Effects are given the interval between two consecutive frames. The main
flaw of this approach is that if the Compositor transitions from the idle
state to "active" state, i.e. when there is something to repaint,
effects may see a very large interval between the last painted frame and
the current. In order to address this issue, the Scene invalidates the
timer that is used to measure time between consecutive frames before the
Compositor is about to become idle.
While this works perfectly fine with Xinerama-style rendering, with per
screen rendering, determining whether the compositor is about to idle is
rather a tedious task mostly because a single output can't be used for
the test.
Furthermore, since the Compositor schedules pointless repaints just to
ensure that it's idle, it might take several attempts to figure out
whether the scene timer must be invalidated if you use (true) per screen
rendering.
Ideally, all effects should use a timeline helper that is aware of the
underlying render loop and its timings. However, this option is off the
table because it will involve a lot of work to implement it.
Alternative and much simpler option is to pass the expected presentation
time to effects rather than time between consecutive frames. This means
that effects are responsible for determining how much animation timelines
have to be advanced. Typically, an effect would have to store the
presentation timestamp provided in either prePaint{Screen,Window} and
use it in the subsequent prePaint{Screen,Window} call to estimate the
amount of time passed between the next and the last frames.
Unfortunately, this is an API incompatible change. However, it shouldn't
take a lot of work to port third-party binary effects, which don't use the
AnimationEffect class, to the new API. On the bright side, we no longer
need to be concerned about the Compositor getting idle.
We do still try to determine whether the Compositor is about to idle,
primarily, because the OpenGL render backend swaps buffers on present,
but that will change with the ongoing compositing timing rework.
The main advantage of SPDX license identifiers over the traditional
license headers is that it's more difficult to overlook inappropriate
licenses for kwin, for example GPL 3. We also don't have to copy a
lot of boilerplate text.
In order to create this change, I ran licensedigger -r -c from the
toplevel source directory.
Summary:
Currently code base of kwin can be viewed as two pieces. One is very
ancient, and the other one is more modern, which uses new C++ features.
The main problem with the ancient code is that it was written before
C++11 era. So, no override or final keywords, lambdas, etc.
Quite recently, KDE compiler settings were changed to show a warning if
a virtual method has missing override keyword. As you might have already
guessed, this fired back at us because of that ancient code. We had
about 500 new compiler warnings.
A "solution" was proposed to that problem - disable -Wno-suggest-override
and the other similar warning for clang. It's hard to call a solution
because those warnings are disabled not only for the old code, but also
for new. This is not what we want!
The main argument for not actually fixing the problem was that git
history will be screwed as well because of human factor. While good git
history is a very important thing, we should not go crazy about it and
block every change that somehow alters git history. git blame allows to
specify starting revision for a reason.
The other argument (human factor) can be easily solved by using tools
such as clang-tidy. clang-tidy is a clang-based linter for C++. It can
be used for various things, e.g. fixing coding style(e.g. add missing
braces to if statements, readability-braces-around-statements check),
or in our case add missing override keywords.
Test Plan: Compiles.
Reviewers: #kwin, davidedmundson
Reviewed By: #kwin, davidedmundson
Subscribers: davidedmundson, apol, romangg, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D22371
Summary:
This has basically been dead code for ages. The Shadow effect got
dropped in an early 4.x version. We shouldn't transform the window based
on old shadow values, so completely removed.
Reviewers: #kwin, #plasma
Subscribers: plasma-devel, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D3339
This method replaces the X-KDE-ORDERING property in the Effect's desktop
files. This change is a preparation step for integrating the new Effect
Loader which doesn't read the ordering information. Thus it needs to be
provided by the Effect itself so that the EffectsHandler can properly
insert it into the chain.
Also for the built-in Effects on the long run it doesn't make much sense
to install the desktop files. And binary plugin effects will migrate to
json metadata which also doesn't have the KService::Ptr. Thus overall it
simplifies to read this information directly from the Effect.
The supportInformation is extended to also read the properties
on all effects. In addition each effect can be queried just for
itself through D-Bus, e.g.:
qdbus org.kde.kwin /KWin supportInformationForEffect kwin4_effect_blur
All effects are extended to provide their configured and read
settings through properties. In some cases also important
runtime information is exposed.
REVIEW: 105977
BUG: 305338
FIXED-IN: 4.9.1
Each effect is able to declare itself as currently being active,
that is transforming windows or painting or screen or doing anything
during the current rendered frame.
This change eliminates the hottest path inside KWin identified by
callgrind.
REVIEW: 102449
The KWin::TimeLine class was only a small wrapper around QTimeLine
without adding anything to QTimeLine what is not present in QTimeLine.
The initial idea was to make it possible to provide more curve shapes.
This is now obsoleted by Qt shipping more useful curves with QTimeLine.
So let's clean up a little bit and use QTimeLine directly instead of
the small wrapper.
All effects are adjusted to use QTimeLine directly.
its own directory, cleaned up the effect config macros and renamed
"MakeTransparent" to "Translucency" so that it matches its visible name.
svn path=/trunk/KDE/kdebase/workspace/; revision=921749
