Commit Graph

26135 Commits

Author SHA1 Message Date
Georges Basile Stavracas Neto
fed5f4d9aa window-actor: Inhibit culling when blitting to screencast
This allows us to screencast any window continuously, even
without it being visible. Because it's still being painted,
clients continue to receive frame callbacks, and people
are happy again.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:58 +00:00
Georges Basile Stavracas Neto
73250b8f4c clutter/actor: Add culling inhibiting API
This will allow us to continue painting actors that are
outside the visible boundaries of the stage view.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:58 +00:00
Georges Basile Stavracas Neto
f6700f19a7 window-stream-src: Finish framebuffer after blitting
Just like what's done for monitor screencasting. Unfortunately, there's
no mechanism to share fences with PipeWire clients yet, which forces
us to guarantee that a frame is completed after blitting.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:58 +00:00
Georges Basile Stavracas Neto
ea34915df3 window-stream-src: Implement cursor blitting
A regression compared to the old code, we're not drawing the cursor
when on EMBEDDED mode.

Blit the cursor to the screencast framebuffer when on EMBEDDED mode.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:58 +00:00
Georges Basile Stavracas Neto
37742c5cde window-stream-src: Ensure initial frame is recorded
MetaScreenCastWindowStreamSrc connects to the "damaged" signal of
MetaWindowActor. This signal is not exactly tied to the paint cycle
of the stage, and a damage may take quite a while to arrive when
a client doesn't want to draw anything. For that reason, the window
screencast can start empty, waiting for a damage to arrive.

Ensure at least one frame is recorded when enabling the window stream.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1097

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:57 +00:00
Georges Basile Stavracas Neto
cdd27d0e53 window-actor: Clip before translate when blitting
cogl_framebuffer_push_rectangle_clip() acts on the current modelview
matrix. That means the result of clipping then translating will be
different of the result of translating then clipping.

What we want for window screencasting is the former, not the latter.
Move the translation code (and associated) to after clipping.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1097

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:57 +00:00
Georges Basile Stavracas Neto
82778f72a4 window-actor: Shuffle some lines around
Move the CoglColor assignment right above the cogl_framebuffer_clear() call,
and let these wonderful partners together to delight us with an easier to
read code.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1129
2020-03-27 23:29:57 +00:00
Carlos Garnacho
d846fabda2 cogl-pango: Forward alpha from correct color
Use the override color alpha, if set.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1155
2020-03-27 23:33:38 +01:00
Carlos Garnacho
2d94a34a14 cogl-pango: Honor foreground alpha PangoAttribute
Instead of hardcoding 0xff as alpha, forward this attribute.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1155
2020-03-27 23:33:35 +01:00
Jonas Dreßler
92710d8f89 clutter/stage-cogl: Check for buffer age early
Fix a regression that got introduced with
c483b52d24 where we started passing the
redraw_clip to paint_stage() instead of creating a temporary view_region
for unclipped redraws: In case we detect an invalid buffer age, we fall
back to doing an unclipped redraw after we passed the first check
setting up may_use_clipped_redraw. That means we didn't reset the
redraw_clip to the view_rect, and we're now going to redraw the stage
using the original redraw clip even though we're swapping the full
framebuffer without damage.

To fix that, check for the buffer age before setting up the
fb_clip_region and the redraw_clip and set may_use_clipped_redraw to
FALSE if the buffer age is invalid, too. This ensures the redraw_clip is
always going to be correctly set to the view rect when we want to force
a full redraw.

Fixes https://gitlab.gnome.org/GNOME/mutter/issues/1128
2020-03-27 16:37:45 +00:00
Hans de Goede
da600b8400 cursor-renderer-native: Take panel-orientation into account for sprite transform
When calculating the transform we should apply to the cursor sprite
before uploading it to the cursor plane, we must also take into
account non upright mounted LCD panels.

Otherwise the cursor ends up 90 degrees rotated on devices where the
LCD panel is mounted 90 degrees rotated in its enclosure.

This commit fixes this by calling meta_monitor_logical_to_crtc_transform
in get_common_crtc_sprite_transform_for_logical_monitors to adjust the
transform for each Monitor in the LogicalMonitor.

Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1123

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1153
2020-03-27 15:10:35 +00:00
Robert Mader
6aa546145f core: Demote tiff and bmp image formats in the clipboard manager
Support for them appears to be way less common than e.g. png, which is
currently the preferred format from Firefox, Chromium, Libreoffice and others.
Adopt to that fact.

As a side effect, this works around a bug observed when copying images in
Firefox on Wayland.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1141
2020-03-27 14:37:29 +00:00
Georges Basile Stavracas Neto
3956ffd5e8 cogl/driver: Remove GError from context_init
It is not used by anyone, let's just remove it.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1152
2020-03-27 09:01:43 -03:00
Georges Basile Stavracas Neto
05341221d4 cogl/renderer: Remove documentation of nonexistent enum
We don't want to delve into the philosohical study of the not-being,
so let's just not document an enum value that doesn't exist anymore.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1151
2020-03-26 18:44:13 -03:00
Georges Basile Stavracas Neto
95642d05a6 cogl/gl: Move shared functions to shared file
Cogl shares some GL functions between the GLES and the big
GL drivers. Namely, it shares _cogl_driver_gl_context_init
and _cogl_driver_gl_context_deinit between these two drivers.

The plot twist is: even though these functions are shared and
their prototypes are in cogl-util-gl-private.h, they're actually
implemented inside cogl-driver-gl.c, which is strictly only
about the big GL driver.

This is problematic when building Mutter on ARM v7, where we
need to disable OpenGL, but keep GLES enabled.

Fix this by moving the shared GL functions to a shared GL file.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1151
2020-03-26 18:43:32 -03:00
Georges Basile Stavracas Neto
51cd8aed96 ci: Add a new 'build-without-opengl-and-glx' step
To make sure we don't regress with this specific set of flags.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1151
2020-03-26 18:24:54 -03:00
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
a68e6972a2 cursor-renderer-native: Set cursor hotspot metadata on plane assignment
This triggers the paths in the legacy KMS backend to use
drmModeSetCursor2(), making virtual machines using "seamless mouse mode"
behave correctly again.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1094

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1136
2020-03-26 16:18:28 +00:00
Jonas Ådahl
55cf1c1496 kms/plane-assignment: Add API to set cursor hotspot metadata
The transactional KMS API has been modelled after atomic KMS. Atomic KMS
currently doesn't support forwarding cursor hotspot metadata, thus it
was left out of the transactional KMS API having the user set the simply
create a plane assigment with the cursor sprite assigned to a cursor
plane using regular coordinates.

This, however, proved to be inadequate for virtual machines using
"seamless mouse mode" where they rely on the cursor position to
correspond to the actual cursor position of the virtual machine, not the
cursor plane. In effect, this caused cursor positions to look "shifted".

Fix this by adding back the hotspot metadata, right now as a optional
field to the plane assignment. In the legacy KMS implementation, this is
translated into drmModeSetCursor2() just as before, while still falling
back to drmModeSetCursor() with the plane coordinates, if either there
was no hotspot set, or if drmModeSetCursor2() failed.

Eventually, the atomic KMS API will learn about hotspots, but when
adding our own atomic KMS backend to the transacitonal KMS API, we must
until then still fall back to legacy KMS for virtual machines.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1136
2020-03-26 16:18:28 +00:00
Jonas Ådahl
343de21af5 monitor-transform: Add API to transform point
Transforms a point in a rectangle with the origin (0, 0). To be used to
transform cursor hotspots within a cursor sprite.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1136
2020-03-26 16:18:28 +00:00
Jonas Ådahl
3c157242fa cursor-sprite: Add API to get dimension
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1136
2020-03-26 16:18:28 +00:00
Jonas Ådahl
32c99513c8 clutter/actor: Inherit cloned painting when calculating resource scale
When calculating the resource scale of a clone source, we might end up
in situations where we fail to do so, even though we're in a paint. A
real world example when this may happen if this happens:

 * A client creates a toplevel window
 * A client creates a modal dialog for said toplevel window
 * Said client commits a buffer to the modal before the toplevel

If GNOME Shell is in overview mode, the window group is hidden, and the
toplevel window actor is hidden. When the clone tries to paint, it fails
to calculate the resource scale, as the parent of the parent (window
group) is not currently mapped. It would have succeeded if only the
clone source was unmapped, as it deals with the unmapped actor painting
by setting intermediate state while painting, but this does not work
when the *parent* of the source is unmapped as well.

Fix this by inheriting the unmapped clone paint even when calculating
the resource scale.

This also adds a test case that mimics the sequence of events otherwise
triggered by a client. We can't add a Wayland client to test this, where
we actually crash is in the offscreen redirect effect used by the window
dimming feature in GNOME Shell.

Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/808

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1147
2020-03-26 11:42:23 +01:00
Jonas Ådahl
40c345d6f3 cursor-sprite-xcursor: Emulate Wayland hotspot limitations
For HiDPI pointer cursors backed by Wayland surfaces, the hotspot must
be placed using integers on the logical pixel grid. In practice what
this means is that if the client loads a cursor sprite with the buffer
scale 2, and it's hotspot is not dividable by 2, it will be rounded
down to an integer that can. E.g. a wl_surface with buffer scale 2 and a
cursor image with hotspot coordinate (7, 7) will have the coordinate
(3.5, 3.5) in surface coordinate space, and will in practice be rounded
down to (3, 3) as the hotspot position in wl_pointer only takes
integers.

To not potentially shift by 1 pixel on HiDPI monitors when switching
between wl_surface backend cursor sprites and built-in ones, make the
built in one emulate the restrictions put up by the Wayland protocol.

This also initializes the theme scale of the xcursor sprite instances to
1, as they may not have been set prior to being used, it'll only happen
in response to "prepare-at" signals being emitted prior to rendering.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/1092

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1107
2020-03-26 08:47:37 +00:00
Jonas Ådahl
8beef8ccd0 shaped-texture: Fix use-nearest check when viewports are scaled
We checked that the content size was appropriately painted in the stage,
but didn't take into account that the size of the sampled texture
region, meaning that when stage views were scaled, we'd think that we
would draw a texture scaled, as e.g. a 200x200 sized texture with buffer
scale 2 would have the size 100x100. When stage views were not scaled,
we'd apply a geometry scale meaning it'd end up as 200x200 anyway, thus
pass the check, but when stage views are scaled, it'd still be painted
as a 100x100 shaped texture on the stage, thus failing the
are-we-unscaled test.

Fix this by comparing the transformed paint size with the sampled size,
instead of the paint size again, when checking whether we are being
painted scaled or not. For example, when stage views are scaled, our
200x200 buffer with buffer scale 2, thus content size 100x100 will
transform to a 200x200 paint command, thus passing the test. For
non-scaled stage views, our 200x200 buffer with buffer scale 2 thus
content size 100x100 will also transform into a 200x200 paint command,
and will also pass the check, as the texture sample region is still
200x200.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/804

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1124
2020-03-26 08:32:46 +00:00
Jonas Ådahl
62d0dd907b clutter-utils: Fix a couple of coding style issues
Multiple assignments on the same line were split up, so was a super long
line.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1124
2020-03-26 08:32:46 +00:00
Jonas Ådahl
0462208d4e crtc-xrandr: Respect configured RANDR panning
A user may have configured an output to be panning, e.g. using xrandr
--output <output> --mode <mode> --panning <size>. Respect this by making
the logical monitor use the panning size, instead of the mode. This
makes e.g. makes the background cover the whole panning size, and panels
etc will cover the whole top of the panned area, instead of just the top
left part covering the monitor if having panned to (0, 0).

No support is added to configuring panning, i.e. a panned monitor
configuration cannot be stored in monitors.xml.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1085
2020-03-26 09:24:25 +01:00
Jonas Ådahl
6885c37784 cogl: Mark exported cogl symbols using COGL_EXPORT
Just like libmutter-clutter, and libmutter, mark exported symbols with
an COGL_EXPORT macro. This removes the .map and .map.in files previously
used, containing a list of semi private symbols. This symbol was out of
date, i.e. pointed to non-existing symbols, and was also replaced with
COGL_EXPORT macros.

unit_test_* symbols are exported by the help of the unit test defining
macro. test_* symbols are no longer supported as it proved unnecessary.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1059
2020-03-26 09:05:38 +01:00
Jonas Ådahl
238e41d493 cogl: Install cogl-trace.h and include from cogl.h
This is so that cogl-trace.h can start using things from cogl-macros.h,
and so that it doesn't leak cogl-config.h into the world, while exposing
it to e.g. gnome-shell so that it can make use of it as well. There is
no practical reason why we shouldn't just include cogl-trace.h via
cogl.h as we do with everything else.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1059
2020-03-26 09:05:38 +01:00
Carlos Garnacho
8699482475 backends: Check both input settings and mapper for tablet monitors
The upper layers (OSDs basically) want to know the monitor that a
tablet is currently assigned to, not the monitor just as configured
through settings.

This broke proper OSD positioning for display-attached tablets since
commit 87858a4e01, as the MetaInputMapper kicks in precisely when
there is no configured monitor for the given device.

Consulting both about the assigned output will make OSDs pop up
again in the right place.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/971
2020-03-25 19:09:32 +00:00
Carlos Garnacho
dcaa45fc0c backends/x11: Implement is_grouped for X11
If the devices have a wacom description, compare those. Otherwise,
look up the devices' VID:PID, if they match they should also be
grouped.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/971
2020-03-25 19:09:32 +00:00
Carlos Garnacho
3c4f5ddcb4 core: Let pad mode switch events always go through MetaInputSettings
We used to inhibit all pad actions while the OSD is shown, but one we
would actually want to handle are mode switches while the OSD is open.
So it has an opportunity to catch up to the mode switch.

This lets MetaInputSettings reflect the mode switch (eg. when querying
action labels), so the OSD has an opportunity to update the current
actions.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/975
2020-03-25 19:56:09 +01:00
Carlos Garnacho
3aece84499 cogl-pango: Make color glyphs unaffected by foreground color
Making color glyphs affected by the foreground color makes them become
"tinted" on any other color than white. Make it sure we always paint
those white by checking the cached glyph value, the foreground color
will be reset on the next iteration through glyphs.

https://gitlab.gnome.org/GNOME/gnome-shell/issues/850

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1148
2020-03-25 11:14:33 +00:00
Carlos Garnacho
40fb06ca17 cogl-pango: Cache whether glyphs are backed up by a color font
This will be necessary later on.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1148
2020-03-25 11:14:33 +00:00
Florian Müllner
d4c070da88 window: Really propagate effective on-all-workspaces setting to transients
Commit cda9579034 fixed a corner case when setting the initial workspace
state of transient windows, but it still missed a case:

should_be_on_all_workspaces() returns whether the window should be on all
workspaces according to its properties/placement, but it doesn't take
transient relations into account.

That means in case of nested transients, we can still fail the assert:

 1. on-all-workspaces toplevel
 2. should_be_on_all_workspaces() is TRUE for the first transient's parent,
    as the window from (1) has on_all_workspaces_requested == TRUE
 3. should_be_on_all_workspaces() is FALSE for the second transient's
    parent, as the window from (2) is only on-all-workspace because
    of its parent

We can fix this by either using the state from the root ancestor
instead of the direct transient parent, or by using the parent's
on_all_workspaces_state.

The latter is simpler, so go with that.

https://gitlab.gnome.org/GNOME/mutter/issues/1083
2020-03-24 18:15:33 +00:00
Carlos Garnacho
d052f9c070 backends: Drop internal WacomDevice in MetaInputSettings
Use the one from MetaInputDevice instead. Since we no longer try
to ask for WacomDevices that weren't first retrieved:

Closes: https://gitlab.gnome.org/GNOME/mutter/issues/1086

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1109
2020-03-24 18:07:31 +00:00
Carlos Garnacho
3b88af94e3 backends/x11: Drop internal WacomDevice lookups
Just use the ones from MetaInputDevice.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1109
2020-03-24 18:07:31 +00:00
Carlos Garnacho
1f00aba92c backends: Add MetaInputDevice derivable class
This class sits between ClutterInputDevice and the backend implementations,
it will be the despositary of features we need across both backends, but
don't need to offer through Clutter's API.

As a first thing to have there, add a getter for a WacomDevice. This is
something scattered across and somewhat inconsistent (eg. different places
of the code create wacom devices for different device types). Just make it
here for all devices, so users can pick.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1109
2020-03-24 18:07:31 +00:00
Carlos Garnacho
ec1195e3ff backends: Fix configuration changes to tap[-and-drag]
Most people just see a harmless warning when applying this setting to
all touchpads (which this patch fixes). But tap[-and-drag] is supposed
to remain enabled for display-less Wacom tablets, despite configuration
changes.

Fix this by using the mapping function, so the setting is forced on for
wacom devices. This happens on a per-device basis, so the warning is
gone too.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1145
2020-03-24 17:05:12 +00:00
Carlos Garnacho
18b661cc93 backends: Add mapping function arg to settings_set_bool_setting()
This will be useful to actually determine on a per-device basis the
setting being applied, while still doing changes on a per-device-type
basis.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1145
2020-03-24 17:05:12 +00:00
Carlos Garnacho
8592a8591b wayland: Handle NULL preedit text
The preedit text may be NULL (eg. when unsetting it). This started
causing crashes since commit db9b60cc63, duh.

Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1132
2020-03-24 16:07:44 +00:00
Peter Hutterer
7fa7c2aeb7 backends: use the enum name instead of a literal 0
No functional change.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1144
2020-03-24 15:46:43 +10:00
Robert Mader
41130b08eb surface-actor: Add culling offset for geometry scale
This fixes a case that was overlooked in
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1036 - when we
have a geometry scale > 1 and Wayland subsurfaces that have an offset
to their parent surface (which is often the case when the toplevel surface
includes decoration/shadows etc.), we have to add extra offset to their
opaque regions so they match their 'visible' location.

This is necessary as `meta_cullable_cull_out_children` moves the coordinate
system during culling, but does not know about geometry scale.

Also, remove the redundant check for `window_actor` - we only hit this code
path if a `window_actor` culls out its children.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1108
2020-03-23 20:28:59 +01:00
Robert Mader
1d20045247 surface-actor: Fix memory leak
When we create a new region for an opaque texture we need to free it.
While on it, simplify the check slightly.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1108
2020-03-23 18:10:28 +00:00
Carlos Garnacho
c131a9b7fa backends/x11: Observe multiple pad mode switch buttons in a group
Some tablets like the Cintiq 24HDT have several mode switch buttons
per group. Those are meant to jump straight to a given mode, however
we just handle cycling across modes (as most other tablets have a
single mode switch button per group).

So spice up the mode switch handling so we handle multiple mode
switch buttons, assigning each of them a mode. If the device only
has one mode switch button, we do the old-fashioned cycling.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/970
2020-03-20 21:30:30 +01:00
Carlos Garnacho
2ecbf6d746 x11: Handle windowing errors while writing selection INCR data
This error was just logged but not raised. Do as the code comment said
and raise a pipe error at that moment, and for subsequent operations
on the output stream (although none besides close() should be expected
after propagating the error properly).

Related: https://gitlab.gnome.org/GNOME/mutter/issues/1065
2020-03-20 16:14:07 +01:00
Daniel Șerbănescu
a13d60aae5 Update Romanian translation 2020-03-19 10:59:57 +00:00
Robert Mader
ed4b80cee5 clutter/stage: Rename parameters to match documentation
To silence warnings during GIR generation.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1133
2020-03-18 02:45:43 +01:00
Jonas Ådahl
0a6034ef3a monitor-manager: Remove 'mirror' capability
With per-CRTC views, there is nothing stopping NVIDA EGLStream based
rendering to not support monitor mirroring, so lets remove that
restriction.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1098
2020-03-18 00:46:20 +00:00
Jonas Ådahl
c9a5b2b22f kms-impl-simple: Handle lack of cached mode set in flip fallback
When a page flip fails with a certain error code, we've treated this as
a hint that page flipping is broken and we should try to use mode
setting instead.

On some drivers, it seems that this error is also reported when there
was no mode set, which means we'll have no cached mode set to use in the
fallback. The lack of prior mode set tends to happen when we hit a race
when the DRM objects change before we have the time to process a hotplug
event.

Handle the lack a missing mode set in the flip fallback path, with the
assumption that we'll get a hotplug event that'll fix things up for us
eventually.

Closes: https://gitlab.gnome.org/GNOME/mutter/issues/917
2020-03-18 00:33:03 +00:00
Carlos Garnacho
db9b60cc63 wayland: Represent preedit string cursor offset in bytes
Both IBus and ClutterInputFocus work in character offsets for the cursor
position in the preedit string. However the zwp_text_input protocol does
define the preedit string cursor offset to be in bytes.

Fixes client bugs in representing the caret within the preedit string,
as we were clearly giving the wrong offset.

Fixes: https://gitlab.gnome.org/GNOME/gtk/issues/2517

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1132
2020-03-17 22:15:52 +00:00