreening
When we're unfullscreening, we might be returning to a window state that
has its size either managed by constraints (tiled, maximized), or not
(floating). Lets just pass the configure size 0x0 when we're not using
constrained sizes (i.e. the window going from being fullscreen to not
maximized) and let the application decide how to size itself.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/638

https://gitlab.gnome.org/GNOME/mutter/merge_requests/621
2019-06-13 16:40:57 +00:00
Jonas Ådahl
425611eadf window/wayland: Use constrained size when unmaximizing while fullscreen
Otherwise we'll ask the client to use the size 0x0 with the fullscreen
state set.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/621
2019-06-13 16:40:57 +00:00
Carlos Garnacho
ea9d8a895b wayland: Drop error trap
Code underneath seems to handle errors properly, or be x11-agnostic
entirely, this is apparently here to save a few XSync()s on X11. Just
drop this windowing dependent bit to make things cleaner.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/420
2019-05-24 15:30:31 +00:00
Carlos Garnacho
86de79cfc5 core: Untangle input focus management
In all places (including src/wayland) we tap into meta_x11_display* focus
API, which then calls meta_display* API. This relation is backwards, so
rework input focus management so it's the other way around.

We now have high-level meta_display_(un)set_input_focus functions, which
perform the backend-independent maintenance, and calls into the X11
functions where relevant. These functions are what callers should use.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/420
2019-05-24 15:30:31 +00:00
Carlos Garnacho
5e0523cc8b x11: Move X11 calls to map/unmap a MetaWindow to MetaWindowX11
Add 2 vmethods so that MetaWindowX11 may handle the X11 calls itself.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/420
2019-05-24 15:30:31 +00:00
Marco Trevisan (Treviño)
f798912cbd window: Move can_ping to a function and implement in X11
https://gitlab.gnome.org/GNOME/mutter/merge_requests/421
2019-02-13 02:07:41 +00:00
Marco Trevisan (Treviño)
43633d6b2f window: Add is_focusable class method
Implement is_focusable for both x11 and wayland and just use this check
so that we can abstract things more and be less dependent on window backend.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/421
2019-02-13 02:07:41 +00:00
Jonas Ådahl
2f4a68c8c3 Clean up include macros mess
The order and way include macros were structured was chaotic, with no
real common thread between files. Try to tidy up the mess with some
common scheme, to make things look less messy.
2018-11-06 17:17:36 +01:00
Jonas Ådahl
7d82cdeea3 window/wayland: Freeze updates until shown
Not until the window is shown do we know what monitor it's on, thus the
size, so freeze updates (shape etc) until the window is shown.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/229
2018-09-19 15:39:54 +00:00
Jonas Ådahl
e2e7296612 window: Move out 'updates frozen' state into implementations
Implementation of said state was just related to X11, so move it into
window-x11.c. The Wayland path always fell back on the returning TRUE,
so just do that for now.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/229
2018-09-19 15:39:54 +00:00
Jonas Ådahl
e191c21e04 window/wayland: Don't recursive indefinitely when updating monitor
When we update the main monitor, there is a rule that makes it so that
popup windows use the same main monitor as their parent. In the commit
f4d07caa38 the call that updates and
fetches the main monitor of the toplevel accidentally changed to update
from itself, causing a indefinite recursion eventually resulting in a
crash.

Closes: https://gitlab.gnome.org/GNOME/mutter/issues/279
2018-08-27 17:49:52 +02:00
Jonas Ådahl
8d3e053059 window: Force update monitor on hot plugs
Commit a3da4b8d5b changed updating of
window monitors to always use take affect when it was done from a
non-user operation. This could cause feed back loops when a non-user
driven operation would trigger the changing of a monitor, which itself
would trigger changing of the monitor again due to a window scale
change.

The reason for the change, was that when the window monitor changed due
to a hot plug, if it didn't actually change, eventually the window
monitor pointer would be pointing to freed memory.

Instead of force updating the monitor on all non-user operations, just
do it on hot plugs. This allows for the feedback loop preventing logic
to still do what its supposed to do, without risking dangling pointers
on hot plugs.

Related: https://gitlab.gnome.org/GNOME/mutter/issues/189
Closes: https://gitlab.gnome.org/GNOME/mutter/issues/192
2018-08-27 08:33:00 +00:00
Jonas Ådahl
f4d07caa38 window: Pass flag to meta_window_update_monitor() instead of bool
The bool determines whether the call was directly from a user operation
or not. To add more state into the call without having to add more
boolenas, change the boolean to a flag (so far with 'none' and 'user-op'
as possible values). No functional changes were made.

https://gitlab.gnome.org/GNOME/mutter/issues/192
2018-08-27 08:33:00 +00:00
Olivier Fourdan
a3da4b8d5b window/wayland: Always update monitor for non-user ops
meta_window_wayland_update_main_monitor() would skip the monitor update
if the difference in scale between the old and the new monitor would
cause another monitor change.

While this is suitable when the monitor change results from a user
interactively moving the surface between monitors of different scales,
this can leave dangling pointers to freed monitors when this is
triggered by a change of monitor configuration.

Make sure we update the monitor unconditionally if not from a user
operation.

Closes: https://gitlab.gnome.org/GNOME/mutter/issues/189
2018-07-24 10:44:49 +02:00
Armin Krezović
390314adfb Rename errors.[ch] to meta-x11-errors.[ch]
Also rename meta_error_trap_* to meta_x11_error_trap_* and
move meta-x11-errors.c to src/x11

https://bugzilla.gnome.org/show_bug.cgi?id=759538
2018-07-06 19:47:17 +02:00
Armin Krezović
1d5e37050d Stop using MetaScreen where it is unnecessary
https://bugzilla.gnome.org/show_bug.cgi?id=759538
2018-07-06 19:47:16 +02:00
Armin Krezović
05899596d1 Move X11 helper windows and xprops to MetaX11Display
https://bugzilla.gnome.org/show_bug.cgi?id=759538
2018-07-06 19:47:16 +02:00
Armin Krezović
98d912ba5f Move stack tracking and guard_window outside of MetaScreen
Move stack, stack_tracker to MetaDisplay guard_window to MetaX11Display

https://bugzilla.gnome.org/show_bug.cgi?id=759538
2018-07-06 19:47:16 +02:00
Armin Krezović
dacc041d0c Switch meta_error_trap functions to MetaX11Display
They are X11 specific functions, used for X11 code. They have been
improved per jadahl's suggestion to use gdk_x11_lookup_xdisplay and
gdk_x11_display_error_trap_* functions, instead of current code.

https://bugzilla.gnome.org/show_bug.cgi?id=759538
2018-07-06 19:47:16 +02:00
Georges Basile Stavracas Neto
762a3f89a9 wayland: Add function to query if window needs move or resize
This will be used by the next commit to determine when a window
geometry change should be ignored or not. Normally, it would be
enough to just check if the position and sizes changed.

The position, in this case, is relative to the client buffer, not
the global position. But because it is not global, there is one,
admitedly unlikely, situation where the window state is updated
while the client size and relative positions don't change.

One can trigger this by e.g. tiling the window to the half-left of
the monitor, then immediately tile it to half-right. In this case,
the window didn't change, just it's state, but nonetheless we need
to notify the compositor and run the full move/resize routines.

When that case happens, though, the MetaWindowWayland is tracking
the pending state change or a move. And this is what we need to
expose.

https://bugzilla.gnome.org/show_bug.cgi?id=780292
Issue: #78
2018-04-25 21:55:05 -03:00
Georges Basile Stavracas Neto
822c2666f5 window: Let implementations finish state changes
In the old, synchronous X.org world, we could assume that
a state change always meant a synchronizing the window
geometry right after. After firing an operation that
would change the window state, such as maximizing or
tiling the window,

With Wayland, however, this is not valid anymore, since
Wayland is asynchronous. In this scenario, we call
meta_window_move_resize_internal() twice: when the user
executes an state-changing operation, and when the server
ACKs this operation. This breaks the previous assumptions,
and as a consequence, it breaks the GNOME Shell animations
in Wayland.

The solution is giving the MetaWindow control over the time
when the window geometry is synchronized with the compositor.
That is done by introducing a new result flag. Wayland asks
for a compositor sync after receiving an ACK from the server,
while X11 asks for it right away.

Fixes #78
2018-04-25 21:55:05 -03:00
Jonas Ådahl
44624736c5 wayland: Push actor state instead of itself pulling
Make the Wayland objects push the state relevant to their role to the
MetaSurfaceActor instead of MetaSurfaceActorWayland pulling the state
from the associated surface.

This makes the relationship between the actor and the objects that
constructs it more clear; the actor is a drawable that the protocol
objects control, not the other way around.

This will make it easier to "detach" a surface actor from a surface,
which is necessary when unmapping a window while the underlying surface
is yet to be destroyed and potentially reused.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/5
https://bugzilla.gnome.org/show_bug.cgi?id=791938
2018-02-23 18:57:47 +08:00
Olivier Fourdan
5f05112b9a wayland: update location prior to maximize
When maximizing a window, the previous location is saved so that
un-maximize would restore the same original window location.

However, if a Wayland client starts with a window maximized, the
previous location will be 0x0, so if we have to force placement in
xdg_toplevel_set_maximized(), we should update the location as well so
that the window is placed on the right monitor when un-maximizing.

For that purpose, add a new flag to force the update of the window
location, and use that flag from xdg_toplevel_set_maximized().

https://bugzilla.gnome.org/show_bug.cgi?id=783901
2018-01-11 11:03:04 +01:00
Olivier Fourdan
6cf7d2d47f wayland: Do not enforce a size on un-maximize
When un-maximizing, use a zero size to pass to the client so that it can
use the right un-maximized size that fits.

https://bugzilla.gnome.org/show_bug.cgi?id=783901
2018-01-11 11:03:04 +01:00
Olivier Fourdan
bd9a300801 window: Defer stack placement without a buffer
When closing a window and showing a new one, the new one may not be
granted input focus until it gets a buffer on Wayland.

If another window is chosen to receive focus and raised on top of stack,
the newly mapped window is focused but placed underneath that other
window.

Meaning that for Wayland surfaces, we need to defer adding the window to
the stack until we actually get to show it, once we have a buffer
attached.

Rather that checking the windowing backend prior to decide if a window
is stackable or not, introduce a new vfunc is_stackable() which tells
if a window should be added to the stack regardless of the underlying
windowing system.

Also add meta_window_is_in_stack() API rather than checking the stack
position directly (replacing the define WINDOW_IN_STACK only available
in stack.c) and remove a window from the stack only if it is present
in the stack, so that the test in meta_stack_remote() becomes
irrelevant.

https://bugzilla.gnome.org/show_bug.cgi?id=780820
2018-01-11 11:03:04 +01:00
Jonas Ådahl
0add6f62b6 window/wayland: Handle resizing when headless
We tried to get the geometry scale, which may depend on the main
logical monitor assigned to the window. To avoid dereferencing a NULL
logical monitor when headless, instead assume the geometry scale is 1.

https://bugzilla.gnome.org/show_bug.cgi?id=788764
2017-11-10 10:24:10 +08:00
Jonas Ådahl
2df4ccd1cd window: Handle being headless better
This avoids updating state (such as position, size etc) when going
headless. Eventually, when non-headless, things will be updated again,
and not until then will we be able to update to a valid state.

https://bugzilla.gnome.org/show_bug.cgi?id=730551
2017-08-30 13:44:05 +08:00
Olivier Fourdan
dd12f569d9 wayland: add inhibit shortcut mechanism
Add a mechanism to MetaWaylandSurface that inhibits compositor's own
shortcuts when the surface has input focus, so that clients can receive
all key events regardless of the compositor own shortcuts.

This will help with implementing "fake" active grabs in Wayland and
XWayland clients.

https://bugzilla.gnome.org/show_bug.cgi?id=783342
2017-08-02 11:58:55 +02:00
Jonas Ådahl
4afa66fe41 wayland/window: Update toplevel main monitor before non-toplevel
When updating the main monitor, make sure to update the toplevel main
monitor before trying to use that as the main monitor for non-toplevel
windows (such as popups). Without this, when the main monitor is
updated as a side effect to monitors being changed (for example due to
a hot plug event, or coming back from being suspended) the
main monitor pointer may, after 'monitors-changed' has completed, point to
freed memory resulting in undefined behaviour.

https://bugzilla.gnome.org/show_bug.cgi?id=784867
2017-07-17 09:59:34 +08:00
Jonas Ådahl
b64c69e4bc logical-monitor: Make scale a float
To support fractional scaling, the logical monitor scale must be stored
as a float. No other functional changes is part of this commit.

https://bugzilla.gnome.org/show_bug.cgi?id=765011
2017-07-14 20:54:26 +08:00