Took the whole yesterday and a bit of today, but I've got window closing animations working! These turned out to be tricky because they need storing a snapshot of the surface render tree to draw once the app is gone.
Some apps may start destroying their subsurfaces before the main surface, like alacritty with its sctk CSD, making it very easy to miss parts of the window in the snapshot, and therefore in the closing animation.
Also, windows closing to the left no longer shift the view!
Definitely one of the most complex animations yet: window resizing.
Just the crossfade effect itself took a while to get working with all the window geometries and buffer offsets, and then there's the whole multiple window orchestration with Wayland's asynchronous nature. (I don't do animation transactions yet, that'll be a whole other level of complexity on top.)
Happy with the result though, and it's cool that it seamlessly works with block-out-from screencast.
Window movement across columns is now animated too!
These weren't complex per se, but very *finicky*. Spent quite a bit of time chasing down all the offsets and coordinates to add and subtract to avoid jumps, but it seems to all work well now!
All the animations, plus VRR, today in niri 0.1.5: https://github.com/YaLTeR/niri/releases/tag/v0.1.5
I also remade the demo video to showcase the animations and some of the newer features!
Another tricky feature, rounded corners! Took several days, but I believe I've got a pretty complete implementation.
You (manually) set the window corner radius and whether to force-clip the window. You can set radius per-corner to match GTK 3 apps. It works correctly with subsurfaces, blocked-out windows, transparency, gradient borders, resize and other animations.
Optimization-wise, opaque regions and even overlay plane unredirection work where possible!
Also, we've now got a little #niri setup showcase thread 
https://github.com/YaLTeR/niri/discussions/325
Added (stole from GNOME Shell as usual) a screen transition action, so now I can finally switch between dark and light in style
(of course, it works with blocked-out windows)
Okay, time for an actually useful feature: interactive mouse resizing (yes, finally). This was, as it goes, quite fiddly to implement, especially since niri has to negotiate with the window during the process.
I also added a double-resize-click (i.e. trigger a resize twice quickly) gesture to reset the window height or to toggle full width. Suggested by FreeFull on our Matrix and worked out very well! Really starting to feel quite nice with mouse.
(still no transactions yet)
nvim really taking its time processing all this 1000 Hz worth of resizing lol
Since I'm in a mouse gesture mood today: hooked up the horizontal touchpad swipe to Mod + middle mouse drag and omg it feels so good with the spring deceleration and all
(of course it also correctly avoids the touchpad scaling, so that when using the mouse gesture, the cursor location is always exactly anchored to the view position)
Now for something fun. I'm experimenting with the ability to set custom shaders for animations. Today I added custom shader support for window-close, which lets me make this cool falling down animation!
This is entirely optional of course, and there's no performance impact if you don't use it. Also, custom shaders, like the rest of the niri config, are live-reloaded, making it easy to play around with them.
Been fixing quite a bit of interactive resize jank and other small stuff since the last time, but also added custom shader support for window-open, thus completing it for all three main window animations (open, close, resize).
Now I didn't actually have any good idea of what I might want in a window open custom shader (I like the default), so I made a simple expanding circle animation to showcase it.
Niri 0.1.6 with interactive window resizing, rounded corners, named workspaces, mouse view scrolling, animation custom shaders, screen transition!
https://github.com/YaLTeR/niri/releases/tag/v0.1.6
Didn't realize quite how many release notes there would be this time; even had to use an extra level of headings. 
Over the past few weeks I've been working on fractional scaling for niri. A simple implementation took about a day, but to do it *properly* I had to refactor the entire layout code to work in floating-point.
The result is well worth it though. Borders, gaps and windows are always physical-pixel aligned, and not restricted to integer logical pixel positions. There's no blur or position-dependent +-1 px jank. Fractional-scale-aware clients remain crisp at any scale.
So it turns out that changing PipeWire screencast stream resolution on the fly is actually not that hard! Which is great news because it's required (or at least very desirable) for implementing window screencasting.
Phew, finished the initial implementation of window screencasting in niri! Complete with stream resolution change on window resizing.
Some details are still iffy regarding frame timing and frame callbacks, especially to obscured windows, but it *should* work decently fine for now.
Icons are missing in the portal dialog because apparently Shell keeps track of Wayland app ID to .desktop file mapping internally and returns the .desktop file name to the portal for it to get the icon. Which is a bit too much effort for me to replicate for now.
Fixed transparency support. Turns out the BGRA format should've been in a separate pod, rather than as a choice in the same pod. Should've looked at Mutter code sooner as usual..
niri v0.1.7 is out with fractional scaling, window screencasts and many smaller improvements!
Apparently there's a cool Pango flag that enables subpixel glyph positioning which makes things scale smoother and improves kerning! Thanks Benjamin (the GTK maintainer) for the suggestion
Oops, looks like niri had outstarred PaperWM on GitHub 
PaperWM introduced me to (and made me fall in love with) scrollable tiling. It's a solid implementation on top of GNOME, so you get all the benefits of running a stable and well-supported DE (and Xwayland). PaperWM is also a very direct inspiration for many parts of niri!
Implemented the thing where you can toggle the mouse pointer on the screenshot after the fact (by pressing P). Gonna add a help panel here soon to remind you of this.
One of the niri users has contributed a gradient interpolation color space setting! Now you can do pretty gradient borders in srgb-linear, oklab and oklch (in all four hue directions).
I made a COPR for git builds of niri: https://copr.fedorainfracloud.org/coprs/yalter/niri-git
Apparently this is a thing you can do; relatively easily, even. It's fully automatic, triggers on a webhook from GitHub.
Thanks Michael (my4ng) from our Matrix channel for showing me the relevant docs and doing the initial work!
also in an act of severe procrastination i decided to try drawing a diagram of the redraw state machine: https://github.com/YaLTeR/niri/wiki/Redraw-Loop
Spent a better part of today, but I've got dmabuf modifier negotiation fully working in my pipewire screencasting code in niri! This happens to finally fix screencasting on NVIDIA GPUs. Still haven't got any GStreamer pipeline working though, maybe needs a pipewire update.
Apparently, my AMD selects a BGRA format modifier that has two planes. Some out of band info I suppose. And on Intel a preferred BGRA modifier has three entire planes!
My Wayland compositor, niri, turns one today! 
Here's v0.1.8 with bind key repeat, screenshot UI pointer toggle, gradient color spaces, wlr screencopy v3 and output management, and lots of other improvements: https://github.com/YaLTeR/niri/releases/tag/v0.1.8
omg, my friend drew a birthday nirik 
i recorded a demo video for the focus-follows-mouse section to showcase it lol
Several days and a lot of hair pulling later, I *think* I got resize transactions working?? Maybe? Hopefully?
Resize transactions is when all windows that must resize together, resize together, with no mismatching frames in between. For example, all windows in a column must add up to the full screen height.
This requires correct configure acks on the client (looking at you, Blender) and very careful state update delaying and resize throttling on the compositor side.
narrator: there was still one case where it didn't work due to a bug
okay, surely this time it definitely works for all correctly written clients
Here's one mainly for people who disable animations: window closing now runs in a transaction with the other windows resizing. This means, no background flicker.
There's been another logo discussion in the niri Matrix room with some quite interesting concepts emerging. Here's one by Endg4me_ with edits by bluelinden and myself, and inspiration from a concept by ElKowar.
What do you think?
I'm working on an "event stream" IPC for niri where you get notified about events as they happen. For example, "workspace switched" or "keyboard layout changed".
To give it a good test, I actually started implementing native niri support in Waybar. You can give it a try too: https://github.com/YaLTeR/niri/pull/453#issuecomment-2317110904
I finished the initial event stream IPC implementation for niri. My Waybar fork implements a decent amount of the modules niri/workspaces, niri/window, niri/language. Please give that a try, also anyone who makes IPC scripts or bars please give a try to the event stream IPC itself so we can find any design flaws before merging.
The PR you will need: https://github.com/YaLTeR/niri/pull/453#issuecomment-2321730996
Waybar fork is linked from there.
The other day, Christian Meissl finished updating and publishing the libdisplay-info bindings [1]. This is quite exciting because, unlike edid-rs, it can parse the manufacturer/model/serial from pretty much any monitor.
So, today I spend a few hours integrating the manufacturer/model/serial monitor addressing all throughout niri: config, IPC, niri msg, screencast output selector. You should now be able to write/use "SomeCompany CoolMonitor 1234" everywhere!
Set up CI rustdoc publishing for niri-ipc: https://yalter.github.io/niri/niri_ipc/
This has the entirety of the niri IPC documented, including the new event stream events.
After the Waybar maintainer speedran merging my niri modules and releasing, I would feel bad delaying any longer, so here's niri 0.1.9 :)
Event stream IPC for bars, better window resizing, properly named outputs, on-demand VRR, out-of-the-box fix for NVIDIA flickering, and other improvements!
Over the past 2 weeks I've been slowly but surely working on the interactive move niri PR [1] by @pajn. It's already got me to fix quite a bit of tech debt in the layout code, which is cool.
The PR is still rough around the edges, but mostly works, and I switched to running the branch on my own systems to give it thorough testing.
(also no, this is not the Floating Layer yet, though it's a good step towards that)
Attaching a video of what it looks like rn
Made interactive move work on touch (and resize too while I was at it), didn't need that many changes actually
Added a bit of rubberbanding before the window is "dragged out" of the layout. Should help avoid unintended layout changes.
Along with a few more fixes I did, I think interactive move should be good to merge? It's not 100% perfect and jank free, but I'm fairly sure I got all the important things done. Will give it some more testing.
Suddenly, @drakulix showcasing the Cosmic session running on, among other compositors, niri! On the big screen at the Ubuntu Summit 
somehow this touch moving under stationary pointer works better than i expected
(yes trying to do a precise left click with an elbow was difficult)
By the way! I'll be giving a talk at RustCon in Moscow on December, 6! 
Wherein I will briefly describe what a Wayland compositor is, and then show several testing and profiling workflows that I've been using to keep niri stable, robust and performant.
(The invitation to submit a talk was completely unexpected, guess niri found its way into the right eyes. )
There will be a recording, though in Russian.
Interactive window moving, laptop lid and tablet mode switch binds, mouse and touchpad scroll speed setting in today's niri v0.1.10 release!
https://github.com/YaLTeR/niri/releases/tag/v0.1.10
Also, niri-ipc is now on crates.io, but keep in mind that it will not be Rust-semver-stable: https://crates.io/crates/niri-ipc
Added scaffolding for layer rules, along with a block-out-from rule. Now you can finally block notifications from screencasts!
Though, layer-shell surfaces don't have a "geometry" so if they have shadows or transparent padding, all of that becomes solid black, since niri has no way to know where the "actual content" of the layer surface is (that's what geometry is for windows).
Thanks to Christian Meissl's fix in Smithay, the git version of niri correctly shows nested pop-up menus in lxqt-panel. They also submitted a fix for invalid pop-up spawning to ironbar, which makes it work on Smithay compositors.
Somehow, a small change for tests escalated into trying to completely refactor how animation timing works in niri. And right now I find myself at the exact opposite of this picture. Unfortunately, time has not stopped and is causing problems
Like three complete refactors later, I think it's... working? For real this time? No weird issue is gonna sneak up that undermines the whole design?
Nothing seems to have caught on fire after one more day of personal testing and one more day in main. So here's a technical page I wrote about the the new niri animation timing design and its motivations: https://github.com/YaLTeR/niri/wiki/Animation-Timing
Today I merged a PR by FluxTape which adds "always empty workspace before first" to niri. At the surface this is just a simple config flag with obvious behavior, but it's actually full of edge cases! Things like which workspace to focus at startup. The code refers to workspaces by index in many places, and those all shift when you suddenly insert an empty workspace at index 0.
Took several days to catch them all even with our randomized tests, but I think it should be good now.
>did a +4,657 −4,237 refactor in the layout code
>while testing, already found two uncaught regressions introduced in previous niri releases, and no issues with the refactor
@YaLTeR the day of xwayland will be implemented will be the day im trying switching to niri
@ralen gonna be a while im afraid :p
@YaLTeR there is no WAY this released mere HOURS after rebasing to Plasma 
@YaLTeR makes me think of a keyboardsmash
dnjksflnabsdfbadhsafkvghdka
@YaLTeR "pick a window, any window"
@YaLTeR my dog shakes like that and he's fine.
@YaLTeR Biblically accurate WM 
@bemyak you haven't seen biblically accurate yet
@YaLTeR Show me! 
(Should we then port niri to TempleOS 
)
@YaLTeR indeed its shuffling them, is the output order random? :)
@lw64 nah, though would be fun
@tbernard wdym by mosaic behavior?
@YaLTeR The thing where windows aren't forced to go all the way to the edge of the screen. Basically, tiling but windows still get to have some say in what their default size should be.
https://blogs.gnome.org/tbernard/2023/07/26/rethinking-window-management
@tbernard I see. Niri doesn't do free-form 2D tiling; the niri layout is Workspaces which contain Columns which contain Windows. (i.e. you can't further split a window horizontally, and similarly can't put 1 long window below 2 columns)
Columns try to pad window heights to screen height. It wouldn't be too difficult to use less height and visually center, but generally full height is what you want (especially with 2+ windows in a column).
(cont.)
@tbernard Now for the sizes. Niri always asks windows a specific *height* (since columns try to pad to screen height), but you can set niri to let the window pick its initial *width*. However, in practice I personally found this useful only for a few select apps like video player; generally you want 50% or 33% of screen width by default.
When I get to floating, I intend to make it so windows that open floating pick their default size (like it works elsewhere).
@YaLTeR Hmm interesting, yeah the column-based nature makes it not the best fit I guess. Do you have any plans for a more flexible 2D mode? Would be cool to experiment with some of these ideas with real apps/windows, even in a limited setting, to make progress on the metadata side.
@tbernard Haven't had plans for more sophisticated tiling. My current plan is to implement normal floating windows (a few unresolved UX questions there on how best to combine it with the scrolling/tiling layout), and then use it and get a feel for what annoying windowing situations remain. Then think what could be done about them.
My idea for floating is slightly different from PaperWM: I imagine that you should just drag a window out into floating. We'll see how well that works in practice.
@tbernard @YaLTeR @pajn Is that proof of concept you showed a year back on your blog still a goal for the design team? Did it just stall?
This one: https://blogs.gnome.org/tbernard/2023/07/26/rethinking-window-management/
@ada_magicat @YaLTeR @pajn Definitely, but the design team doesn't have an army of developers to command :)
We're basically waiting for someone to try an implementation, so we can test the behavior with real apps and iterate on the details. Until then it's basically stalled, yeah.
@ada_magicat @tbernard @YaLTeR @pajn this is as far as the implementation of that idea has gotten (as far as I know): https://gitlab.gnome.org/heikkiket/window-mosaic-mode/
@YaLTeR I wish that's how Gnome worked, so cool
I hope the tiling concept from last year gets implemented at some point.
@YaLTeR Awesome! What device are you using there?
@fuzzyherbivore it's an EGOBAS portable touchscreen
@YaLTeR buttery smooth animation.
@YaLTeR That looks/feels very appealing. Really lovely work. 
@YaLTeR That looks great! So much attention to details that I think a lot of WMs don't care about
@YaLTeR
nice :)
@YaLTeR ohh nice, that pointer thing will probably fix kicad for me :)
@YaLTeR 32 left and it's a round number! :3
@YaLTeR What?! I can follow the niri dev here?! Sweet!
I adore niri!
@m welcome to my Big Thread since the Beginning of Times :)
@YaLTeR I scrolled back a bit... wow!! 
@YaLTeR uncaught regressions should be considered bugs in the regression discovering process