Linux – How to zoom into the desktop but maintain high resolution for fonts etc

arch linuxawesomewaylandx11

I recently bought a 4K screen (or UHD i.e. 2160p to be exact) and use it on my tower running Arch Linux. As a window manager I use awesome which runs on top of compton for tear-free compositing, as described in this post.

The screen is quite large but still has a higher pixel density than previous screens I used. I would thus like to scale the whole desktop (zoom into it) to have a more comfortable experience (and no longer need to lean towards the screen to read tiny text).

While scaling I still want to take advantage of the high resolution of my screen (e.g. smoother font rendering), thus I do not want to use something like xrandr, which renders the desktop for a smaller resolution and then scales up the rendered raster image.

I tried to find out on which level of my GUI setup (awesome => compton => X) I would need to apply such a configuration, but I have not yet found any useful information. I was also wondering whether this can be achieved under X at all. Apparently, the Wayland compositor Weston supports some kind of zooming in and out the desktop. If it is required, switching to Wayland would certainly be an option too.

In fact I feel that I lake some basic understanding about how the GUI rendering pipeline generally works (starting from the window manager). I would greatly appreciate if someone could point me at some insightful readings.

Best Answer

Hi fellow Awesome WM user! I have had this same issue and found out that Awesome WM currently does not support dpi scaling. So that means we are on our own. A lot of applications pick up the dpi from X server. So make sure your X server has the right dpi (several ways: Xorg conf monitor size, .Xresources, cal xrandr with dpi flag...).

Best solution I found until now: just use a large font-size.
You can also increase the sizes of the menu's and other elements that you find too small.

Wayland is not an option if you want to keep using Awesome WM because it implements the X server api, wayland is something different.

IIRC compton is also not going to help because it doesn't help you with scaling acording to dpi.

Related Solutions

X, Xorg and D-Bus: what is the difference

You are asking five questions here, and might be better asking five questions ☺ But I'll jump in:

X is a server and can be compared to a "web server" in that it is a process that listens for incoming connections that speak a particular protocol (the X protocol) and it issues answers. The connections come from X clients, which may be on the local host or on a remote host accessed over a network.
X11 is a "major version" of the X protocol, which has evolved since inception. X11 is the most recent protocol and the most common. (Xorg is an implementation of an X server, X libraries and a collection of clients, all talking X11. There are other implementations: the largely defunct XFree86; commercial ones such as Hummingbird Exceed; forks such as XQuartz, which runs on Mac OS X)
A "window manager" is an X client which manages windows. It typically has the responsibility to decorate windows with bevels/borders, drop shadows, a menu bar containing buttons, etc. -- and handle the logic of window placement; support windows being dragged, resized or re-arranged, etc.
X requires input and it has a shared responsibility to manage that with the Kernel. Historically, X did a lot of hardware management itself. In modern times, on the Linux platform, X is gradually becoming "smaller" and delegating this responsibility to the Linux kernel. The advantages of this are: smaller X codebase; fewer "crossed-wires" with the kernel and X both trying to manage the same stuff. (an example of this is the Linux event interface, where events from mice etc. are interpreted and translated by the kernel and its drivers into the standard interface at /dev/input/event*, which is consumed by the X server). Note that on other platforms (BSD, Solaris) X is still quite monolithic.
There are many, many ways for processes to communicate with each other. I believe X clients can interact by way of the X protocol (for example, traditional X window managers need to know when other clients draw windows, in order to decorate them; pagers need to know when a window's size or position changes, in order to reflect that in the pager). D-Bus is a modern inter-process communication (IPC) technology developed to address the shortcomings of other methods. It is not X specific.

Calibrating a touch-screen on dual monitors (one touch one not)

I have it working now. The first thing I did was to install the latest version of the display driver from the xorg repo. I'm not sure if this step was absolutely necessary since it doesn't seem to have changed the output from xrandr much, but it didn't hurt anyway:

$ sudo apt-add-repository ppa:xorg-edgers/ppa
$ sudo apt-get update
$ sudo apt-get dist-upgrade
$ aptitude search <my-graphics-card-brand>
$ sudo apt-get install <corresponding package>

Now xrandr shows DP-1 with more properties:

$ xrandr
Screen 0: minimum 320 x 200, current 2732 x 768, maximum 8192 x 8192
eDP-1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
   1366x768      60.00*+  40.00  
   1360x768      59.80    59.96  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   960x600       60.00  
   960x540       59.99  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   800x512       60.17  
   700x525       59.98  
   640x512       60.02  
   720x450       59.89  
   640x480       60.00    59.94  
   680x384       59.80    59.96  
   576x432       60.06  
   512x384       60.00  
   400x300       60.32    56.34  
   320x240       60.05  
VGA-1 disconnected (normal left inverted right x axis y axis)
DP-1 connected 1366x768+1366+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1360x768      59.80    59.96  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   960x600       60.00  
   960x540       59.99  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   800x512       60.17  
   700x525       59.98  
   640x512       60.02  
   720x450       59.89  
   640x480       60.00    59.94  
   680x384       59.80    59.96  
   576x432       60.06  
   512x384       60.00  
   400x300       60.32    56.34  
   320x240       60.05  
HDMI-1 disconnected (normal left inverted right x axis y axis)

And then start X and run the following command to assign eDP-1 as the touchscreen:

$ xinput --map-to-output $(xinput list --id-only "Elan Touchscreen") eDP-1

The manpage of xinput (v.1.6.2) mentions that the device name can be given as a string as well. Therefore, this would also work:

$ xinput --map-to-output "Elan Touchscreen" eDP-1

Best Answer

Related Solutions

X, Xorg and D-Bus: what is the difference

Calibrating a touch-screen on dual monitors (one touch one not)

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