QQuickRenderControl brings a few advantages for the usage in Aurorae:
* can create an offscreen window
* eliminate the need for mutex as we control the rendering
* control the tear down of the QML scene (no more crashes in Qt)
In future we can further improve this, by sharing the context, so
that we can use the FBO texture directly. But this first needs
some more work in KWin core.
As we don't hard depend on Qt 5.4 yet it's using ifdefs. Once we have
Qt 5.4 the old code will be removed.
Adjust all components to use the QSharedPointer. Aurorae obviously has
to create a QSharedPointer, Shadow holds a QSharedPointer for the
DecorationShadow (advantage: is kept when the Decoration is destroyed),
and the KCM needs to add a property on PreviewItem to get access to the
Shadow. It's no longer a Q_PROPERTY on Decoration and we cannot re-add
it as a dynamic property (cannot be read from QML side).
* Aurorae needs to pass QVariantList args to parent Decoration
* DecorationBridge implementation needs to be a KWIN_SINGLETON
* DecorationBridge needs to be passed with args to created Decoration
The idea behind the ThemeFinder is to expose a way for a configuration
module to find all themes. The API is not yet finalized, thus it's just
a QObject with a Q_PROPERTY themes of type QVariantMap with key being
the user visible name and value being the internal theme name.
The ThemeFinder will have to be moved to KDecoration library.
The json metadata provides a "themeListKeyword" which is used as the
keyword to the KPluginFactory.
DecorationShadow is supported through using the padding values. The
window becomes larger by the padding and gets positioned accordingly.
This requires to translate all mouse events.
The DecorationShadow is just using the complete image, which is kind of
a memory waste, but at least the SVG based Aurorae doesn't provide us
better information (might be added, but would probably need changes in
the theme).
For switching back to non-compositing we recreate the QuickWindow. It's
not fortunate, but as long as we do not yet have the render control it's
needed.
The port to KDecoration2 means quite some changes in the way how Aurorae
works. First of all: the theme to load is passed to the Deocoration ctor
and not searched for by Aurorae itself.
The rendering mechanismn didn't change significantly yet. It's still
rendering to an FBO and passing the image on. This needs some further
work as KDecoration2 does not support the padding any more. So all
themes using shadow are currently broken.
Another big change is the way how the rendering scene is constructed
and used. KDecoration2 doesn't want the the Decoration to be a native
window. But for being able to render a QtQuick scene at all we need a
QQuickWindow. Thus it creates a window parented to the decoration id,
but not accepting any input event. Input is nowadays controlled from
the outside: events are passed into the Decoration, so we don't want
the QtQuick window intercepting events.
In case of non-composited the normal FBO mechanism doesn't work and
Aurorae just renders to the QQuickWindow directly. This could use
some optimization in the decoration renderer in KWin core to not even
try to perform the normal rendering. On the other hand it's probably
too much a hassle for the use case.
The rendering architecture might hopefully be improved with Qt 5.4
and the new QQuickRenderControl class.
The QQuickWindow also exposes a problem for preview in the
kdecoration-viewer and the future KCM: we don't want a different
window, but best would be to get to the QML scene directly. A small
hack is added to have the previewers set a "visualParent" which Aurorae
uses to parent the QML scene to without the need to create a
QQuickWindow.
The Text.horizontalAlignment property expects AlignHCenter instead of
AlignCenter. By not using AlignHCenter the centering broke when a window
got maximized.
It's possible that the rendering thread is still writing to the
buffer and if we destroy the buffer before it's finished KWin is going
to crash. So let's mutex lock the dtor to ensure that the rendering
thread finishes before we tear down the client.
BUG: 336950
Seems like porting to new infrastructure was incomplete. The
MaximizeRestore button consists of two buttons on top of each other with
an own mouse area in each and both always visible. This means the restore
button was stealing the mouse events of the maximize button breaking
maximization.
The solution is to have an additional MouseArea which controls the whole
button making the two button types just visualization.
The position passed to core didn't take care of padding and that position
passed to decorationPos caused completely broken resize/moving behavior.
E.g. resize was started where it should have been moving, or jumping of
position when starting moving.
REVIEW: 118803
The KWin::Borders element is provided by an extension plugin. The reason
for that is to be able to use it from e.g. the kcm or Plasmate without
needing to compile the code in.
But this results in Aurorae itself not being able to access the element.
The solution is to first load our decoration plugin and afterwards
register the borders element again with the version compiled in from
Aurorae.
With that we can now read all borders and paddings without using
properties. Also we could connect to change signals and have the borders
and padding handling completely stateful. Might be an idea for extending
the decoration library...
Qml based Aurorae themes can provided a ui file which gets loaded at
runtime. Obviously such a ui file is not translated. This introduces
quite a hack to load the translated strings.
First of all a new property is added to the service file for
specifying the translation domain to be used for the config UI. If
such a translation domain is set we extract all string properties of
the loaded UI and pass them through ki18nd.
