23 Nov
2022
23 Nov
'22
7:01 p.m.
Jim composed on 2022-11-23 11:41 (UTC-0400):
Anyway, xrandr can be asked to report the EDID
information for an
attached screen. And that can be parsed to get information such as
the (alleged) physical screen size (in mm). Knowing the number of
pixels on the screen, the DPI value can be calculated.
Here is a (zsh, but may work with other shells) to get
the information
of the (first only?) attached screen:
Instead of all that work measuring and calculating, use a tool that does the work
for you:
inxi -Gaz --vs
inxi 3.3.23-00 (2022-10-31)
Graphics:
Device-1: Intel HD Graphics 630 vendor: ASUSTeK driver: i915 v: kernel
arch: Gen-9.5 process: Intel 14nm built: 2016-20 ports:
active: DP-1,HDMI-A-2,HDMI-A-3 empty: DP-2,HDMI-A-1 bus-ID: 00:02.0
chip-ID: 8086:5912 class-ID: 0300
Display: x11 server: X.Org v: 1.20.14 driver: X: loaded: modesetting
alternate: fbdev,vesa dri: iris gpu: i915 display-ID: :0 screens: 1
Screen-1: 0 s-res: 3600x2640 s-dpi: 120 s-size: 762x558mm (30.00x21.97")
s-diag: 944mm (37.18")
Monitor-1: DP-1 pos: primary,bottom-l model: Acer K272HUL serial: <filter>
built: 2018 res: 2560x1440 hz: 60 dpi: 109 gamma: 1.2
size: 598x336mm (23.54x13.23") diag: 686mm (27") ratio: 16:9 modes:
max: 2560x1440 min: 720x400
Monitor-2: HDMI-A-2 mapped: HDMI-2 pos: top-right model: Dell P2213
serial: <filter> built: 2012 res: 1680x1050 hz: 60 dpi: 90 gamma: 1.2
size: 473x296mm (18.62x11.65") diag: 558mm (22") ratio: 16:10 modes:
max: 1680x1050 min: 720x400
Monitor-3: HDMI-A-3 mapped: HDMI-3 pos: top-left model: NEC EA243WM
serial: <filter> built: 2011 res: 1920x1200 hz: 60 dpi: 94 gamma: 1.2
size: 519x324mm (20.43x12.76") diag: 612mm (24.1") ratio: 16:10 modes:
max: 1920x1200 min: 640x480
API: OpenGL v: 4.6 Mesa 22.1.7 renderer: Mesa Intel HD Graphics 630 (KBL
GT2) direct render: Yes
Each monitor's actual dimensions and DPI are accurately reported (from EDID, if it
exists), and the entire screen's /logical/ dimensions and DPI (what the software
uses: s-dpi: 120) are also reported.
--
Evolution as taught in public schools is, like religion,
based on faith, not based on science.
Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!
Felix Miata