User: I want hi-res apps!

Dev: Sure, here you go.

User: But why is it so small on my new shiny tablet high density screen?

Dev: (SHit it worked okay for me) Okay now it detects the density and scale..

User: But when I move the window to my old good lcd screen it becomes way too big!

Dev: Okay let's see if I can dynamically adapt to a new monitor density, it's just one scale factor.

User: But when I put it on my big tv flat screen it is too small!!

Dev: (Oh shit you gotta be kidding me, the pixels are actually a viewing distance relative unit??!)

MacOS actually in my experience seems to handle this all perfectly. Normal-DPI screens you chose resolution and dragging windows between monitors works as you naturally expect (it pops between DPIs).

Concerning DPI and trackpad integration, Ubuntu should strive to be as Mac-like as possible, at least imo. Macs absolutely win in the trackpad arena; multitouch works like a dream, configurable gestures aplenty to achieve whatever you want (of course, it could always be more customizable).

DPI scaling between monitors work exactly as you'd expect. Windows stay the same size when moving between high-DPI and regular monitors.

These two problems are two of the biggest reasons I don't use Ubuntu (or any Linux) desktop (I use a macbook with a headless Ubuntu Server box and, when necessary, X11 forwarding over ssh).

Does it understand "I want 2x magnification on my 15" 4k laptop display, but not on my 43" 4k monitor"? Windows 10 decidedly does not, so I have to switch manually every time I switch display (just forget using both together), and it then tells me to close all my work and log out and in again to make scaling consistent between UI elements on screen.

Yes it does. It even remembers different window sizes and locations for different monitor configs :)

Huh? On Win10Ent I've got both of my displays set to different scaling factors and changes take effect immediately (like, as soon as I release the slider).

It works for me, with one annoying caveat. I have a set of regular 1920x1080 monitors on my desk at 100% scaling. My laptop has a 4k screen, and when I plug it in, I have it set to turn off that screen.

I have to log out when I plug/unplug or the windows will end up blurry or the wrong size.

Have you ever tried shouting at Microsoft about this?

I know they have a bad track record of not listening, but I think things might be different now, they seem to be a bit more receptive to feedback, particularly with the beta updates.

Or maybe I'm remembering the prerelease "hai where r the bugz halp" back when Win10 was not yet RTM...

This is exactly what I mean.

Yes it does, sometimes. But you can configure it as well. I think they used predefined lists of hardware though. EG if name contains tv then scale is 1

Pretty much. Works just fine when I hook my 15" laptop up to my 130" projector.

It's a bit weird to drag things onto my 4k TV through HDMI and try to track my microscopic mouse pointer to the tiny window to maximize my video, but otherwise works well. I suspect I could fix that in settings somehow though.

On newer macos shaking the mouse back and forth makes the pointer get larger (so you can find it).

https://discussions.apple.com/thread/7583592?start=0&tstart=...

KDE has a similar feature: When you hold Ctrl+Win, it will draw revolving circle segments in black and white around the cursor to allow you to find it. It looks like this: https://imgur.com/a/67wfI (You'll have to imagine the cursor inside these circles. My screenshot utility won't include it in the image for some reason.)

Heh...I think Windows 3.11 already had that feature (Ctrl -> Circle zooming in to mouse) :)

have you considered swapping out to a BIIIG mouse pointer? that's what I do on my home 65" HTPC/ TVPC :)

Yup.

I've always thought that arcdegrees should be what we measure UI's in: how much of a user's field of view does this thing consume? After all, what makes text "small" is that how much of my FoV it consumes (or doesn't). Not inches, or points, or pixels.

(Admittedly, "points" are still likely a good measurement for print. Perhaps one can work backwards and fudge point as a measure of angle if you consider 12 point font at a typical viewing distance.)

I assume the real hard piece is figuring out the distance the display is going to be viewed at. Some definite defaults exist (phones are typically about the same distance away, same with desktop monitors) but unique situations certainly can exist. (I'm also assuming that the monitor can report it's physical size and resolution; combined w/ viewing distance, it should be possible to calculate FoV.) If you did this, you should be able to mostly seemlessly split a window between two displays, and have it be equal "size" in the FoV. (of course, some displays have borders, so that fudges it a bit.)

> I've always thought that arcdegrees should be what we measure UI's in: how much of a user's field of view does this thing consume? After all, what makes text "small" is that how much of my FoV it consumes (or doesn't). Not inches, or points, or pixels.

That is a good starting point for calculating the default "optimal UI scaling", but there are going to be adjustments needed for the FoV of the whole screen area (not per pixel) too.

With large screens, for example 24-30" on your desk, just the per-pixel FoV measure will probably be good enough. You have plenty of "space" for windows and content, and want to get the optimal scaling.

But once you get to very small screens like phones, there is a tradeoff between keeping font and UI sizes comfortable, and being able to actually fit enough content on the screen without endless scrolling. I am willing to strain my eyes with smaller font sizes on my phone than on my laptop, just so that I can see more than 5 sentences of text at the same time.

"CSS Pixels" are actually supposed to be based on viewing angles:

    http://inamidst.com/stuff/notes/csspx

If the OS (not an app) could allow you to tweak the native pixel resolution, scale, size of each display, even under "advanced settings" that would go a long way towards helping.

This is at the Operating System level, not like some random one-off application.

For me, the one feature I miss the most is a checkbox option for "Native Scrolling"; Did this really need to be removed?

X11 did — run xdpyinfo and you'll see its idea of screen dimensions and resolution. (It's unlikely they'll have been configured correctly, of course.) If you look hard enough, you can find some ‘outdated’ plain-X software from the workstation era that respects it. It was the ‘Linux desktop’ crowd that threw that away, since they couldn't think beyond building Windows clones for PC clones.

And the vector-based competition to X (e.g. NeWS, Display Postscript) would have done better.

Simple answer is don't auto-detect. Allow the user to set the scaling factor per screen and then just auto-apply that when using that screen. This just requires a way to uniquely identify screens and requires the user to set the scaling factor for that screen once when first used.

Initial autodetection and scale-factor setting is ok. Otherwise most regular users would just say "all my icons and text are too small on my new notebook". Windows detects the high dpi in that case and sets the scalefactor to 200%, which gives a good starting point. Of course the user should be able to override this permanently if it isn't his preference.

s/his/their

As someone who loves singular they, I have a request: please don't do this. It is OK if grand parent uses he/him. Thanks!

The distance between of the third and fourth formulations of the problem is very small. Once apps can be dynamically redrawn with a scale factor, simply make the scale factor customizable.

Simply introduce zoom in/zoom out for the whole desktop separated to each screen like in browser (you can zoom certain tabs/sites and have that memorised). Problem solved.

> 1. HEADLINE: A way to have different scaling for external monitors hooked up to my HiDPI laptop.

This would be awesome. Even when both the laptop and the external screen are 1080p, different scaling could be helpful if you want to use a dual monitor setup effectively.

Unfortunately, it's a tough nut to crack given current desktop behavior. For example, you can have a window that straddles both monitors. What should the scaling be? You need to switch at some point as you're moving a window back and forth - when? So it's a challenge, but solving it would be so worth it!

Widows 10 handles different scaling (zoom) between monitors far better than any Linux distro I have used. A window keeps the zoom of where it came from until it is entirely on the new monitor. Works pretty well.

While I get that it's uncool to like Windows on HN, I really like Windows 10. With WSL, all of the CLI tools I need for development are here along with better hardware support (including suspend / resume, high DPI monitor support, latest GPU drivers / etc).

Plugging two 4K monitors into my laptop (which has a native 1080p display) is an awful experience when booted into Ubuntu. You either have to set the DPI to make the laptop display unusable or set it to make the 4K monitors look like $hit.

Plus... you know... games.

Windows isn't the best at multi-DPI in general though either. Only recently did Firefox on Windows get multi-DPI support - not sure if Chrome does yet because I gave up on it and went to dual 4K because the scaling was easier. If you want to see really good multi-DPI support, OSX is really good at it with most apps supporting it out of the box.

Multi-DPI is kind of a hack in general though and is likely to cause issues unless applications have been tested for it very thoroughly, it causes serious issues on major frameworks like Electron and Qt - though both of their support for it is improving slowly. If you want things to work smoothly for now, try to stick to 1 DPI setting.

I think you're confusing Windows DPI scaling availability vs lack of support from the apps you use.

It's not windows fault the apps don't take advantage of DPI. You can also disable dpi scaling for individual apps.

You're right, but even many builtin Microsoft apps - while they supported DPI scaling - did not support multi-DPI switching and rather than scaling properly just scaled pixels and looked blurry.

It's "not Windows fault", sure but it certainly makes it a worse experience than other platforms like OSX where multi-DPI is much more commonly supported.

I would much prefer the Windows behavior to what I see on Linux. Right now, if I open an app that doesn't support high DPI, it is just unusable because it is so tiny.

Couldn't you just manually reduce your screen resolution? Or is that too drastic to be worth it?

It's worth considering whether there is some flaw with windows multi dpi scaling such that apps don't use it. Firefox and Chrome have scaled properly on Mac for years now, while even Windows 10 ships with first party apps that don't scale right. (E.g. device manager.)

For sure that this has been an issue in the past with Windows. UWP helps make muli-DPI work by default in new applications.

Sure, but 99% of my Windows software isn't UWP. It's all good and well to say it's there, but that doesn't make the experience good for the user. Contrast to KDE and OS X where it just works for 99% of software.

I mean, I get it, same issue as Vista for Microsoft - people expect 100% backwards compatibility, but it turns out that terrible design decisions made many years ago tend to mean you need to break compatibility. Just like UAC, resolution scaling will be an issue that becomes less painful in Windows over time. Right now it's not great, however.

I mean, you say that, but on KDE, for example, every application except one on my system works with DPI scaling (the odd one out is Unity3D) - that's because at the QT level DPI scaling is built-in, so the toolkit supports it and the applications get it for free. Clearly this wasn't the case for the older Windows UI stuff, where they are literally just scaling the image of the window up (which means horrible looking text).

Actually, the really old windows stuff did support scaling - the 'Large fonts (120%)' option was there almost forever. I remember that original Delphi, circa 1995, supported it.

Just most apps chose to ignore it, the developers took the 'anyone uses 96 dpi anyway' attitude and at the end of 90's most applications started to suck at 120 dpi.

Yep, Windows API already had support for logical pixels in the 16 bit days and all good books always preached to convert between logical pixels and physical ones.

I guess people got lazy, as you say.

I think that the monitors stayed more or less the same later pixel density for a very long time. Is only been gradually increasing very slowly for 20 years, until a few years ago.

No point in spending time on logical pixels if it makes almost no relevant difference...

It's

Anything running its own renderer doesn't get to benefit from component scaling since they don't use components.

That was my point - running KDE, this is extremely uncommon, running Windows, it's practically every application.

The problem isn't just scaling between two different resolutions, it's the inconsistencies (yes, apps don't take advantage but that's not the only issue). For example, if I want 200% 4k (my monitor) and 100% 1080p (my 2 side monitors), I have to choose between ultra-tiny text on my 4k with regular text or blurry text on my 1080ps.

http://i.imgur.com/o1S8ZUt.png

Is that Windows 10? On my Windows 10 Ent desktop I'm able to set the scale factor of each display independently.

http://imgur.com/a/5378F

This is Windows 10. How do I enable that option?

Erm...click on the display you want to change (1,2,3) and simply drag the slider?

This month's Windows update fixes DPI scaling for old toolkits.

Yes, it's true that there are issues. It seems like most Microsoft apps handle multi-DPI well. By comparison, on Fedora 25 (the latest release), the only program I have found that handles multi-DPI is Terminal. Firefox doesn't do it.

Yeah, Windows support is better than Linux for it, but it's still pretty iffy. While IE and a few other things do, even stuff like Windows Explorer and OneNote doesn't handle multi-DPI well or even just runtime DPI changes in general, I'll RDP my box from a 100 DPI system and have my session screwed up when I come back to my system.

If you're making a decision about whether to make a purchase, don't make it unless you're prepared to do it all at once. Stick to ~100 DPI until you can make a commitment to go all at once.

Chrome hast had DPI scaling since 2015 on Windows. I remember having to report lots of initial bugs. Now it works fine.

DPI scaling yes, but not multi-DPI, when dragging from a 100 DPI monitor to a 300 DPI one text should remain sharp and not blurred by scaling pixels. Or even vice versa.

>While I get that it's uncool to like Windows on HN

That has not been my experience here at all. There is a rather active, and sometimes vocal, Windows fan base around here. Misconceptions about the current state of desktop Linux are commonly seen as it seems most people around here only use either Mac or Windows.

Agreed, while I see some MS/Windows hate... some of it technical, some political, and a mix of founded/fud... There's been a fair amount of counter to that.

I mostly use mac at work, mostly windows at home, and a bit of linux for servers, and my htpc (most of my casual browsing at home)... Each experience is fairly different. And they all have pluses and minuses. That said, more often than not, I prefer the Windows UI desktop/menu, but osx & unity app integration and linux/bash shell environment. I wish that Ubuntu/unity would integrate more of the menu/taskbar features found in windows. (And bring back natural scrolling checkbox)

Microsoft integrated Ubuntu instead.

My experience (currently running two 27" panels at 3840x2160 and one 27" panel at 2560x1440 in KDE for most stuff, Windows for gaming, and previously had one of the first edition retina MBPs with external non-retina displays):

OS X, years ago when the first retina MBP was released, did everything right. It was seamless from monitor to monitor, scaling done well.

Windows 10, now: OK, ish. Most applications scale badly with blurry text because it's just literally scaling the image afterwards. Newer applications are fine. The actual scaling isn't great - having a window half on one monitor and half on the other leads it to 'picking one' and looking weird on the other.

KDE, now: Pretty good. Correct scaling once you set it up. The autodetection can be dodgy, and the DPI scaling for text isn't linked to the rendering scaling for windows, for some reason. The GUI still only gives you a single scaling option for all monitors, but the autodetection can do different for each monitor, and environment variables can be set to solve it manually. The actual scaling is perfect for the vast majority of things. Things scale correctly and no blurriness. The only application that doesn't handle scaling is Unity3D, so everything is tiny (no fallback to raw image scaling).

In general, it's what you'd expect for interace stuff across the platforms - Linux does it right, but the interfaces around it are bad, Windows does it fine for new stuff, old stuff (which is most stuff) sucks, but the interfaces are OK for doing it, and OS X gets it all right.

Edit: Just to be clear, it's only the Unity3D editor that doesn't do scaling, the actual games work fine, as you'd expect they just get the full space and the game chooses how to render to it. To be fair to Unity about the editor, they support scaling on OS X, and the Linux build is still a beta. It is annoying though.

I use this on Windows 10: http://windows10_dpi_blurry_fix.xpexplorer.com/ and it works fine. If you have blurry text, disable DPI scaling in that app (right-click -> Properties -> Compatibility -> Disable DPI scaling) and this will take over and make it usable. There are a couple of applications that act wrong no matter what (Battle.net for example), but most of the time this fixes it well enough.

I only use Windows 10 for gaming, so fortunately I don't really need to worry. Useful for those who use Windows all the time, though.

Windows also gets my vote when it comes to the per-app volume mixer controls which have been awesome since Windows Vista.

https://blogs.msdn.microsoft.com/larryosterman/2005/12/15/vo...

PulseAudio provides this feature and actually provides more features and functionality than Windows. Ubuntu's default mixer isn't the greatest so I recommend this instead:

    sudo apt install pavucontrol

You can then find it in the application menu labeled, "PulseAudio Volume Control". It lets you set the volume for individual applications (and with Chrome, individual tabs!) and also pick which output/input device will be used.

It lets you configure some neat tricks. For example, you can setup an audio device that forwards to another computer running PulseAudio, an RTP receiver, and a few other similar protocols then set say, Spotify to output to that device. So if you have some network-enabled audio receiver somewhere in your house/office/whatever you can send audio from your Linux workstation to it.

You can of course also pass that audio through various filters/plugins to mess with the sound before it goes out to the remote receiver. For example, equalize it, noise removal, etc. PulseAudio supports LADSPA plugins so if you wanted to you could setup a little Raspberry Pi audio receiver at your front door and yell at solicitors in a robotic voice from your desktop. All with a bit of PulseAudio configuration fiddling =)

I still remember the first time I was in a computer lab and I leaned too far away from my computer and my headphones that were blaring music popped out... and the whole room WASN'T subjected to the same loud music. And I opened up the Kubuntu audio controls and plugged in my headphones and the volume slider suddenly jumped up, then I unplugged again and it muted again. "Woah."

I remember trying it on whatever Windows computers were in the lab just to make sure I wasn't crazy and that this wasn't there all along, and sure enough, they kept the same volume no matter whether the headphones were plugged in or not.

One of the first PulseAudio victories I remember, at a time when I vaguely recall that it was a newcomer and people were really pissed at PulseAudio's bugs and recommending just straight ALSA instead.

+1, PA + pavucontrol are very flexible. You don't even need weird protocols to send your audio to another computer, I just used its tunnel module (enable it in the receiver, then configure its IP on the sender) to send my browser's audio output to my home server, which has a decent stereo attached. The latency is quite good too, the delay even over wifi is barely noticeable.

There's also pulseaudio-dlna[0]. It works as advertised.

[0] https://github.com/masmu/pulseaudio-dlna

Thanks for the heads-up! This is one thing I miss mightily on my Mac.

This feature comes by default with PulseAudio, maybe Ubuntu doesn't expose it well enough in their audio settings. I think Gnome Settings has it, KDE definitely does.

Pulse Audio solves the same thing for Linux.

I get correct auto scaling-switching like this on Gnome 3 with Wayland, but only for a subset of programs (basically those that are fairly vanilla GTK+3), and at the cost of weird bugs with Wayland and program support thereof that still crop up fairly regularly.

I've always resorted to xrander and can get the screen looking pretty good. Though I really think something like this should just work.

Weston does multi-DPI really well. When you drag a window between monitors, the half on the HiDPI monitor is scaled and the half on the LoDPI monitor is unscaled. So it looks perfect without windows growing or shrinking when you move them to another monitor like GNOME on wayland.

I'd love to read more about how this was done, if you have a link perhaps.

macOS handles that edge case. It just displays the window in only one screen. The one with the biggest area of the window shown. There is no need to be held back by cases like this.

If you zoom in, you can sort of force parts of one monitor to be shown on the other monitor. You can see how everything's upscaled/downscaled from there.

> This would be awesome. Even when both the laptop and the external screen are 1080p, different scaling could be helpful if you want to use a dual monitor setup effectively.

Actually, this is especially true when both are 1080p, because laptop screens are never as big as desktop monitors, and we also tend to use them closer. I have this exact problem right now but I think I've just adjusted my eyes over time to squinting at 1080p at 14", or perhaps I turned on some display scaling and forgot about it.

> For example, you can have a window that straddles both monitors. What should the scaling be?

Intuitively, I feel like you should use the physical DPI of both screens to make sure that the window has the same physical dimensions on both. But that'd probably lead to weird scaling factors like 1.17 instead of nice round ones, and thus fuzzy scaling, so it probably couldn't quite work. I guess perhaps you'd just snap each display's DPI to the closest predefined value (eg. .25 increments which I think most systems use these days). Then you'd get a similar-sized part on both sides of the boundary.

But yeah, I think overall if you actually use physical DPI for scaling everything should work out close to nicely.

FWIW, macOS changes a window's DPI mode when the cursor that is moving the window passes over from to one screen to another. Just tried that out. :D

That's what happens when "Displays have separate spaces" turned on. (With that setting on, windows are only present on one monitor at a time, and, when dragging a window, that transition happens when the mouse cursor moves between displays.)

With "Displays have separate spaces" turned off (so windows can be present on more than one monitor at a time), it looks like windows take their DPI setting from whichever monitor the majority of the window is on-- with my current two-monitor setup, the DPI transition happens at the halfway point of a window, regardless of where the mouse is as I'm dragging.

Leaving aside the implementation difficulty, the answer to "what should the scaling be" seems obvious? Use the monitor scaling for the part shown on that monitor. The switch should happen on a monitor level, not on a window level.

The painting happens on window level, that's why it handled there. Application paints the window whenever it receives event "paint me" for it and it cannot paint different portions of a window at different DPI - from the applications POV, it is a single canvas. Another thing is, that the window resize and dpi change are separate events, so you cannot really call it twice in a row with different DPI and expect the app not getting confused.

Another approach would be to let the application render at higher DPI and the compositor would downsample the portion on the lower DPI display.

OSX handles this by upsampling/downsampling the parts of windows that are drawn on the other screen.

This isn't just external monitors! MBP with "retina" screens are also unusable for Ubuntu :(

Fedora with Gnome shell on Wayland already handles both 1 and 2, although power managements is about the same as Ubuntu and Wayland comes with its own set of issues.

I switched from Ubuntu to Fedora about a year ago and am quite happy with it.

Well 1 depends on Wayland actually detecting your external monitor, I normally end up having to drop back to X to get it to detect my secondary 28" 4K monitor :-(

I couldn't figure out where I can change the different scaling for the external monitor on my fedora 25. My 1080p external monitor just looked huge comparing to my dell xps 13 hidpi display.

It requires Wayland features that are used by GNOME 3.24 (so F26).

really, there's a native multitouch support for touchpads? do you have more info about that?

Yes there is native 4 finger swipes to change desktop on Wayland. And I wrote an extension to add 3 finger gesture support for an action of your choice. Check it out here: https://github.com/mpiannucci/GnomeExtendedGestures

I can't find much information, but things like scrolling, switching work spaces etc. worked out of the box for me when I was testing Fedora 25 a month or so ago.

Two-finger scrolling works really well on Fedora with Wayland, in fact at some point it appears to have become default behavior (at least on my machine running the latest version).

Fedora uses libinput. Of course, it is not without issues from those, who would like to tweak every little setting. Libinput is designed to be as automatic and configuration-less as possible.

+1. I recently got an Dell XPS 13 and hooked it up to my external monitor (4K). Icons were way too small so I adjusted those and standard text size. But getting applications (e.g. PyCharm) to run at a reasonable size was frustrating (I had to google it and then modify some configuration file somewhere). With OS X, which I just came from, the external monitor "just worked" when I plugged it into my Macbook Pro.

it really is a mess. i connected a 4k xps 15 to FHD monitor, the only way for it to work is via open source nvidia drivers and using xrandr to scale the external monitor and then use other settings to scale everything to FHD. that and some other things made me return the xps and order the new macbook.

Windows scaling should auto configure and work in any modern application. It always works like that for me, and I only have issues for software written in 2003 in Java or really old versions of QT.

> (I had to google it and then modify some configuration file somewhere)

I even had to do this with Chrome [1]. It's crazy how obscure this was when I was setting things up. Other apps, like Gimp, still look like shit because I can't find a way to do the same thing; their GUI just rends at a tiny scale and is difficult to use.

[1] https://superuser.com/a/1120078/103402

One way to solve the scaling issue is to set the external monitor to a virtual higher resolution while still driving it at its native resolution (with scaling down done in GPU).

Actually Linux/Xorg generally support this out of the box, it is just the higher-level software that would need to make use of it. You can try it youself:

xrandr --output <output-name> --scale 2x2

the result should be the given monitor will appear to have twice the resolution, so if applications believe they are running on a high-DPI display, they will look fine on the external monitor as well.

However due to lack of support and awareness in desktops doing just this might leave you with an unsatisfactory configuration, e.g. part of the desktop erroneously shown on both monitors - you might need to use further xrandr commands to setup the regions that each monitor displays.

I use the same approach to solve this issue on a Windows 7 system I am using, it is just slightly more involved (I need to setup a custom resolution in the Nvidia control panel).

Unfortunately, this scales after drawing. The entire point of hiDPI is to have a crisper image. To achieve that, the scaling must be done at the drawing level.

Unity and Gtk would scale everthing up, so things that are properly drawn before being re-scaled.

So quality will be there.

For normal/low-DPI screens instead, you'd scale everything down, so you'd lose some memory CPU power, but you'd still get the quality result.

Battling xrandr is not for the feint of heart. It is tedious to get the right behavior and differs from one display to the next (the precise dimrnsions, etc..)

HiDPI is still a huge problem in the linux desktop I can't count the number of hours I've spent researching and fiddling with it. Wayland is the answer, but it's slow moving, and Sway currently looks terrible when scaling double.

The biggest issue with Wayland is video drivers. Try getting Wayland to work with any proprietary blob, and see your efforts fail miserably.

#1 is absolutely the biggest one for me and #3 is a solid second.

I have a Macbook Pro with retina and stopped using linux simply because I couldn't get a good resolution on my laptop and monitors. And then when traveling (flights etc), ubuntu chewed through battery probably 3 to 4x as fast as OSX so I wasn't good for that either. As a result, I have been on OSX for a couple years now but would love to be back on ubuntu some day.

I have the dual problem of 1.HEADLINE: I've got a HiDPI notebook and suffer when I have to connect it to a common 1080p screen.

Better out of the box HiDPI support would be great.

Autdetection would Be nice, but just being able to set the scaling option in one place and having it apply not only to my desktop but the login manager as well would be very useful.

Also, afaik there is no documentation on changing the scaling factor in the login manager, or at least not in the official docs.

I would not buy a standard resolution monitor at this point, so having simple support for it in Linux is very important to me.

Ubuntu Unity Developer Here...

I'm mostly replying at the point 1., as it's closed to what I do...

I know we should offer an UI for that, but waiting for that you can just workaround this.

Well, as said unity supports scaling, although it's not possible to scale toolkits per monitor.

However... There's actually a good workaround for this, that works fine for multiple monitors.

The idea is that you scale everything up to 2x / or your maximum scaling (including window contents), then you scale the non-HiDPI monitors down using xrandr --scale

For example, if you want to use normal resolution there, you just have to do something like:

xrandr --output <OUTPUT> --scale 2x2

In this way it will be scaled down, and everything will be readable and almost 1x1.

You can test this in normal resolution monitor as well, and you'll see things should be pretty good.

I should find some time to implement this directly inside UCC / USD, so that users will get this for free...

Notice that there's also a bug in X causing some mouse trapping, so you'd probably also need X to be patched as explained in this bug: https://pad.lv/1580123 (we'd like to include this upstream, but we're waiting for X upstream approval for that)

On 1.: Seriously, I was gonna write the exact same thing. Just today I researched once again, since it's quite a hassle, and nowadays seems pretty common to have a HiDPI laptop screen in combination with a standard-DPI external screen.

I had the same problem yesterday, I use fedora but we share the same pain missing this feature. It would be awesome to have this setting. Being able to set different scaling for external monitors is a must have feature.

Thanks for mentioning TLP - I hadn't heard of it before

3. agree with the default WM; no issues (same or better than Win) battery life with i3wm. In my experience ofcourse.

More work on gesture!

Including the ability to configure what gestures you want in a GUI interface!

if multi-monitor support was as solid as it is on macOS, i'd likely switch

Would love support for #2

I would absolutely be in favor of #1 and #3.