FLOSS Project Planets

USB-A is the original socket for USB at the PC end. There are 2 variants of it, the first is for USB 1.1 to USB 2 and the second is for USB 3 which adds extra pins in a plug and socket compatible manner – you can plug a USB-A device into a USB-A socket without worrying about the speeds of each end as long as you don’t need USB 3 speeds.

The differences between USB-A and USB-C are:

1. USB-C has the same form factor as Thunderbolt and the Thunderbolt protocol can run over it if both ends support it.
2. USB-C generally supports higher power modes for charging (like 130W for Dell laptops, monitors, and plugpacks) but there’s no technical reason why USB-A couldn’t do it. You can buy chargers that do 60W over USB-A which could power one of our laptops via a USB-A to USB-C cable. So high power USB-A is theoretically possible but generally you won’t see it.
3. USB-C has “DisplayPort alternate mode” which means using some of the wires for DisplayPort.
4. USB-C is more likely to support the highest speeds than USB-A sockets for “super speed” etc. This is not a difference in the standards just a choice made by manufacturers.

While USB-C tends to support higher power delivery modes in actual implementations for connecting to a PC the PC end seems to only support lower power modes regardless of port. I think it would be really good if workstations could connect to monitors via USB-C and provide power, DisplayPort, and keyboard, mouse, etc over the same connection. But unfortunately the PC and monitor ends don’t appear to support such things.

If you don’t need any of those benefits in the list above (IE you are using USB for almost anything we do other than connecting a laptop to a dock/monitor/charger) then USB-A will do the job just as well as USB-C. The choice of which type to use should be based on price and which ports are available, EG My laptop has 2*USB-C ports and 2*USB-A so given that one USB-C port is almost always used for the monitor or for charging I don’t really want to use USB-C for anything else to avoid running out of ports.

When buying USB devices you can’t always predict which systems you will need to connect them to. Currently there are a lot of systems without USB-C that are working well and have no need to be replaced. I haven’t yet seen a system where the majority of ports are USB-C but that will probably happen in the next few years. Maybe in 2027 there will be PCs on sale with only two USB-A sockets forcing people who don’t want to use a USB hub to save both of them for keyboard and mouse. Currently USB-C keyboards and mice are available on AliExpress but they are expensive and I haven’t seen them in Australian stores. Most computer users don’t wear out keyboards or mice so a lot of USB-A keyboard and mice will be in service for a long time. As an aside there are still many PCs with PS/2 keyboard and mouse ports in service so these things don’t go away for a long time.

There is one corner case where USB-C is convenient which is when you want to connect a mass storage device for system recovery or emergency backup, want a high speed, and don’t want to spend time figuring out which of the ports are “super speed” (which can be difficult at the back of a PC with poor lighting). With USB-C you can expect a speed of at least 5Gbit/s and don’t have to worry about accidentally connecting to a USB 2 port as is the situation with USB-A.

For my own use the only times that I prefer USB-C over USB-A are for devices to connect to phones. Eventually I’ll get a laptop that only has USB-C ports and this will change, but even then adaptors are possible.

For someone who doesn’t know the details of how things works it’s not unreasonable to just buy the newest stuff and assume it’s better as it usually is. But hopefully blog posts like this can help people make more informed decisions.

Related posts:

1. Dell 32″ 4K Monitor and DisplayPort Switch After determining that the Philips 43″ monitor was too large...
2. Cheap Peripherals for Work A problem with a lot of the purchase of peripherals...
3. Thinkpad X1 Carbon Gen 6 In February I reviewed a Thinkpad X1 Carbon Gen 1...

Some time ago I quickly wrote a little utility to render XRechnung documents on the free desktop, called XRView. This is the initial Bogpost. It was a very fundamental Qt Widget app that shows e-invoice docs that come in the XRechnung XML format, in a human readable view.

It was never properly released, so recently I decided to wrap it up and finally cut a first release which people can find on the release page on Codeberg.

Technically it uses the XSLT stylesheets provided by Kosit and calls an external java process on the local machine to run that through a specific Saxon processor. For that, XRView requires a java runtime installed.

Since the setup of these dependencies is a bit cumbersome, the new release 1.0 does that for users. It downloads the stylesheets and also the saxon processor runtime from their upstream repositories and stores them on the local machine for future use. Of course it is strongly recommended to double check the downloaded resources for their validity and integrity and not to run software that some other code downloaded.

More new features in this first release are:

• internationalization, first available language is German
• a rudimentary application menu with about dialog and such
• the setup routine as described above

Note that this is the first release of the software. Yet, I think it is useful, and a interesting starting point for further activities in this area. As XRechnung will become a mandatory standard for all companies in Germany (at least) I think it is very important to have a free software alternative. There are already many commercial offerings.

However, I am not feeling to develop and maintain this as an “one man show” forever. Being kind of frustrated about the way how free software is often consumed nowadays, I will happily continue to contribute to it if there is more interest than “gimme for free” by other people or organizations.

Let’s see if this is heading somewhere :-)

Since phoc 0.39.0 it is possible to configure which keys unidle your phone (which results in unblanking the screen). The current default is that all keys unblank which is usually fine for e.g. laptops but not the desired result for phones and tablets where this depends on the position and function of keys. Volume keys and other exposed keys usually shouldn’t unblank - maybe with the exception of some Home buttons on devices that have those.

So you've created a web app with Python using Flask, Django, FastAPI, or even Emmett. It works great on your machine. How do you get it out to the world? You'll need a production-ready web server. On this episode, we have Giovanni Barillari to tell us about his relatively-new server named Granian. It promises better performance and much better consistency than many of the more well known ones today.<br/> <br/> <strong>Episode sponsors</strong><br/> <br/> <a href='https://talkpython.fm/neo4j-graphstuff'>Neo4j</a><br> <a href='https://talkpython.fm/training'>Talk Python Courses</a><br/> <br/> <strong>Links from the show</strong><br/> <br/> <div><b>New spaCy course</b>: <a href="https://training.talkpython.fm/courses/getting-started-with-spacy" target="_blank" rel="noopener">talkpython.fm</a><br/> <br/> <b>Giovanni</b>: <a href="https://twitter.com/gi0baro" target="_blank" rel="noopener">@gi0baro</a><br/> <b>Granian</b>: <a href="https://github.com/emmett-framework/granian" target="_blank" rel="noopener">github.com</a><br/> <b>Emmett</b>: <a href="https://emmett.sh" target="_blank" rel="noopener">emmett.sh</a><br/> <b>Renoir</b>: <a href="https://github.com/emmett-framework/renoir" target="_blank" rel="noopener">github.com</a><br/> <b>Watch this episode on YouTube</b>: <a href="https://www.youtube.com/watch?v=KwqO7KVEpxs" target="_blank" rel="noopener">youtube.com</a><br/> <b>Episode transcripts</b>: <a href="https://talkpython.fm/episodes/transcript/463/running-on-rust-granian-web-server" target="_blank" rel="noopener">talkpython.fm</a><br/> <br/> <b>--- Stay in touch with us ---</b><br/> <b>Subscribe to us on YouTube</b>: <a href="https://talkpython.fm/youtube" target="_blank" rel="noopener">youtube.com</a><br/> <b>Follow Talk Python on Mastodon</b>: <a href="https://fosstodon.org/web/@talkpython" target="_blank" rel="noopener"><i class="fa-brands fa-mastodon"></i>talkpython</a><br/> <b>Follow Michael on Mastodon</b>: <a href="https://fosstodon.org/web/@mkennedy" target="_blank" rel="noopener"><i class="fa-brands fa-mastodon"></i>mkennedy</a><br/></div>

We just branched for Plasma 6.1 and released the beta, which means the window to add new features has now closed. But before it did, a ton of amazing stuff snuck in! Plasma 6.1 promises to be a large and impressive release.

Probably the most impactful thing is triple buffering support on Wayland! This should make animations and screen rendering smoother in general–ideally up to the level of the X11 session, which already did triple buffering. This work by Xaver Hugl has been in progress for a long time and lands in Plasma 6.1. Link

That’s not all though… oh no, not by a long shot:

New Features

Dolphin now includes a feature to move the selected items into a new folder, all at once (Ahmet Hakan Çelik, Dolphin 24.08. Link)

KDE’s desktop portal implementation now includes support for the Input Capture portal (David Redondo, Plasma 6.1. Link 1, link 2, and link 3)

Plasma now supports enabling and disabling the feature of some Lenovo IdeaPad and Legion laptops whereby the battery can be configured to only charge up to a specific fixed level (sometimes 60%, sometimes 80%; it depends on the machine) to maximize battery health (Fabian Arndt, Plasma 6.1. Link)

Plasma’s Edit Mode has a beautiful new zoom-out effect to help you notice and understand you’re in a separate mode, and also make it easier to get out once you’re done (Marco Martin, Plasma 6.1. Link 1 and link 2):

https://i.imgur.com/EryNKTq.mp4

You can now configure the screen locker to unlock without a password, letting it be used as a traditional screensaver if you enable a visually attractive wallpaper plugin and disable the clock (Kristen McWilliam, Plasma 6.1. Link)

UI Improvements

Our long national nightmare of jarring error beep sounds is now over!!!! Plasma now intercepts attempts to ring the system bell (which generally sounds so unpleasant that you feel the need to immediately commit an act of violence) and replaces them with a nice sound from the active sound theme (Nicolas Fella, Plasma 6.1. Link 1, link 2, and link 3)

KRunner search results already prioritized apps by default, but now they also prioritize System Settings pages too (Alexander Lohnau, Plasma 6.1, link 1, and link 2)

On System Settings’ Power Management page, a few UI controls that used spinboxes have been replaced with fancy comboboxes. This fixes some bugs and offers a faster interaction paradigm for the basic use case of choosing a common value — with an expert workflow of letting you select anything you want in a dialog box (Jakob Petsovits, Plasma 6.1. Link):

https://i.imgur.com/2YISTOz.mp4

System Settings’ Printers page now guides you through the process of installing the system-config-printer package to improve printer detection, if it wasn’t pre-installed by your distro (Mike Noe, Plasma 6.1. Link)

Getting information from weather providers can sometimes be a bit flaky, so Plasma’s Weather Report widget now informs you to just try again in a little bit when this happens (me: Nate Graham, Plasma 6.1. Link):

The way Welcome Center presents KRunner has gotten a major overhaul, and now shows a fancy animated depiction of actually using it! In addition, the final page is now more streamlined and less demanding of your time and money (Oliver Beard, Plasma 6.1. Link 1 and link 2):

Plasma’s Weather Widget no longer shows the “Appearance” page in its config window when used on the desktop, since nothing on that page is applicable to the desktop form factor (Ismael Asensio, Plasma 6.1. Link)

KWin’s custom tile editor now uses clearer terminology for creating split views (me: Nate Graham, Plasma 6.1. Link):

System Settings’ Background Services page is no longer actually visible in System Settings by default; everything here is an implementation detail, and monkeying with its settings is an easy way to break your system. If you’re an expert, you can still get to it by searching for it in KRunner, but it won’t be shown in System Settings anymore (Nicolas Fella, Plasma 6.1. Link)

The remainder of the header messages in System Settings pages have been ported to the new frameless style, making them all consistent now (me: Nate Graham, Plasma 6.2. Link):

Improved the way SVG images render on screen when using a fractional scale factor, reducing blurriness (Marco Martin, Frameworks 6.3. Link)

Bug Fixes

Filelight no longer counts files stored in OneDrive cloud as local files that occupy space (Harald Sitter, Filelight 24.05.1. Link)

In KColorChooser, the “Pick Screen Color” button is no longer missing on Wayland (Thomas Weißschuh, KColorChooser 24.05.1. Link)

Made Plasma more robust against crashing when any widgets have malformed size values, which can happen under certain circumstances (Marco Martin, Plasma 6.0.5. Link)

When KWin falls back to using a software cursor after the graphics driver rejected the use of a hardware cursor, this can no longer lock up the entire screen under certain circumstances — such as with XWayland-using apps on an Apple Silicon Mac (Xaver Hugl, Plasma 6.0.5. Link)

Spectacle no longer takes blurry screenshots on systems with multi-screen plus mixed-scale-factor setups (Volodymyr Zolotopupov, Plasma 6.0.5. Link)

Global shortcuts are now more robust and stable on NixOS and other distros that regenerate the sycoca cache repeatedly in an automated manner (Vlad Zahorodnii, Plasma 6.0.5. Link)

Fixed multiple longstanding issues in System Settings whereby switching pages, clearing the search field, or opening a new page form outside of System Settings would cause the sub-category column to show the wrong thing (Nicolas Fella, Plasma 6.0.5. Link 1, link 2, and link 3)

Fixed a case where turning off an external monitor plugged into a laptop with its lid closed could cause KWin to crash (Xaver Hugl, Plasma 6.1. Link)

On Wayland, Plasma no longer quits when you open an enormous number of windows (Xaver Hugl, Plasma 6.1. Link)

The “Activation Gestures” category of System Settings’ Accessibility page is back, after being accidentally removed when the page was ported to QML (Nicolas Fella, Plasma 6.1. Link)

On Wayland, when any apps that have System Tray icons are running, there’s no longer a little invisible square in the top-left corner of the screen that eats input, and also no elevated CPU usage with certain screen arrangements (David Edmundson, Plasma 6.1. Link 1 and link 2)

Pressing Meta+B repeatedly no longer opens multiple Power Profile chooser OSDs, and therefore no longer represents a way for you to exhaust your system’s memory by generating an infinite stack of them (Fabian Arndt, Plasma 6.1. Link)

Made KWin more reliable about detecting screens’ physical sizes (Jakub Piecuch, Plasma 6.1. Link)

When using a Plasma Panel in “Fit content” mode with only an Icons-Only Task Manager on it, there’s no longer unnecessary empty space on the right side of it on login (Akseli Lahtinen, Plasma 6.1. Link)

In the dialog that lets you choose windows and screens to share, clicking on the checkboxes to select items now works. Previously you had to click on the whole items themselves, but the checkboxes didn’t work; now both work (me: Nate Graham, Frameworks 6.3. Link)

Fixed several issues preventing certain Breeze icons from adjusting their colors properly when run with a dark color scheme, as well as issues with generation of static dark-theme-compatible icons (Corbin Schwimmbeck, Frameworks 6.3. Link 1 and link 2)

Re-spun the KWidgetsAddons framework to include a bugfix for an issue that caused OBS to crash when selecting files, and also one that caused KMessageWidgets to sometimes show incorrect background colors (Joshua Goins and Albert Astals Cid, KWidgetsAddons frameworks 6.2.2. Link 1 and link 2)

Re-spun the KWallet framework to include a bugfix for an issue that caused the Secrets portal to not work in Flatpak apps (Nicolas Fella, KWallet 6.2.1. Link)

Context menus should now be a lot less likely to appear as odd standalone windows with titlebars when activated on an inactive window (Vlad Zahorodnii, Qt 6.7.2. Link)

Other bug information of note:

• 3 Very high priority Plasma bugs (same as last week). Current list of bugs
• 36 15-minute Plasma bugs (down from 39 last week). Current list of bugs
• 105 KDE bugs of all kinds fixed over the last week Full list of bugs

Performance & Technical

Reduced frame drop on a variety of hardware (Xaver Hugl, Plasma 6.1. Link)

Improved the speed with which Discover launches and how responsive it is when scrolling through long app lists while the Flatpak backend is active (Aleix Pol Gonzalez, Plasma 6.1. Link)

Automation & Systematization

Added some new autotests for Plasma panels and containments to make sure they get sized and located correctly (Marco Martin and Akseli Lahtinen. Link 1, link 2, and link 3)

…And Everything Else

This blog only covers the tip of the iceberg! If you’re hungry for more, check out https://planet.kde.org, where you can find more news from other KDE contributors.

How You Can Help

The KDE organization has become important in the world, and your time and labor have helped to bring it there! But as we grow, it’s going to be equally important that this stream of labor be made sustainable, which primarily means paying for it. Right now the vast majority of KDE runs on labor not paid for by KDE e.V. (the nonprofit foundation behind KDE, of which I am a board member), and that’s a problem. We’ve taken steps to change this with paid technical contractors — but those steps are small due to growing but still limited financial resources. If you’d like to help change that, consider donating today!

Otherwise, visit https://community.kde.org/Get_Involved to discover other ways to be part of a project that really matters. Each contributor makes a huge difference in KDE; you are not a number or a cog in a machine! You don’t have to already be a programmer, either. I wasn’t when I got started. Try it, you’ll like it! We don’t bite!

This post is a review for Computing Reviews for How computers make books • from graphics rendering, search algorithms, and functional programming to indexing and typesetting , a book published in Manning

If we look at the age-old process of creating books, how many different areas can a computer help us with? And how can each of them be used to teach computer science (CS) fundamentals to a nontechnical audience? This is the premise of John Whitington’s enticing book and the result is quite amazing.

The book immediately drew my attention when looking at the titles available for review. After all, my initiation into computing as a kid was learning the LaTeX typesetting system while my father worked on his first book on scientific language and typography [1]. Whitington picks 11 different technical aspects of book production, from how dots of ink are transferred to a white page and how they are made into controllable, recognizable shapes, all the way to forming beautiful typefaces and the nuances of properly addressing white-space to present aesthetically pleasing paragraphs, building it all into specific formats aimed at different ends.

But if we dig beyond just the chapter titles, we will find a very interesting book on CS that, without ever using technical language or notation, presents aspects as varied as anti-aliasing, vector and raster images, character sets such as ASCII and Unicode, an introduction to programming, input methods for different writing systems, efficient encoding (compression) methods, both for text and images, lossless and lossy, and recursion and dithering methods. To my absolute surprise, while the author thankfully spared the reader the syntax usually associated with LISP-related languages, the programming examples clearly stem from the LISP school, presenting solutions based on tail recursion. Of course, it is no match for Donald Knuth’s classic book on this same topic [2], but could very well be a primer for readers to approach it.

The book is light and easy to read, and keeps a very informal, nontechnical tone throughout. My only complaint relates to reading it in PDF format; the topic of this book, and the care with which the images were provided by the author, warrant high resolution. The included images are not only decorative but an integral part of the book. Maybe this is specific to my review copy, but all of the raster images were in very low resolution.

This book is quite different from what readers may usually expect, as it introduces several significant topics in the field. CS professors will enjoy it, of course, but also readers with a humanities background, students new to the field, or even those who are just interested in learning a bit more.

References

1. Sánchez y Gándara, A.; Magariños Lamas, F.; Wolf, K. B., Manual de lenguaje y tipografía científica en castellano. Trillas, Mexico City, Mexico, 1986, https://www.fis.unam.mx/~bwolf/manual.html

2. Knuth, D. E. Digital typographyCSLI Lecture Notes: CSLI Lecture Notes. CSLI Publications, Stanford, CA, 1999, https://www-cs-faculty.stanford.edu/~knuth/dt.html

This article was updated in May 2024.

As a marketing leader, you need to drive traffic to your site and create a superior user experience. But you also need to push your content out to a variety of channels so you can reach your audience where they are.

To achieve your goals, you need a content management system (CMS) that’s flexible, scalable, and efficient. And if you’re researching your options, you’ve probably heard a lot about composable CMSs.

Every marketer and content editor deserves solutions that deliver outstanding results. Check how a preconfigured Drupal CMS can make your daily work easier!

In this quiz, you’ll test your understanding of how to create pivot tables with pandas.

By working through this quiz, you’ll review your knowledge of pivot tables and also expand beyond what you learned in the tutorial. For some of the questions, you’ll need to do some research outside of the tutorial itself.

[ Improve Your Python With 🐍 Python Tricks 💌 – Get a short & sweet Python Trick delivered to your inbox every couple of days. >> Click here to learn more and see examples ]

Let’s go for my web review for the week 2024-21.

Gender bias in open source: Pull request acceptance of women versus men

Tags: tech, foss, bias

A bit too GitHub centric for my taste. Still it shows some unwarranted bias, especially when outsiders to a project are identified as women. We should do better.

https://www.researchgate.net/publication/308716997_Gender_bias_in_open_source_Pull_request_acceptance_of_women_versus_men

BitKeeper, Linux, and licensing disputes: How Linus wrote Git in 14 days

Tags: tech, foss, version-control, linux, git, history

The often forgotten history behind the creation of Git. This article does a good job summarizing it.

https://graphite.dev/blog/bitkeeper-linux-story-of-git-creation

Pluralistic: The Coprophagic AI crisis

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

The training dataset crisis is looming in the case of large language models. They’ll sooner or later run out of genuine content to use… and the generated toxic waste will end up in training data, probably leading to dismal results.

https://pluralistic.net/2024/03/14/inhuman-centipede/#enshittibottification

Google Is Paying Reddit $60 Million for Fucksmith to Tell Its Users to Eat Glue

Tags: tech, ai, machine-learning, gpt, google, data, quality

No, your model won’t get smarter just by throwing more training data at it… on the contrary.

https://www.404media.co/google-is-paying-reddit-60-million-for-fucksmith-to-tell-its-users-to-eat-glue/

How DeviantArt died: A.I. and greed turned a once-thriving community into a ghost town.

Tags: tech, ai, machine-learning, art, social-media, criticism

This is indeed sad to see another platform turn against its users. This was once a place to nurture young artists… it’s now another ad driven platform full of AI made scams.

https://slate.com/technology/2024/05/deviantart-what-happened-ai-decline-lawsuit-stability.html

OpenAI departures: Why can’t former employees talk, but the new ChatGPT release can? - Vox

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

Open is unsurprisingly only in the name… this company is really just a cult.

https://www.vox.com/future-perfect/2024/5/17/24158478/openai-departures-sam-altman-employees-chatgpt-release

New Windows AI feature records everything you’ve done on your PC | Ars Technica

Tags: tech, microsoft, windows, security, privacy

This is completely nuts… they really want to unleash a security and privacy nightmare. The irony is that it does respect DRM content on the other hand, we can see where the priorities are.

https://arstechnica.com/gadgets/2024/05/microsofts-new-recall-feature-will-record-everything-you-do-on-your-pc/

A Grand Unified Theory of the AI Hype Cycle

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

Definitely this, it’s not the first time we see such a hype cycle around “AI”. When it bursts the technology which created it is just not called “AI” anymore. I wonder how long this one will last though.

https://blog.glyph.im/2024/05/grand-unified-ai-hype.html

A Plea for Sober AI | Drew Breunig

Tags: tech, ai, machine-learning, gpt, hype, criticism

Definitely too much hype around large models right now. This over shadows the more useful specialized models.

https://www.dbreunig.com/2024/05/16/sober-ai.html

Bing outage shows just how little competition Google search really has | Ars Technica

Tags: tech, google, microsoft, web, search

We’re still fairly dependent on just two major web indices… time for an index built as a common for everyone to use?

https://arstechnica.com/gadgets/2024/05/bing-outage-shows-just-how-little-competition-google-search-really-has/

stract: web search done right

Tags: tech, web, search

Looks like an interesting new search engine.

https://github.com/StractOrg/stract?tab=readme-ov-file

The curious case of the missing period - Tjaart’s Substack

Tags: tech, email, debugging

Fascinating bug… the fine details of mundane protocols like SMTP can sometimes be surprising.

https://tjaart.substack.com/p/the-curious-case-of-the-missing-period

Firefox bookmark keywords for faster navigation

Tags: tech, firefox, bookmarks

Interesting Firefox feature I didn’t notice. Looks fairly nice, I’ll use it more.

https://blog.meain.io/2024/firefox-bookmark-keywords

CADmium: A Local-First CAD Program Built for the Browser

Tags: tech, web, frontend, cad, physics, mathematics

This gives a good idea of the important parts in a CAD program. It also list a few of the usable libraries to build one such program in the browser.

https://mattferraro.dev/posts/cadmium

WebAssembly: A promising technology that is quietly being sabotaged

Tags: tech, webassembly, server

Where WebAssembly is, and where WebAssembly on the server is going… let’s hope it doesn’t become another CORBA.

https://kerkour.com/webassembly-wasi-preview2

Hartwork Blog · Clone arbitrary single Git commit

Tags: tech, git, ci

Neat trick, especially useful for CI uses.

https://blog.hartwork.org/posts/clone-arbitrary-single-git-commit/

Writing commit messages

Tags: tech, version-control, writing, communication

Very extensive guide on writing better commit messages. This is important, it’s a very central communication mechanism with other developers.

https://www.chiark.greenend.org.uk/~sgtatham/quasiblog/commit-messages/

UI Density || Matthew Ström, designer-leader

Tags: tech, gui, ux

Interesting discussion about UI density. What are we talking about? Is there value to is? Which aspects of a UI are impacting it? The conclusion makes it all very clear.

https://matthewstrom.com/writing/ui-density/

Bye for now!

KDDockWidgets has launched its latest version 2.1. This release comes packed with over 500 commits, offering enhanced stability over its predecessor, version 2.0, without introducing any breaking changes.

KDDockWidgets is a versatile framework for custom-tailored docking systems in Qt written by KDAB’s Sérgio Martins. For more information about its rich set of features, have a look at its GitHub repository.

What’s changed in version 2.1?

Here are the main highlights:

Bug Fixes:

For starters, KDDW 2.1 introduces a range of bug fixes aimed at enhancing stability and user experience. Less popular features like nested main-windows and auto-hide received lots of attention and window manager specific bugs such as restoring maximized windows were addressed.

KDDW is now memory-leak free, several singletons were leaking before. We’ve added a valgrind GitHub Actions workflow to prevent regressions regarding leaks.

QtQuick:

KDDW 2.1 also introduces improvements in QtQuick. New features include an API for setting affinities via QML, enabling mixing MDI with docking similar to QtWidgets, and fixing DPI issues of icons in TitleBar.qml for better scaling at 150% and 200%. Additionally, it resolves issues such as MDI widgets not raising when clicked on and various crashes related to MDI mode.

QtWidgets:

For QtWidgets, we’ve improved handling of the preferredSize argument when adding dock widgets. It was being ignored in some cases. Overriding DockWidget::closeEvent() can now be done to prevent closing. Several crashes were fixed and we’ve added a GitHub Actions workflow which runs the tests against a Qt built with AddressSanitizer.

These enhancements improve the functionality and stability of KDDW 2.1 across different Qt environments.

Miscellaneous:

KDDW 2.1 brings miscellaneous updates, including an upgrade to nlohmann json v3.11.3, the addition of a standalone layouting example using the UI toolkit Slint, and extensive testing on CI. Additionally, Config::setLayoutSpacing(int) has been added for increased customization.

Learn about all the changes here. Let us know what you think.

More information about KDDockWidgets

• • A manual on installation and usage written by KDAB’s Sérgio Martins.
  • Find out more about KDAB’s Qt tools.
  • A YouTube video about KDDockWidgets:

About KDAB

If you like this article and want to read similar material, consider subscribing via our RSS feed.

Subscribe to KDAB TV for similar informative short video content.

KDAB provides market leading software consulting and development services and training in Qt, C++ and 3D/OpenGL. Contact us.

The post KDDockWidgets 2.1 Released appeared first on KDAB.

In my previous blog, I explored The New APT 3.0 solver. Since then I have been at work in the test suite making tests pass and fixing some bugs.

You see for all intents and purposes, the new solver is a very stupid naive DPLL SAT solver (it just so happens we don’t actually have any pure literals in there). We can control it in a bunch of ways:

1. We can mark packages as “install” or “reject”
2. We can order actions/clauses. When backtracking the action that came later will be the first we try to backtrack on
3. We can order the choices of a dependency - we try them left to right.

This is about all that we really want to do, we can’t go if we reach a conflict, say “oh but this conflict was introduced by that upgrade, and it seems more important, so let’s not backtrack on the upgrade request but on this dependency instead.”.

This forces us to think about lowering the dependency problem into this form, such that not only do we get formally correct solutions, but also semantically correct ones. This is nice because we can apply a systematic way to approach the issue rather than introducing ad-hoc rules in the old solver which had a “which of these packages should I flip the opposite way to break the conflict” kind of thinking.

Now our test suite has a whole bunch of these semantics encoded in it, and I’m going to share some problems and ideas for how to solve them. I can’t wait to fix these and the error reporting and then turn it on in Ubuntu and later Debian (the defaults change is a post-trixie change, let’s be honest).

apt upgrade is hard

The apt upgrade commands implements a safe version of dist-upgrade that essentially calculates the dist-upgrade, and then undoes anything that would cause a package to be removed, but it (unlike its apt-get counterpart) allows the solver to install new packages.

Now, consider the following package is installed:

X Depends: A (= 1) | B

An upgrade from A=1 to A=2 is available. What should happen?

The classic solver would choose to remove X in a dist-upgrade, and then upgrade A, so it’s answer is quite clear: Keep back the upgrade of A.

The new solver however sees two possible solutions:

1. Install B to satisfy X Depends A (= 1) | B.
2. Keep back the upgrade of A

Which one does it pick? This depends on the order in which it sees the upgrade action for A and the dependency, as it will backjump chronologically. So

1. If it gets to the dependency first, it marks A=1 for install to satisfy A (= 1). Then it gets to the upgrade request, which is just A Depends A (= 2) | A (= 1) and sees it is satisfied already and is content.

2. If it gets to the upgrade request first, it marks A=2 for install to satisfy A (= 2). Then later it gets to X Depends: A (= 1) | B, sees that A (= 1) is not satisfiable, and picks B.

We have two ways to approach this issue:

1. We always order upgrade requests last, so they will be kept back in case of conflicting dependencies
2. We require that, for apt upgrade a currently satisfied dependency must be satisfied by currently installed packages, hence eliminating B as a choice.

Recommends are hard too

See if you have a X Recommends: A (= 1) and a new version of A, A (= 2), the solver currently will silently break the Recommends in some cases.

But let’s explore what the behavior of a X Recommends: A (= 1) in combination with an available upgrade of A (= 2) should be. We could say the rule should be:

• An upgrade should keep back A instead of breaking the Recommends
• A dist-upgrade should either keep back A or remove X (if it is obsolete)

This essentially leaves us the same choices as for the previous problem, but with an interesting twist. We can change the ordering (and we already did), but we could also introduce a new rule, “promotions”:

A Recommends in an installed package, or an upgrade to that installed package, where the Recommends existed in the installed version, that is currently satisfied, must continue to be satisfied, that is, it effectively is promoted to a Depends.

This neatly solves the problem for us. We will never break Recommends that are satisfied.

Likewise, we already have a Recommends demotion rule:

A Recommends in an installed package, or an upgrade to that installed package, where the Recommends existed in the installed version, that is currently unsatisfied, will not be further evaluated (it is treated like a Suggests is in the default configuration).

Whether we should be allowed to break Suggests with our decisions or not (the old autoremover did not, for instance) is a different decision. Should we promote currently satisified Suggests to Depends as well? Should we follow currently satisified Suggests so the solver sees them and doesn’t autoremove them, but treat them as optional?

tightening of versioned dependencies

Another case of versioned dependencies with alternatives that has complex behavior is something like

X Depends: A (>= 2) | B X Recommends: A (>= 2) | B

In both cases, installing X should upgrade an A < 2 in favour of installing B. But a naive SAT solver might not. If your request to keep A installed is encoded as A (= 1) | A (= 2), then it first picks A (= 1). When it sees the Depends/Recommends it will switch to B.

We can solve this again as in the previous example by ordering the “keep A installed” requests after any dependencies. Notably, we will enqueue the common dependencies of all A versions first before selecting a version of A, so something may select a version for us.

version narrowing instead of version choosing

A different approach to dealing with the issue of version selection is to not select a version until the very last moment. So instead of selecting a version to satisfy A (>= 2) we instead translate

Depends: A (>= 2)

into two rules:

1. The package selection rule:

   Depends: A

   This ensures that any version of A is installed (i.e. it adds a version choice clause, A (= 1) | A (= 2) in an example with two versions for A.

2. The version narrowing rule:

   Conflicts: A (<< 2)

   This outright would reject a choice of A (= 1).

So now we have 3 kinds of clauses:

1. package selection
2. version narrowing
3. version selection

If we process them in that order, we should surely be able to find the solution that best matches the semantics of our Debian dependency model, i.e. selecting earlier choices in a dependency before later choices in the face of version restrictions.

This still leaves one issue: What if our maintainer did not use Depends: A (>= 2) | B but e.g. Depends: A (= 3) | B | A (= 2). He’d expect us to fall back to B if A (= 3) is not installable, and not to B. But we’d like to enqueue A and reject all choices other than 3 and 2. I think it’s fair to say: “Don’t do that, then” here.

Implementing strict pinning correctly

APT knows a single candidate version per package, this makes the solver relatively deterministic: It will only ever pick the candidate, or an installed version. This also happens to significantly reduce the search space which is good - less backtracking. An uptodate system will only ever have one version per package that can be installed, so we never actually have to choose versions.

But of course, APT allows you to specify a non-candidate version of a package to install, for example:

apt install foo/oracular-proposed

The way this works is that the core component of the previous solver, which is the pkgDepCache maintains what essentially amounts to an overlay of the policy that you could see with apt-cache policy.

The solver currently however validates allowed version choices against the policy directly, and hence finds these versions are not allowed and craps out. This is an interesting problem because the solver should not be dependent on the pkgDepCache as the pkgDepCache initialization (Building dependency tree...) accounts for about half of the runtime of APT (until the Y/n prompt) and I’d really like to get rid of it.

But currently the frontend does go via the pkgDepCache. It marks the packages in there, building up what you could call a transaction, and then we translate it to the new solver, and once it is done, it translates the result back into the pkgDepCache.

The current implementation of “allowed version” is implemented by reducing the search space, i.e. every dependency, we outright ignore any non-allowed versions. So if you have a version 3 of A that is ignored a Depends: A would be translated into A (= 2) | A (= 1).

However this has two disadvantages. (1) It means if we show you why A could not be installed, you don’t even see A (= 3) in the list of choices and (2) you would need to keep the pkgDepCache around for the temporary overrides.

So instead of actually enforcing the allowed version rule by filtering, a more reasonable model is that we apply the allowed version rule by just marking every other version as not allowed when discovering the package in the from depcache translation layer. This doesn’t really increase the search space either but it solves both our problem of making overrides work and giving you a reasonable error message that lists all versions of A.

pulling up common dependencies to minimize backtracking cost

One of the common issues we have is that when we have a dependency group

`A | B | C | D`

we try them in order, and if one fails, we undo everything it did, and move on to the next one. However, this isn’t perhaps the best choice of operation.

I explained before that one thing we do is queue the common dependencies of a package (i.e. dependencies shared in all versions) when marking a package for install, but we don’t do this here: We have already lowered the representation of the dependency group into a list of versions, so we’d need to extract the package back out of it.

This can of course be done, but there may be a more interesting solution to the problem, in that we simply enqueue all the common dependencies. That is, we add n backtracking levels for n possible solutions:

1. We enqueue the common dependencies of all possible solutions deps(A)&deps(B)&deps(C)&deps(D)
2. We decide (adding a decision level) not to install D right now and enqueue deps(A)&deps(B)&deps(C)
3. We decide (adding a decision level) not to install C right now and enqueue deps(A)&deps(B)
4. We decide (adding a decision level) not to install B right now and enqueue A

Now if we need to backtrack from our choice of A we hopefully still have a lot of common dependencies queued that we do not need to redo. While we have more backtracking levels, each backtracking level would be significantly cheaper, especially if you have cheap backtracking (which admittedly we do not have, yet anyway).

The caveat though is: It may be pretty expensive to find the common dependencies. We need to iterate over all dependency groups of A and see if they are in B, C, and D, so we have a complexity of roughly

#A * (#B+#C+#D)

Each dependency group we need to check i.e. is X|Y in B meanwhile has linear cost: We need to compare the memory content of two pointer arrays containing the list of possible versions that solve the dependency group. This means that X|Y and Y|X are different dependencies of course, but that is to be expected – they are. But any dependency of the same order will have the same memory layout.

So really the cost is roughly N^4. This isn’t nice.

You can apply various heuristics here on how to improve that, or you can even apply binary logic:

1. Enqueue common dependencies of A|B|C|D
2. Move into the left half, enqueue of A|B
3. Again divide and conquer and select A.

This has a significant advantage in long lists of choices, and also in the common case, where the first solution should be the right one.

Or again, if you enqueue the package and a version restriction instead, you already get the common dependencies enqueued for the chosen package at least.

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The first Drupal Iberia 2024 at PACT in Évora, Portugal, marked a pivotal moment for the Drupal communities of Spain and Portugal.

Parabola's default makepkg.conf has long loaded /etc/makepkg.d/*.conf. As of makepkg 6.1.0, the program itself now loads /etc/makepkg.conf.d/*.conf, so this part of our makepkg.conf has been removed. Users who have /etc/makepkg.d/*.conf files need to move them to /etc/makepkg.conf.d/.

Debusine is a Free Software project developed by Freexian to manage scheduling and distribution of Debian-related tasks to a network of worker machines. It was started some time back, but its development pace has recently increased significantly thanks to funding from the Sovereign Tech Fund. You can read more about it in its documentation.

For more background, Enrico Zini and Carles Pina i Estany gave a talk on Debusine in November 2023 at the mini-DebConf in Cambridge.

We described the work from our first funded milestone in a post to debian-devel-announce in March.

We’ve recently finished work on our second funded milestone, culminating in releasing version 0.3.0 to unstable. Our focus on this milestone was on new building blocks to allow us to automatically orchestrate QA tasks in bulk. Full details are in our release history document. As usual, debusine.debian.net is up to date with our latest work.

Collections

In the previous milestone, debusine could store artifacts and run tasks against those artifacts. However, on its own this required the user to do a lot of manual work, because the only way to refer to an artifact was by its ID.

We now have the concept of a collection, which can store references to other artifacts (or indeed to other collections) with some attached metadata. These are structured by category, so for example a debian:suite collection contains references to source and binary package artifacts with their names, versions, and architectures as metadata. This allows us to look up artifacts using a simple query language instead of just by ID.

At the moment, the main visible effect of this is that our Getting started with debusine tutorial no longer needs users of debusine.debian.net to create their own build environments before being able to submit other work requests: they can refer to existing environments using something like debian/match:codename=trixie:variant=sbuild instead.

We also have a basic user interface allowing you to browse existing collections, accessible via the relevant workspace (such as the default System workspace).

Workflows

We’ve always known that individual tasks were just a starting point: real-world requirements often involve chaining many tasks together, as many Debian developers already do using the Salsa CI pipeline. debusine intends to approach a similar problem from a different angle, defining common workflows that can be applied at the scale of a whole distribution without being tightly coupled to where each package’s code is hosted.

In time we intend to define a way for users to specify their own workflows, but rather than getting too bogged down in this we started by building a couple of predefined workflows into debusine. The update_environments workflow is used to create multiple build environments in bulk, while the sbuild workflow builds a source package for all the architectures that it supports and for which debusine has workers. (debusine.debian.net currently has amd64 and arm64 workers, supporting the amd64, arm64, armel, armhf, and i386 architectures between them.)

Upcoming work will build on this by adding more workflows that chain tasks together in various ways, such as workflows that build a package and run QA tasks on the results, or a workflow that builds a package and uploads the result to an upload queue.

Next steps

Our next planned milestone involves expanding debusine’s capability as a build daemon. For that, we already know that there are a number of specific extra workflow steps we need to add, and we’ve reached out to some members of Debian’s buildd team to ask for feedback on what they consider necessary. We hope to be able to replace some of Freexian’s own build infrastructure with debusine in the near future.

The diffoscope maintainers are pleased to announce the release of diffoscope version 268. This version includes the following changes:

[ Chris Lamb ] * Drop apktool from Build-Depends; we can still test our APK code via autopkgtests. (Closes: #1071410) * Fix tests for 7zip version 24.05. * Add a versioned dependency for at least version 5.4.5 for the xz tests; they fail under (at least xz 5.2.8). (Closes: reproducible-builds/diffoscope#374) [ Vagrant Cascadian ] * Relax Chris' versioned xz test dependency (5.4.5) to also allow version 5.4.1.

You find out more by visiting the project homepage.

Here are the major changes available in the Plasma 6.1 beta:

• Triple buffering in KWin for smoother rendering and animations
• Support for the Wayland Explicit Sync protocol, which should improve life for NVIDIA users in particular
• Support for the Input Capture portal
• Remote Desktop system integration to allow RDP clients to connect to Plasma desktops, plus a new page in System Settings for configuring this
• New UX for Plasma's edit mode to make its modality more obvious and visually fancier
• Added a configurable edge barrier between screens, to make it easier to hit UI elements touching the edges between screens. This also allows auto-hide panels on edges between screens to work properly
• Fake session restore on Wayland that at least re-opens apps that were open last time, even if they don't get positioned in the same place. Support for real session restore is still being worked on
• Support for syncing the color of your keyboard's RGB backlight with Plasma's accent color
• Support for using the color profile embedded into the display, for displays that bundle these
• Support in Discover for replacing end-of-support Flatpak apps with their replacements
• Support for the battery conservation mode features on many Lenovo IdeaPad and Legion laptops
• Support for passwordless screen locking, for using it as a screensaver in an environment without security concerns
• You can now middle-click the Power & Battery widget to block and unblock automatic sleep and screen locking, and scroll over it to switch the active power profile
• Slightly rounder corners, and more consistency between corner radius everywhere
• Better window layout algorithm for Overview
• The "Shake cursor to find it" effect has been enabled by default
• New off-by-default effect to hide the mouse pointer after a period of inactivity
• System Settings Keyboard page has been rewritten in QML

View full changelog

Plasma Wayland Protocls 1.13.0 is now available for packaging.

This adds features needed for the Plasma 6.1 beta.

URL: https://download.kde.org/stable/plasma-wayland-protocols/
SHA256: dd477e352f5ff6e6ac686286c4b22b19bf5a4921b85ee5a7da02bb7aa115d57e
Signed by: E0A3EB202F8E57528E13E72FD7574483BB57B18D Jonathan Esk-Riddell jr@jriddell.org

Full changelog:

• plasma-window-management: add a stacking order object
• output device, output management: add brightness setting
• outputdevice,outputconfiguration: add a way to use the EDID-provided color profile
• Enforce passing tests
• output device, management: change the descriptions for sdr gamut wideness

Note: This blog was first published on September 29, 2021, and has been updated to reflect new information and insights. Takeaway: We explore why you should migrate your higher education website from Drupal 7 to Drupal 10. From enhanced security and performance to powerful new features and integrations, Drupal 10 offers a platform that is purpose-built for the needs of modern universities.