Planet KDE

Let’s go for my web review for the week 2024-46.

No GPS required: our app can now locate underground trains

Tags: tech, mobile, sensors, gps, transportation

Now this is definitely a smart trick to estimate position in tunnels.

https://blog.transitapp.com/go-underground/

OpenAI, Google and Anthropic Are Struggling to Build More Advanced AI - Bloomberg

Tags: tech, ai, machine-learning, gpt

More signs of the generative AI companies hitting a plateau…

https://www.bloomberg.com/news/articles/2024-11-13/openai-google-and-anthropic-are-struggling-to-build-more-advanced-ai

Releasing the largest multilingual open pretraining dataset

Tags: tech, ai, machine-learning, gpt, data, copyright, licensing

It shouldn’t be, but it is a big deal. Having such training corpus openly available is one of the big missing pieces to build models.

https://simonwillison.net/2024/Nov/14/releasing-the-largest-multilingual-open-pretraining-dataset/#atom-blogmarks

Everything I’ve learned so far about running local LLMs

Tags: tech, ai, machine-learning, gpt, foss

This is an interesting and balanced view. Also nice to see that local inference is really getting closer. This is mostly a UI problem now.

https://nullprogram.com/blog/2024/11/10/

When Machine Learning Tells the Wrong Story

Tags: tech, cpu, hardware, security, privacy, research

Fascinating research about side-channel attacks. Learned a lot about them and website fingerprinting here. Also interesting the explanations of how the use of machine learning models can actually get in the way of proper understanding of the side-channel really used by an attack which can prevent developing actually useful counter-measures.

https://jackcook.com/2024/11/09/bigger-fish.html

Abusing Ubuntu 24.04 features for root privilege escalation

Tags: tech, linux, security

Nice chain of attacks. This shows more than one vulnerability needs to be leveraged to lead to root access. This provides valuable lessons.

https://snyk.io/blog/abusing-ubuntu-root-privilege-escalation/

Way too many ways to wait on a child process with a timeout

Tags: tech, unix, linux, system

The title says it all. This is very fragmented and there are several options to fulfill the task. Knowing the tradeoffs can be handy.

https://gaultier.github.io/blog/way_too_many_ways_to_wait_for_a_child_process_with_a_timeout.html

The CVM Algorithm

Tags: tech, databases, algorithm

This is a nice view into how a query planner roughly works and a nice algorithm which can be used internally to properly estimate the number of distinct values in a column.

https://buttondown.com/jaffray/archive/the-cvm-algorithm/

Mergiraf

Tags: tech, version-control, git, tools, conflict

Looks like a nice way to improve handling of merge conflicts. I’ll test this one out.

https://mergiraf.org/

Opposite of Cloud Native is?

Tags: tech, cloud, complexity, vendor-lockin, self-hosting

Definitely a good post. No you don’t have to go all in with cloud providers and signing with your blood. It’s often much more expensive for little gain but much more complexity and vendor lock in.

https://mkennedy.codes/posts/opposite-of-cloud-native-is-stack-native/

Booleans Are a Trap

Tags: tech, design, type-systems

Avoiding boolean parameters in library APIs should be a well known advice by now. Still they should probably be avoided when modeling domain types as well.

https://katafrakt.me/2024/11/09/booleans-are-a-trap/

Complex for Whom?

Tags: tech, design, complexity

Good musing about complexity. Very often we need to move it around, the important question is where should it appear. For sure you don’t want it scattered everywhere.

https://notes.billmill.org/link_blog/2024/11/Complex_forWhom.html

What makes concurrency so hard?

Tags: tech, distributed, complexity

Interesting reasoning about what is hard in systems with concurrency. It’s definitely about the state space of the system and the structure of that space.

https://buttondown.com/hillelwayne/archive/what-makes-concurrency-so-hard/

Algorithms we develop software by

Tags: tech, programming, craftsmanship, engineering, problem-solving

Interesting musing on the heuristics we use when solving problems. There are good advices in there to make progress and become a better developer.

https://grantslatton.com/software-pathfinding

Bye for now!

KDE Gear is our release service for many apps such as mail and calendaring supremo Kontact, geographers dream Marble, social media influencing Kdenlive and dozens of others. KDE needs you to test that your favourite feature has been added and your worst bug has been squished.

You can do this with KDE neon Testing edition, built from the Git branches which get used to make releases from. You can download the ISO and try it on spare hardware or on a virtual machine to test them out.

But maybe you don’t want the faff of installing a distro. Containers give an easier way to test thanks to Distrobox.

Install Distrobox on your normal computer. Make sure Docker or podman are working.

Download the container with

distrobox create -i invent-registry.kde.org/neon/docker-images/plasma:testing-all

Then start it with
distrobox enter all-testing
And voila it will mount the necessary bits to get Wayland connections working and keep your home directory available and you can run say

kontact

and test the beta for the mail app.

All of KDE's Google Summer of Code (GSoC) projects are complete.

GSoC is a program where students or people who are new to Free and Open Source software make programming contributions to an open source project.

This post summarizes the outcomes of KDE project participating in GSoC 2024.

Projects Arianna

• Port Arianna to Foliate-js:

Ajay Chauhan worked on porting Arianna from epub.js to use Foliate-js. The work will hopefully be merged soon.

A screenshot of Arianna using Foliate-js to render a table of contents
(Courtesy of Ajay Chauhan, CC BY-NC-SA 4.0) Frameworks

Python bindings for KDE Frameworks:

Manuel Alcaraz Zambrano, implemented Python bindings for KWidgetAddons, KUnitConversion, KCoreAddons, KGuiAddons, KI18n, KNotifications, and KXmlGUI. This was done using Shiboken. In addition, Manuel wrote a tutorial on how to generate Python bindings using Shiboken. The complicated set of merge requests are still being reviewed, and Manuel continues to interact with the KDE community.

Unit conversion example created using Python and KUnitConversion
(Courtesy of Manuel Alcaraz Zambrano, CC BY-NC-SA 4.0) KDE Connect

Update SSHD library in KDE Connect Android app

The main aim of ShellWen Chen's project was to update Apache Mina SSHD from 0.14.0 to 2.12.1. The older version has a few listed vulnerabilities. The newer library required additional code to enable it to work on older Android phones, up to Android API 21.

KDE Games

Implementing a computerized opponent for the Mancala variant Bohnenspiel:

João Gouveia created Mankala engine, a library to enable easy creation of Mancala games. The engine contains implementations for two Mancala games, Bohnenspiel and Oware. Both games contain computerized opponents, João also started on a QtQuick graphical user interface. The games are functional, but additional investigation on computerized opponents may help improve their effectiveness.

Image of text user interface for Bohnenspiel
(Courtesy of João Gouveia, CC BY-SA 4.0) Kdenlive

Improved subtitling support for Kdenlive:

Subtitling support has been improved for Kdenlive. Chengkun Chen added support for using the Advanced SubStation (ASS) file format and for converting SubRip files to ASS files. To support this format, Chengkun Chen also made subtitling editor improvements. The work has been merged in the main repository. Documentation has been written, and will hopefully be merged soon.

The new Style Editor Widget
(Courtesy of Chengkun Chen, CC BY-SA 4.0) Krita

Creating Pixel Perfect Tool for Krita:

Ken Lo worked on implementing Pixel Perfect lines in Krita. As explained by Ricky Han, such algorithms remove corner pixels from L shaped blocks and ensure the thinnest possible line is 1 pixel wide. Implementing such algorithms well is of use not only in Krita, but also in rendering web graphics where user screen resolutions can vary significantly. The algorithm was implemented to work in close to real time while lines are drawn, rather than as a post processing step. Ken Lo's work has been merged into Krita.

An image showing that pixel perfect lines are obtained most of the time
(Courtesy of Ken Lo, CC BY 4.0) Labplot

Improve Python Interoperability with LabPlot

Israel Galadima worked on improving Python support in LabPlot. Shiboken was used for this and it is now possible to call some of LabPlot functions from Python and integrate these into other applications.

An image of a plot produced using Python bindings to Labplot
(Courtesy of Israel Galadima, CC BY-SA 4.0)

3D Visualization for LabPlot:

Kuntal Bar added 3D graphing capabilities to LabPlot. This was done using QtGraphs. The work has yet to be merged, but there are many nice examples of 3D plots for bar charts, scatter and surface plots.

A 3D bar chart
(Courtesy of Kuntal Bar, MIT license) Okular

Forms/Javascript support improvement for Okular:

Pratham Gandhi worked on improving the forms/Javascript support in Okular. Around 25 requests have been merged to improve various features, some in the backend and some directly visible, such as fixing the size of the radio buttons or check boxes, or the one pictured below to improve the handling of floating numbers in different locales.

An image of showing an incorrect total sum calculation fixed during GSoC
(Courtesy of Pratham Gandhi, CC BY-SA 4.0) Snaps

Improving Snap Ecosystem in KDE:

Snaps are self contained linux application packging formats. Soumyadeep Ghosh worked on improving the tooling necessary to make KDE applications easily available in the Snap Store. In addition, Soumyadeep improved packaging of a number of KDE Snap packages, and packaged MarkNote. Finally, Soumyadeep created Snap KCM, a graphical user interface to manage permissions that Snaps have when running.

Snap KCM
(Courtesy of Soumyadeep Ghosh, CC BY-NC-SA 4.0) Next Steps

The 2024 GSoC period is finally over for KDE. A big thank you to all the mentors and contributors who have participated in GSoC! We look forward to your continuing participation in free and open source software communities and in contributing to KDE.

Qt Creator 14 has removed support for its Python 2 pretty printers.

Earlier this year I had the pleasure of visiting the KDE Akademy 2024 in Würzburg. It had been a few years since my last visit to Akademy and it was great to see old friends and meet new ones. Besides socializing, my main task was to talk to as many KDE people as possible about the privact project and its integration into KDE. Knowing the KDE community, not surprisingly this resulted in lots of interesting discussions.

Most importantly, I gave a talk about the current state of privact’s integration with KUserFeedback. If you missed it, here is the recording:

As a follow-up, we had 2 BoFs on Monday to discuss the next steps. Felix was kind enough to join me to provide more technical developer insights than I can give.

As a first teaser for you: In the short term, the private approach will allow KDE to do proper user research, thereby enabling us to do data-driven UX without compromising user privacy. In the longer term, privact aims to restore digital privacy for everyone, even outside of KDE, even outside of FLOSS. You can learn more in upcoming posts or on the privact homepage.

The individual feedback on the privact approach during Akademy was very good, which is why we now want to start communicating with the larger KDE community. So this post is not only to report about my attendance at the Akademy, but also to start blogging again on Planet KDE and to check if the aggregation works.

Hello World Planet!

We are happy to announce the release of Qt Creator 15 RC!

At the International TeX Users Group Conference 2023 (TUG23) in Bonn, Germany, I presented a talk about using Metafont (and its extension Metapost) to develop traditional orthography Malayalam fonts, on behalf of C.V. Radhakrishnan and K.H. Hussain, who were the co-developers and authors. And I forgot to post about it afterwards — as always, life gets in between.

In early 2022, CVR started toying with Metafont to create a few complicated letters of Malayalam script and he showed us a wonderful demonstration that piqued many of our interest. With the same code base, by adjusting the parameters, different variations of the glyphs can be generated, as seen in a screenshot of that demonstration: 16 variations of the same character ഴ generated from same Metafont source.

Hussain, quickly realizing that the characters could be programmatically assembled from a set of base/repeating components, collated an excellent list of basic shapes for Malayalam script.

Excerpts from the Malayalam character basic shape components documented by K.H. Hussain.

I bought a copy of ‘The Metafontbook’ and started learning and experimenting. We found soon that Metafont, developed by Prof. Knuth in the late 1970’s, generates bitmap/raster output; but its extension MetaPost, developed by his Ph.D. student John Hobby, generates vector output (postscript) which is required for opentype fonts. We also found that ‘Metatype1’ developed by Bogusław Jackowski et al. has very useful macros and ideas.

We had a lot of fun programmatically generating the character components and assembling them, splicing them, sometimes cutting them short, and transforming them in all useful manner. I have developed a new set of tools to generate the font from the vector output (SVG files) generated by MetaPost, which is also used in later projects like Chingam font.

At the annual TUG conference 2023 in Bonn, Germany, I have presented our work, and we received good feedback. There were three presentations about Metafont itself at the conference. Among others, I also had the pleasure to meet Linus Romer who shared some ideas about designing variable width reph-shapes for Malayalam characters.

The video of the presentation is available in YouTube.

The article was published in the TUGboat conference proceedings (volume 44): https://www.tug.org/TUGboat/tb44-2/tb137radhakrishnan-malayalam.pdf

Postscript (no pun intended): after the conference, I visited some of my good friends in Belgium and Netherlands. En route, my backpack with passport, identity cards, laptop, a phone and money etc. was stolen at Liège. I can’t thank enough my friends at Belgium and back at home for all their care and help, in the face of a terrible experience. On the day before my return, the stolen backpack with everything except the money was found by the railway authorities and I was able to claim it just in time.

I made yet another visit to the magnificent Plantin–Moretus Museum (it holds the original Garamond types!), where I myself could ink and print a metal typeset block of sonnet by Christoffel Plantijn in 1575, which now hangs at the office of a good friend.

My first in-person Akademy: Thessaloniki 2023

This year, I was finally able to participate in-person at Akademy. Apart from meeting some familiar faces from the Plasma Spring in May this year, I also met lots of new people.

When waiting for the plane in Frankfurt, a group of KDE people formed. Meaning, we had a get-together even before the Akademy had started ;). On the plane to Thessaloniki, I made a merge requests to fix a Kickoff crash due to a KRunner change. Once that was done, everything was in place for the talks!

On Saturday, I talked once again with Nico and also Volker about KF6. This included topics like the remaining challenges, the estimated timeline for KF6 and some practical porting advice. I also gave a talk about KRunner. This was the conference talk of mine that I gave alone, meaning I was a bit nervous 😅. The title was “KRunner: Past, Present, and Future” and it focused on porting, new features and future plans for KF6. Thanks to everyone who was listening to the talk, both in person and online! Some things like the multithreading refactoring are worth their own blog post, which I will do in the next weeks.

The talks from other community members were also quite interesting. Sometimes it was hard to decide to which talk to go :). Multiple talks and BoFs were about energy efficiency and doing measurements. This perfectly aligned with me doing benchmarking of KRunner and the KCoreAddons plugin infrastructure.

The view of the city from the hotel balcony was also quite nice

Our KF6 and Qt6 porting BoFs were also quite productive. On Tuesday, we had our traditional KF6 weekly. Having this in person was definitely a nice refreshment! Apart from some general questions about documentation and KF6 Phabricator tasks, we discussed the release schedule. The main takeaway is that we want to improve the release automation and have created a small team to handle the KDE Frameworks releases. This includes Harald Sitter, Nicolas Fella, David Edmundson and me. Feel free to join the weeklies in our Big Blue Button room https://meet.kde.org/b/ada-mi8-aem at 17:00 CEST each Tuesday.

Since we had so many talented KDE people in one place, I decided to have a KRunner BoF on Tuesday morning. Subject of discussion was for example the sorting of KRunner, how to better organize the categories and the revival of the so-called “single runner mode”. This mode allows you to query only one specific plugin, instead of all available ones. This was previously only available from the D-Bus interface, but I have added a command line option to KRunner. To better visualize this special mode being in use, a tool-button was added as an indicator. This can also be used to go back to querying all runners. Kai will implement clickable categories that allow you to enable this mode without any command line options being necessary!

Finally, I would like to thank everyone who made this awesome experience possible! I am already looking forward to the next Akademy and the next sprints.

Unifying the KRunner sorting mechanisms for Plasma6 & further plans

In Plasma5, we had different sorting implementations for KRunner and Kicker. This had historical reasons, because Kicker only used a subset of the available KRunner plugins. Due to the increased reliability, we decided to allow all available plugins to be loaded. However, the model still hard-coded the order in which the categories are displayed. This was reported in this bug which received numerous duplicates.

To address this concern, I focused on refactoring and cleaning up KRunner as part of KDE Frameworks 6. Among the significant architectural changes was the integration of KRunner’s model responsible for sorting into the KRunner framework itself. This integration enabled easier code sharing and simplified code maintenance. Consequently, the custom sorting logic previously present in Kicker could be removed.

Further plans

Now you know some of the improvements that have been done, but more interesting might be the future plans! While the sorting in KRunner was in lots of regards better than the one from Kicker, it still has some flaws. For instance, tweaking the order of results from a plugin developer’s perspective proved challenging, since rearranging categories could occur unintentionally. Also, KRunner implements logic to prioritize often launched results. In practice, this did not work quite well, because it only changed one of two sorting factors that are basically the same (sounds messy, I know :D).

The plan is to have two separate sorting values: One for the categories and one for the results within a category. This allows KRunner to more intelligently learn which categories you use more the most and prioritize them for further queries.

Another feature request to configure the sorting of plugins. With the described change, this is far easier to implement. Some of the visuals were already discussed at the Plasma sprint last month.

Stay tuned for updates!

The goal

When building C++ code with CMake, it is very common to want to set some pre-processor defines in the CMake code.

For instance, we might want to set the project’s version number in a single place, in CMake code like this:

project(MyApp VERSION 1.5)

This sets the CMake variable PROJECT_VERSION to 1.5, which we can then use to pass -DMYAPP_VERSION_STRING=1.5 to the C++ compiler. The about dialog of the application can then use this to show the application version number, like this:

const QString aboutString = QStringLiteral("My App version: %1").arg(MYAPP_VERSION_STRING); QMessageBox::information(this, "My App", aboutString);

Similarly, we might have a boolean CMake option like START_MAXIMIZED, which the user compiling the software can set to ON or OFF:

option(START_MAXIMIZED "Show the mainwindow maximized" OFF)

If it’s ON, you would pass -DSTART_MAXIMIZED, otherwise nothing. The C++ code will then use #ifdef. (We’ll see that there’s a better way.)

#ifdef START_MAXIMIZED w.showMaximized(); #else w.show(); #endif The common (but suboptimal) solution

A solution that many people use for this is the CMake function add_definitions. It would look like this:

add_definitions(-DMYAPP_VERSION_STRING="${PROJECT_VERSION}") if (START_MAXIMIZED) add_definitions(-DSTART_MAXIMIZED) endif()

Technically, this works but there are a number of issues.

First, add_definitions is deprecated since CMake 3.12 and add_compile_definitions should be used instead, which allows to remove the leading -D.

More importantly, there’s a major downside to this approach: changing the project version or the value of the boolean option will force CMake to rebuild every single .cpp file used in targets defined below these lines (including in subdirectories). This is because add_definitions and add_compile_definitions ask to pass -D to all cpp files, instead of only those that need it. CMake doesn’t know which ones need it, so it has to rebuild everything. On large real-world projects, this could take something like one hour, which is a major waste of time.

A first improvement we can do is to at least set the defines to all files in a single target (executable or library) instead of “all targets defined from now on”. This can be done like this:

target_compile_definitions(myapp PRIVATE MYAPP_VERSION_STRING="${PROJECT_VERSION}") if(START_MAXIMIZED) target_compile_definitions(myapp PRIVATE START_MAXIMIZED) endif()

We have narrowed the rebuilding effect a little bit, but are still rebuilding all cpp files in myapp, which could still take a long time.

The recommended solution

There is a proper way to do this, such that only the files that use these defines will be rebuilt; we simply have to ask CMake to generate a header with #define in it and include that header in the few cpp files that need it. Then, only those will be rebuilt when the generated header changes. This is very easy to do:

configure_file(myapp_config.h.in myapp_config.h)

We have to write the input file, myapp_config.h.in, and CMake will generate the output file, myapp_config.h, after expanding the values of CMake variables. Our input file would look like this:

#define MYAPP_VERSION_STRING "${PROJECT_VERSION}" #cmakedefine01 START_MAXIMIZED

A good thing about generated headers is that you can read them if you want to make sure they contain the right settings. For instance, myapp_config.h in your build directory might look like this:

#define MYAPP_VERSION_STRING "1.5" #define START_MAXIMIZED 1

For larger use cases, we can even make this more modular by moving the version number to another input file, say myapp_version.h.in, so that upgrading the version doesn’t rebuild the file with the showMaximized() code and changing the boolean option doesn’t rebuild the about dialog.

If you try this and you hit a “file not found” error about the generated header, that’s because the build directory (where headers get generated) is missing in the include path. You can solve this by adding set(CMAKE_INCLUDE_CURRENT_DIR TRUE) near the top of your CMakeLists.txt file. This is part of the CMake settings that I recommend should always be set; you can make it part of your new project template and never have to think about it again.

There’s just one thing left to explain: what’s this #cmakedefine01 thing?

If your C++ code uses #ifdef, you want to use #cmakedefine, which either sets or doesn’t set the define. But there’s a major downside of doing that — if you forget to include myapp_config.h, you won’t get a compile error; it will just always go to the #else code path.

We want a solution that gives an error if the #include is missing. The generated header should set the define to either 0 or 1 (but always set it), and the C++ code should use #if. Then, you get a warning if the define hasn’t been set and, because people tend to ignore warnings, I recommend that you upgrade it to an error by adding the compiler flag -Werror=undef, with gcc or clang.  Let me know if you are aware of an equivalent flag for MSVC.

if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang") target_compile_options(myapp PRIVATE -Werror=undef) endif()

And these are all the pieces we need. Never use add_definitions or add_compile_definitions again for things that are only used by a handful of files. Use configure_file instead, and include the generated header. You’ll save a lot of time compared to recompiling files unnecessarily.

I hope this tip was useful.

For more content on CMake, we curated a collection of resources about CMake with or without Qt. Check out the videos.

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It was once said over the grapevine that: "Our C++ API documentation has some issues, our QML API documentation has a lot of issues."

And it was true, but that is to change soon! As you might know, there is an ongoing effort to port our documentation from Doxygen to QDoc, and you can help with that.

This is a task that has been adopted by the Streamlined Application Development Experience championed by Nicolas Fella and Nate Graham as part of the KDE Goals initiative.

We would like to invite you to join our porting sprint effort to finish this task. On November 14th at 1PM UTC, we'll be hanging out in the Matrix room working on this. Hope to see you there.

Some prerequisites:

• Ability to use a terminal
• Extra disk space (30GB minimum)
• Some familiarity with APIs

Check out the instructions prepared by Thiago Sueto on how to get started porting a project to QDoc.

Welcome to the @Krita-promo team's October 2024 development and community update.

Development Report Android-only Krita 5.2.8 Hotfix Release

Krita 5.2.6 was reported to crash on startup on devices running Android 14 or later. This was caused by issues with an SDK update required for release on the Play Store, so a temporary 5.2.7 release reverting it was available from the downloads page only.

However, the issue has now been resolved and 5.2.8 is rolling out on the Play Store. Note that 5.2.8 raises the minimum supported Android version to Android 7.0 (Nougat).

Community Bug Hunt Started

The development team has declared a "Bug Hunt Month" running through November, and needs the community's help to decide what to do with each and every one of the hundreds of open bug reports on the bug tracker. Which reports are valid and need to be fixed? Which ones need more info or are already resolved?

Read the bug hunting guide and join in on the bug hunt thread on the Krita-Artists forum.

Community Report October 2024 Monthly Art Challenge Results

For the "Buried, Stuck, or otherwise Swallowed" theme, 16 members submitted 18 original artworks. And the winner is… Tomorrow, contest… I’m so finished by @mikuma_poponta!

The November Art Challenge is Open Now

For the November Art Challenge, @mikuma_poponta has chosen "Fluffy" as the theme, with the optional challenge of making it "The Ultimate Fluffy According to Me". See the full brief for more details, and get comfortable with this month's theme.

Featured Artwork Best of Krita-Artists - September/October 2024

8 images were submitted to the Best of Krita-Artists Nominations thread, which was open from September 14th to October 11th. When the poll closed on October 14th, moderators had to break a four-way tie for the last two spots, resulting in these five wonderful works making their way onto the Krita-Artists featured artwork banner:

Sapphire by @Dehaf

Sci-Fi Spaceship by @NAKIGRAL

Oracular Oriole by @SylviaRitter

Air Port by @agarad

Dancing with butterflies 🦋 by @Kichirou_Okami

Best of Krita-Artists - October/November 2024

Nominations were accepted until November 11th. The poll is now open until November 14th. Don't forgot to vote!

Ways to Help Krita

Krita is Free and Open Source Software developed by an international team of sponsored developers and volunteer contributors.

Visit Krita's funding page to see how user donations keep development going, and explore a one-time or monthly contribution. Or check out more ways to Get Involved, from testing, coding, translating, and documentation writing, to just sharing your artwork made with Krita.

The Krita-promo team has put out a call for volunteers, come join us and help keep these monthly updates going.

Notable Changes

Notable changes in Krita's development builds from Oct. 10 - Nov. 12, 2024.

Stable branch (5.2.9-prealpha):

• Layers: Fix infinite loop when a clone layer is connected to a group with clones, and a filter mask triggers an out-of-bounds update. (Change, by Dmitry Kazakov)
• General: Fix inability to save a document after saving while the image is busy and then canceling the busy operation. (bug report) (Change, by Dmitry Kazakov)
• Resources: Fix crash when re-importing a resource after modifying it. (bug report) (Change, by Dmitry Kazakov)
• Brush Presets: Fix loading embedded resources from .kpp files. (bug report, bug report, bug report) (Change, by Dmitry Kazakov)
• Brush Tools: Fix the Dynamic Brush Tool to not use the Freehand Brush Tool's smoothing settings which it doesn't properly support. (bug report) (Change, by Mathias Wein)(Change, by Dmitry Kazakov)
• Recorder Docker: Prevent interruption of the Text Tool by disabling recording while it is active. (bug report) (Change, by Dmitry Kazakov)
• File Formats: EXR: Possibly fix saving EXR files with extremely low alpha values. (Change, by Dmitry Kazakov)
• File Formats: EXR: Try to keep color space profile when saving EXR of incompatible type. (Change, by Dmitry Kazakov)
• File Formats: EXR: Fix bogus offset when saving EXR with moved layers. (Change, by Dmitry Kazakov)
• File Formats: JPEG-XL: Fix potential lockup when loading multi-page images. (Change, by Rasyuqa A H)
• Keyboard Shortcuts: Set the default shortcut for Zoom In to = instead of +. (bug report) (Change, by Halla Rempt)
• Brush Editor: Make the Saturation and Value brush options' graph and graph labels consistently agree on the range being -100% to 100% with 0% as neutral. (bug report) (Change, by Dmitry Kazakov)

Unstable branch (5.3.0-prealpha):

Bug fixes:

• Vector Layers: Fix endlessly slow rendering of vector layers with clipping masks. (bug report) (Change, by Dmitry Kazakov)
• Layers: Fix issue with transform masks on group layers not showing until visibility change, and visibility change of passthrough groups with layer styles causing artifacts. (bug report) (Change, by Dmitry Kazakov)
• Brush Editor: Fix crash when clearing scratchpad while it's busy rendering a resource-intensive brushstroke. (bug report) (Change, by Dmitry Kazakov)
• File Formats: EXR: Add GUI option for selecting the default color space for EXR files. (Change, by Dmitry Kazakov)
• Transform Tool: Liquify: Move the Move/Rotate/Scale/Offset/Undo buttons to their own spot instead of alongside unrelated options, to avoid confusion. (bug report) (Change, by Emmet O'Neill)
• Move Tool: Fix Force Instant Preview in the Move tool to be off by default. (CCbug report) (Change, by Halla Rempt)
• Pop-Up Palette: Fix lag in selecting a color in the Pop-Up Palette. (bug report) (Change, by Dmitry Kazakov)
• Scripting: Fix accessing active node state from the Python scripts. (bug report) (Change, by Dmitry Kazakov)
• Usabillity: Remove unnecessary empty space at the bottom of Transform, Move and Crop tool options. (bug report) (Change, by Dmitry Kazakov)

Nightly Builds

Pre-release versions of Krita are built every day for testing new changes.

Get the latest bugfixes in Stable "Krita Plus" (5.2.9-prealpha): Linux - Windows - macOS (unsigned) - Android arm64-v8a - Android arm32-v7a - Android x86_64

Or test out the latest Experimental features in "Krita Next" (5.3.0-prealpha). Feedback and bug reports are appreciated!: Linux - Windows - macOS (unsigned) - Android arm64-v8a - Android arm32-v7a - Android x86_64

Have feedback?

Join the discussion of this post on the Krita-Artists forum!

It’s been a minute!

We have been hard at work making sure our design system keeps moving forward. For the past weeks, we have made significant progress in the space of color creation and icons.

There is also an easter egg in the form of PenPot. Read the rest!

As previously mentioned, we restructured our color palettes to have set color variations at various levels. We will combine those colors into tokens that will be named something like this:

pd.sys.color.red50

Meaning:

• PD: Plasma Design
• SYS: System token (We also have reference tokens and component tokens, .ref. and .com. respectively)
• Color: Token type
• red50: color name + color value

Note that as we follow Material design guidelines for these colors, we have a collection of 100 different color shades for a given color. Depending on the needs of the system or changes in design, we could decide to not use red50 but we would like more intensity. So we would choose red49, or red48, and so on.

The color variable name would change accordingly. This set up would allow designers and developers to understand the kind of token they are working with and it would be the same language for both developer and designer.

In Figma and PenPot, designers have the ability to name tokens however they like. I opted for keeping token names as we are recommending them for the Plasma system. That way there is good consistency.

This week, we consolidated these colors and we added them to the list of tokens in Figma and PenPot. However, there is still more to be done in the form of documentation for our Plasma developer team. We are still working through it, making sure we are accurate in the request for development.

Additionally, this week we had the pleasure to meet with Pablo Ruiz, CEO at PenPot. Mike, one of our team members met Pablo recently and spoke of our Plasma Next project. This led to a meeting to discuss the needs that our team currently has for developing a design system.

The team at PenPot is excited to partner with our KDE team and the Plasma Next initiative. They have generously offered a few resources to help.

This couldn’t come at a better time as very recently we have been hitting gaps in our team knowledge when it comes to developing design systems. This process is a first for our desktop system and we want to get it right. With the help of the PenPot team and the changes they are making to the application, this should be easier.

As such, we also decided to request prioritization for some of our tickets that would allow us to set up and migrate our Figma assets into PenPot and eventually, share these with the community at large.

Today, we are not close to releasing a full design system for others to use, but we are making good progress. Stay tuned!

We also moved into the process of editing 16px icons. Given that we already have new icons in the 24px collection that we can leverage, we cut the design time in half or more. We don’t have to brainstorm new icons, we mostly just have to edit the 24px icon and adapt it to a 16px version. This work just barely started but we are making good progress.

One area that is still up in the air is our colorful icons. Given we edited the monochrome icons, this calls for editing colorful icons as well. We have received many suggestions on what kind of colorful style we should follow. I would like to extend that invitation.

If you have seen or created amazing colorful icons and would like to suggest that style for us at Plasma, send us a comment!

That’s it for this week. Good progress so far!

Welcome to a new issue of "This Week in KDE Apps"! Every week we cover as much as possible of what's happening in the world of KDE apps.

This week, we released KDE Gear 24.08.3 and we are preparing the 24.12.0 release with the beta planned for next week. The final release will happen on December 12th, but, meanwhile, and as part of the 2024 end-of-year fundraiser, you can "Adopt an App" in a symbolic effort to support your favorite KDE app.

This week, we are particularly grateful to @petejones@hcommons.social, @DaisyLee@mastodon.social and Karcsesz for showing their support for Tokodon; manchicken for Merkuro and fat_malama, Alexandru Traistaru and Neeko iko for KDE Connect.

Any monetary contribution, however small, will help us cover operational costs, salaries, travel expenses for contributors and in general just keep KDE bringing Free Software to the world. So consider donating today!

Getting back to all that's new in the KDE App scene, let's dig in!

Alligator Feed reader for mobile devices

The user can no longer open the feed details page multiple times (Soumyadeep Ghosh, 24.12.0, link).

Falkon Web Browser

It is now possible to open a context menu with Greasemonkey (Juraj Oravec, 24.12.0, link). Greasemonkey you to run little scripts that make on-the-fly changes to web page content. Juraj also removed the advertised FTP support in Falkon as the support for FTP was removed from Chromium. (Juraj Oravec, 24.12.0, link)

Dolphin Manage your files

We no longer ask password twice when entering the Dolphin's admin mode (kio-admin) (Felix Ernst, 24.12.0, link).

Felix also improved the keyboard navigation in the toolbar, now the elements are focused in the right order (Felix Ernst, 24.12.0. link 1 and link 2).

KDE Itinerary Digital travel assistant

Itinerary can now show you a map of the whole trip (Volker Krause, 24.12.0, link).

And display some statistics about your trip, for example the CO2 emission, the distance travelled and the costs (if available) (Volker Krause, 24.12.0, link).

Finally, the alignment of timeline elements in Itinerary is now much more consistent (Carl Schwan, 24.12.0, link).

Okular View and annotate documents

When loading PDF files with Ink annotation containing an empty path, Okular won't crash. You shouldn't be able to create such annotations with Okular anyway, but some PDF files out there do contains such annotations (Albert Astals Cid, 24.12.0, link).

We also no longer hide the signing UI prematurely and now ensure it is visible until the signing process is actually finished (Nicolas Fella, 24.12.0, link).

Finally we fixed a small memory leak in Okular's latex support (Nil Admirari, 24.12.0, link).

Kaffeine Multimedia Player

Kaffeine got ported to Qt6/KF6 (Tobias Klausmann, 24.12.0, link).

Calculator A feature rich calculator

Kalk will now correctly handle pressing the Esc key and clear the input field like many other calculator applications do, instead of creating strange characters in the input area (Devin Lin, 24.12.0, link).

Kasts Podcast application

Bart de Vries fixed password loading for synchronisation services on Windows (Bart De Vries, 24.12.0 link).

Kate Advanced Text Editor

The performance of displaying the build output has been improved (Waqar Ahmed, 24.12.0 link).

KDevelop Featureful, plugin-extensible IDE for C/C++ and other programming languages

We addressed certain annoyances when working with the flatpak runtime. This included, for example, improving the handling of .flatpak-manifest.json files which we use in KDE for storing the an application's Flatpak manifest (Aleix Pol Gonzalez, 24.12.0 link).

KMail A feature-rich email application

KMail and other PIM applications can now be compiled on Windows (Ingo Klöcker and Laurent Montel link 1 and link 2). Having KDE PIM applications work well on Windows is still in early stages of development. There is still a lot of work required to make Kontact a good experienceon that platform.

KMix Sound Mixer

KMix got ported to Qt6/KF6 (Jonathan Marten, 24.12.0 link).

Krita Digital Painting, Creative Freedom

SVGs with clip masks now render faster (Dmitry Kazakov, link).

Konsole Use the command line interface

Konsole now always creates a cgroup hierarchy when creating new process. This prevents entire applications getting killed in an Out-Of-Memory (OOM) scenarios when a tab consumes too much RAM (David Redondo, 24.12.0, link). David also ensured the subprocess of Konsole are correctly mapped to Konsole's .desktop file (link).

Kwave Sound editor

KWave now provides a better visual indication when playback is paused (Mark Penner, 24.12.0, link).

NeoChat Chat on Matrix

We improved the network proxy's config page look to make it more consistent with the other config pages (Joshua Goins, 24.12.0, link).

Joshua Goins and Olivier Beard improved the link preview. Now clicking anywhere on the link preview will take you to the linked webpage (Joshua Goins, 24.12.0, link). The separator shown to the left of the preview and quoted text also got stylish rounded corners (Olivier Beard, 24.12.0, link).

NeoChat now hides non-standard rooms from the room list as most of the time they are used exclusively for holding data (e.g. trip group information from Itinerary) and not meant to be interacted with (Joshua Goins, 24.12.0, link).

We also improved the way polls look (Carl Schwan, 24.12.0, link).

And made sending messages and inserting newline shortcuts configurable (Eren Karakas, 24.12.0, link).

Tokodon Browse the Fediverse

Right clicking on a link on a post will now show a context menu allowing users to copy or share the URL directly (Arran Ubels, 24.12.0, link).

And all this too...

The layout of the About dialog of applications using QtWidgets has been improved (Carl Schwan, KDE Frameworks 6.10.0, link).

Before After ... And Everything Else

This blog only covers the tip of the iceberg! If you’re hungry for more, check out Nate's blog about Plasma and be sure not to miss his This Week in Plasma series, where every Saturday he covers all the work being put into KDE's Plasma desktop environment.

For a complete overview of what's going on, visit KDE's Planet, where you can find all KDE news unfiltered directly from our contributors.

Get Involved

The KDE organization has become important in the world, and your time and contributions have helped us get there. As we grow, we're going to need your support for KDE to become sustainable.

You can help KDE by becoming an active community member and getting involved. Each contributor makes a huge difference in KDE — you are not a number or a cog in a machine! You don’t have to be a programmer either. There are many things you can do: you can help hunt and confirm bugs, even maybe solve them; contribute designs for wallpapers, web pages, icons and app interfaces; translate messages and menu items into your own language; promote KDE in your local community; and a ton more things.

You can also help us by donating. Any monetary contribution, however small, will help us cover operational costs, salaries, travel expenses for contributors and in general just keep KDE bringing Free Software to the world.

To get your application mentioned here, please ping us in invent or in Matrix.

We've released a new video! ..Templates! you can create them with Krita to save time in your digital paintings and be more focused on your artwork. They are seamless, they are useful, and they are really easy to generate. So let´s go with another supercool feature of Krita.

Check out the video for download links for the templates themselves!

Here's our bi-monthly update from KDE's personal information management applications team. This report covers progress made in September and October 2024.

Since the last report, 24 people have contributed over 1100 changes to the KDE PIM code base. We also released a two bugfix releases of the KDE PIM Suite with the Gear releases 24.08.1 and 24.08.2

Please note this is the last bi-monthly blog post for KDE PIM. We will continue to work on KDE PIM but weekly improvements to KDE PIM are now included in the This Week in KDE Apps blog.

Akademy

The KDE PIM team was at Akademy from the 7th to the 12th of September in Würzburg (Germany). We hosted again a PIM BoF.

We covered a few topics and made plans. In particular we touched upon contributions blockers, we hope the milestone system will help and also working on the amount of repositories which are not part of KDE Frameworks. Things are progressing in the right direction but slowly. Feel free to reach out to help!

Milestones

Talking about the milestones. You can see what we got in store on the Gitlab board. Some of them are progressing nicely like the resurrection of Kontact for Windows or the port away from QCA.

If you see anything you fancy and you would like to help, reach out to us on the #kontact:kde.org Matrix channel!

Applications Itinerary

Our travel assistance app Itinerary got a new two-level trip/timeline view, an extended public transport location search, a new full trip map view and better Android platform integration. Read more in [its own bi-monthly update] (https://volkerkrause.eu/2024/10/03/kde-itinerary-august-september-2024.html).

KAlarm

David has been working on fixing bugs around sound handling. In particular, repeating audio alarms only playing once have been fixed. Likewise the failure to play sound files using libVLC on some systems is gone. Also the backend to play sound can be changed at build time, it can use VLC or MPV.

But that's not the only bugs which got squashed. It's now possible to wake from suspend when using RTC wake and a crash has been fixed affecting systems where the kernel supports alarm timers.

Last but not least, the GUI has been improved around the run mode options in the preferences dialog.

Merkuro

Claudio has been busy fixing regressions and improving the stability of Merkuro. Notably, maps are now displayed again (if the event contains coordinates). Also, the collection combobox in the editors are now initialized with a valid collection and filtering features have been repaired.

KAddressBook and KOrganizer

The general improvements to support Plasma Activities is still on going. It is not enabled by default as it requires Akonadi Resources support to become really useful and the corresponding changes are not there yet.

KMail

On the KMail front the search has been greatly improved. There is now a custom syntax usable in the search text field. One can now use keywords like subject:, body:, to, from, has:attachment, is:important, is:replied and so on to make more precise queries.

For instance one could write "from:vkrause@kde.org to:kde-pim@kde.org is:important" to get only the emails from Volker on the kde-pim mailing list which are also flagged as important.

As you may know, Fedora KDE 41 was released a couple of weeks ago.

I wanted to talk about a special feature that our colleague @farchord (with support from upstream developer @Nate Graham) has brought to our Fedora KDE distribution:

Enabling Third Party Repositories With A Single Click!

Thanks to the flexibility of plasma-welcome we can offer this feature

Right after installing Fedora and on first login you will be presented with the Plasma Welcome window:

Before you click on Skip , you can go through the different slides to read about KDE and Fedora and also to decide whether you want to contribute with anonymous metrics or not (note: I personally do not):

Here is where the interesting part comes in, on the next slide:

With a simple click of a button you will enable the most commonly requested by our users Third Party Repositories like rpmfusion! (note: you will be asked for your administrator password)

Once the request is processed, the message will change to:

That’s it! You have successfully enabled Third Party Repositories without needing to modify any file or running any command whatsoever

Before you do anything with your system and your new configuration, I will strongly recommend to update your system via Plasma Discover :

Proceed with all the update and reboot to get the latest and shiniest from our repositories.

Finally, to verify that the Third Party software is available, you can check:

And that is it!

Enjoy!

This is all thanks to farchord, siosm , aleasto and ngraham‘s work!

Has this ever occurred to you? The most joyful moments of your life got filled with sorrow, a grief of loss…

Let’s talk about the Ubuntu Summit first, my international conference and solo travel outside my country. Probably I am the first from my entire extended family to visit a European country. My parents, well-wishers everyone was so happy. Only person didn’t know much about this, my maternal grandfather, whom I called (yes, “called”, he left us on 27th October 2024) Dada. Let me tell you about the summit first.

This week was full of major feature work and UI polishing, in addition to a lot of bug-fixing! I'm pretty sure everyone will find something to be excited about here:

Notable New Features

You can now swap the functions of drawing tablet pen buttons if you like the function performed by one of the buttons, but not which button activates it. (Joshua Goins, 6.3.0. Link)

Info Center now shows all of your GPUs, not just one of them. And they are now indicated in a fancy way! (Harald Sitter, 6.3.0. Link 1 and link 2)

Discover now shows you when apps are either packaged directly by their developer, or verified by a trusted third party. (Aleix Pol Gonzalez, 6.3.0. Link)

The Printers widget now shows each printer's print queue inline, right there in the widget! (Kai Uwe Broulik, 6.3.0. Link)

The Task Manager widget now lets you configure whether the "I'm playing audio" icons that appear in the corner of tasks can be clicked to mute the audio. In addition, the audio controls now always appear in the window preview thumbnails, and can't be accidentally disabled. (Petar Margetic, 6.3.0. Link)

When you've set up your system to reboot into the bootloader menu the next time it reboots (and not the firmware screen; that case was already handled), the logout screen how indicates this. (Nikolay Kochulin, 6.3.0. Link)

Notable UI Improvements

When you put a pie chart style System Monitor widget on a really skinny panel, the percentage circle in the center now looks nice, rather than being jagged and overly bold. (Arjen Hiemstra, 6.2.4. Link)

Made the progress indicators on Discover's Updates page more readable. (Nate Graham, 6.2.4. Link)

The Keyboard Indicator widget now indicates when modifier keys are "latched" or "locked", as they can be when using certain accessibility settings. (Nicolas Fella, 6.3.0. Link)

Removed the "Settings" launcher menu category! Now all of its contents have been moved into the "System" category. This reduces the number of categories that don't offer meaningful grouping. (Nate Graham, 6.3.0. Link)

The Printers widget now shows a little busy spinner for any printers that are currently printing, to make them easier to pick out among others when there are a lot of printers available. (Kai Uwe Broulik. 6.3.0. Link)

Widgets placed on the desktop are now very slightly translucent, just like the popups of widgets placed on the panel. (Marco Martin, 6.3.0. Link)

When for some reason the system time zone is set incorrectly or not set at all, the Digital Clock widget now tells you what's going on and offers you the chance to fix it yourself instead of just being broken. (Niccolò Venerandi, 6.3.0. Link)

Added a distinct Breeze icon for System Settings' Shortcuts page. (Joshua Goins, Frameworks 6.9. Link)

Improved the Breeze icon shown on password dialogs. (Kai Uwe Broulik, Frameworks 6.9. Link)

Notable Bug Fixes

Fixed a case where KWin would crash when plugging in external screens. (Xaver Hugl, 6.2.3. Link)

Fixed a regression caused by a version 0.22 of the power-profiles-daemon service that caused power profiles to not be registered properly by Plasma's Power and Battery widget until you manually restarted the Powerdevil service. (Méven Car, 6.2.3. Link)

Discover's auto-update feature once again works for Flatpak apps. (Harald Sitter, 6.2.4. Link)

The speaker test window on System Settings' Audio page now always fits its content, no matter what the name of the device or its audio profile may be. (Ismael Asensio, 6.2.4. Link)

Fixed a strange issue that would make GTK 4 apps look too dark when using HDR mode. Now they're a bit too light, but this is a GTK 4 bug. (Xaver Hugl, 6.2.4. Link)

Plasma panels in "fit content" mode are now compatible with flexible spacers; placing one on a panel no longer causes it to slowly grow to its full width when Plasma starts up — which was hilarious, but wrong. (Niccolò Venerandi, 6.2.4. Link)

Fixed a small visual glitch in KWin's Overview effect that caused windows dragged-and-dropped onto the desktop bar to strangely glide off screen. (Marco Martin, 6.2.4. Link)

Did a major code refactor and bug-fixing spree for desktop icon positioning, which fixes almost all of the outstanding bug reports about icons moving around, and also adds autotests to validate the fixes! You can read more about it here, too. (Akseli Lahtinen, 6.3.0. Link)

Alt key accelerators for items in the Global Menu widget now work on Wayland. (Nicolas Fella, 6.3.0. Link)

Performing a major system update using Discover no longer makes a pointless and invisible authentication prompt appear behind the logout window when you try to reboot to complete the update. (Alessandro Astone, PackageKit 1.3.1. Link)

Other bug information of note:

• 4 Very high priority Plasma bug (same as last week). Current list of bugs
• 37 15-minute Plasma bugs (down from 40 last week). Current list of bugs
• 106 KDE bugs of all kinds fixed over the last week. Full list of bugs

Notable in Performance & Technical

The feature to let you record the screen without re-approval if it's the same as one you did last time now also works when using rectangular region recordings. (David Redondo, 6.3.0. Link)

Implemented support for the Wayland system bell protocol. (David Redondo, 6.3.0. Link)

How You Can Help

KDE has become important in the world, and your time and contributions have helped us get there. As we grow, we need your support to keep KDE sustainable.

You can help KDE by becoming an active community member and getting involved somehow. Each contributor makes a huge difference in KDE — you are not a number or a cog in a machine!

You don’t have to be a programmer, either. Many other opportunities exist:

• Filter and confirm bug reports, maybe even identify their root cause
• Contribute designs for wallpapers, icons, and app interfaces
• Design and maintain websites
• Translate user interface text items into your own language
• Promote KDE in your local community
• …And a ton more things!

You can also help us by donating to our yearly fundraiser! Any monetary contribution — however small — will help us cover operational costs, salaries, travel expenses for contributors, and in general just keep KDE bringing Free Software to the world.

To get a new Plasma feature or a bugfix mentioned here, feel free to push a commit to the relevant merge request on invent.kde.org.

A few weeks ago Qt 6.8 was released, delivering many fixes and improvements for our software. Some of them were contributed by yours truly, and in this post I want to highlight some of them.

They relate to graphics tablet/stylus input on Wayland. Before we go into the fixes let’s have a quick overview of the flow of tablet input events on Wayland:

The genesis of input events is in the kernel driver for the particular tablet, which talks to the hardware (via USB, bluetooth etc). The kernel passes events to userspace via the evdev system. On the userspace side a Wayland compositor reads those events. Most compositors leverage libinput for this, a library that transforms raw evdev events into something more usable for the compositor while applying some cleaning and configuration. The compositor then delivers events to native Wayland applications using the tablet-v2 protocol. For legacy XWayland applications the compositor uses this protocol to send events to XWayland, which translates them into things X11 apps understand. The compositor can apply useful transformations to the input, like which area of the screen the tablet is mapped to, changing the pressure curve of the pen, or binding buttons to keyboard shortcuts.

The application then processes the events, potentially leveraging a UI toolkit like Qt. Qt creates QTabletEvent object for incoming Wayland events and delivers those to all UI elements. In case no UI element reacts to the event Qt will synthesize a mouse event from the tablet event and deliver that to the UI elements. That way most controls like buttons and menus don’t need special code to handle tablet input. Only when doing very low-level input handling or when needing tablet-specific interactions (like reacting to different pressure values) application developers need to explicitly handle tablet events in their code. Most UI toolkits will work somewhat similar to this. If an application doesn’t react to tablet input at all please file a bug against the application.

Qt Wayland had support for tablet input for a few years now, so what exactly needed fixing? The first thing is cursors. In Wayland the application tells the compositor which cursor to use. This can be done either by specifying a surface (i.e. an image) or a named cursor shape. Guess which one Qt used? That’s right: Neither. It just didn’t specify a cursor at all. The result depends on the compositor: KWin would display a cross-hair cursor as a fallback, which is ~okay, but not the cursor the application developer asked for. On other compositors I’ve tested there will be no cursor visible at all, which isn’t okay at all. For Qt 6.8 I implemented the missing cursor support, so now tablets get the same cursor as mouse input (unless of course the application developer wants a different cursor for tablet input).

Another thing that affected mostly non-Plasma users is client-side decorated windows. On Plasma Qt applications usually use the server-side decoration provided by KWin, but e.g. on GNOME Qt is responsible for drawing and handling window decorations. For this Qt features a plugin system so different decorations with different look-and-feels can be swapped out. Unfortunately those decorations didn’t handle tablet input at all, so it wasn’t possible to move around or close windows using a tablet stylus. I fixed this by pretending the tablet input is mouse input to the decorations, which was a simple yet effective solution for the issue. If there is ever a need for decorations to treat tablet input different to mouse input we can revisit this.

Talking about moving windows, a feature most KDE apps have (even if off-by-default these days) is dragging any empty area to move the window. This wasn’t working when using a stylus. Why? For that we need to look at how this works on a Wayland level. The xdg-shell protocol (the one responsible for most application windows) has a move request that asks the compositor to start a move interaction for the window. As part of the request the application must pass a serial, which is a number that corresponds to the last input event the application has received. To avoid applications suddenly deciding to move in the background compositors usually only allow move requests as a result of direct user input, so this serial must match the last input event. Qt wraps this move request inside the QWindow::startSystemMove function. The problem was that Qt didn’t keep track of the serial it received as part of tablet input, so when starting the move it would pass a wrong serial and the compositor (rightfully) refused the move. A few extra lines later the serial was tracked properly and moving windows with a stylus worked, just in time for Nate to disable the feature by default.

The same problem also affected drag-and-drop. When starting a drag with a stylus Qt now passes the correct serial, making drag-and-drop work (at least on the Qt side, there currently is a bug on the KWin side that prevents this from working).

The last fix for today relates to how applications react to the tablet events. Sometimes applications process clicks differently depending on what keyboard modifiers are pressed. For example pressing Ctrl while clicking on files in Dolphin allows to select multiple files. For this to work Qt conveniently delivers the active modifiers with every input event. Alas for tablet input the modifiers got lost along the way, so it wasn’t possible to select multiple files using a stylus. One small fix later it works as expected.

That’s all the Wayland tablet related fixes for today. If you find more issues in Qt/KDE apps related to tablet input on Wayland please report them on bugs.kde.org and I’ll look into them.

That’s not all there is about Wayland tablet improvements though. Fully in the spirit of the “We care about your input!” Goal there are exiting things happening on the KWin/Plasma side that I’ve been involved in. Stay tuned for more!

In my position of Software Platform Engineer at KDE I work on common building blocks for KDE software, like Qt and KDE Frameworks. This work is possible thanks to your generous donations. Check out our end-of-the-year fundraiser if you’d like to see more work like this.