This separate thread submits commits as late as possible, so that until
immediately before vblank the cursor position can still be updated, reducing
its latency and opening the door for more optimizations.
This makes it possible to ensure type safety for enums, as each drm property
object can have its own type now, and it reduces the amount of typing needed
to access properties
Due to being a compositor, kwin has to conform to some certain
interfaces. It means a lot of virtual functions and function tables to
integrate with C APIs. Naturally, we not always want to use every
argument in such functions.
Since we get -Wunused-parameter from -Wall, we have to plumb those
unused arguments in order to suppress compiler warnings at the moment.
However, I don't think that extra work is worth it. We cannot change or
alter prototypes in any way to fix the warning the desired way. Q_UNUSED
and similar macros are not good indicators of whether an argument is
used too, we tend to overlook putting or removing those macros. I've
also noticed that Q_UNUSED are not used to guide us with the removal no
longer needed parameters.
Therefore, I think it's worth adding -Wno-unused-parameter compiler
option to stop the compiler producing warnings about unused parameters.
It changes nothing except that we don't need to put Q_UNUSED anymore,
which can be really cumbersome sometimes. Note that it doesn't affect
unused variables, you'll still get a -Wunused-variable compiler warning
if a variable is unused.
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:
The addition of the test infrastructure is motivated by the regressions
caused by adding mode switching and transformation support.
A contributing factor to these regression is the fact that the DRM
platform does not have any tests. It is difficult to test this code as
it needs to work with hardware, thus we cannot use the real DRM library.
Instead we need to use mocking.
This change sets up some first basic tests with the help of a mockDrm
library. In order to better test the code as units the Drm classes are
slightly refactored. Most importantly the dependency to DrmBackend is
removed wherever possible and replaced by a simple int fd which is mostly
the only element used by the classes.
This first test introduces basic testing of a DrmObject. It is intended
to extend this to at least also test DrmPlane as a central piece of our
Drm platform plugin. This will also extend the tests of DrmObject.
Reviewers: #kwin, #plasma
Subscribers: plasma-devel
Tags: #plasma
Differential Revision: https://phabricator.kde.org/D8776
Laurent Montel