This year there was another “Display Next Hackfest”, this time thanks to AMD organizing and hosting the event at their office in Markham, Toronto. Just like the last hackfests, there were other compositor developers and driver developers present, but in addition we had the color experts Charles Poynton and Keith Lee to pester with questions, which was very useful. In general, the event was very productive.| Xaver’s blog
Many people are, understandably, confused about brightness levels in content creation and consumption - both for SDR and for HDR content. Even people that do content creation as their job sometimes get it really wrong.| Xaver’s blog
Most operating systems nowadays provide a feature like night light: Colors are adjusted over the course of the day to remove blue light in the evening, to potentially help you sleep1 and make your eyes more comfortable. Despite the common claims about it, scientific evidence for night light improving sleep is still lacking afaik ↩| Xaver’s blog
This one required a few other features to be implemented first, so let’s jump right in.| Xaver’s blog
In Plasma 6.2, KWin switched from doing linear blending with HDR to blending in a gamma 2.2 space. Let’s take a look at what that means, and why it was done.| Xaver’s blog
Fractional scaling is hard. Anyone that had the misfortune of working on it knows that… so it won’t surprise a lot of people that it’s not all figured out yet! Today I’ll talk about the fractional scaling problems with KWin’s server side decorations, and why we need to do an API break to fix it.| Xaver’s blog
Profiling displays is already not a super simple thing on its own, but things get more complicated when you try to profile your display in Wayland - profiling applications don’t support Wayland yet, some APIs on the compositor side to make it work well are still missing, and there’s a general lack of information on the topic. So today I’ll show you how to profile your display in the Plasma Wayland session.| Xaver’s blog
KWin had a very long standing bug report about bad performance of the Wayland session on older Intel integrated graphics. There have been many investigations into what’s causing this, with a lot of more specific performance issues being found and fixed, but none of them managed to fully fix the issue… until now.| Xaver’s blog
Since the last two posts about this topic (part one, part two) there has been some more progress, so let’s take a look.| Xaver’s blog
Recently news went around about explicit sync being merged into Wayland protocols, and in the wake of that I saw a lot of people having questions about it, and why it was such a big deal… So here’s a short-ish explanation of what it is, why it’s needed and what the benefits are over the old model.| Xaver’s blog
The solution and the problem: atomic modesetting When it comes to driving displays on Linux there’s some legacy APIs that we don’t care about, and the drm/kms API. This API isn’t exactly one API though, it has two variants, legacy modesetting and atomic modesetting.| Xaver’s blog
In this post I’ll talk a bit about HDR and color management, and where we are with implementing them in KWin. Before jumping into the topic though, I need to add a disclaimer: I will be simplifying a lot of things significantly, leaving others out entirely and as I am by far not a color expert, almost certainly write a few things that are wrong. If you want more credible sources and dive into the details of how all the color stuff works, I recommend you have a look at the color-and-hdr repo...| Xaver’s blog
In my last post about HDR and color management I explained roughly how color management works, what we’re doing to make it work on Wayland and how far along we were with that in Plasma. That’s more than half a year ago now, so let’s take a look at what changed since then!| Xaver’s blog