Hi !
The screen dpi reported on my SP7 is wrong:
$ xdpyinfo | grep -B 2 resolution
screen #0:
dimensions: 2736x1824 pixels (723x482 millimeters)
resolution: 96x96 dots per inch
according to this microsoft tech specs page, it should be 267dpi. That's close to 3x more.
This leads to ridiculously tiny text rendering in every X11 application, since they are lead to think the screen is a lot bigger that it actually is. For now I've been fixing it by scaling the whole display up in my Desktop Environment's settings (KDE), but every graphic design app or css that tries to approximate what an centimeter is supposed to look like on screen is still massively wrong.
I'd like to track down where this mis-reporting comes from, but I'm not familiar with the graphic stack on linux at all. Who is providing X11 this information ? The kernel ?
I can give you the log of my X server starting:
...
[ 126.043] (II) modeset(0): EDID for output eDP-1
[ 126.043] (II) modeset(0): Manufacturer: LGD Model: 555 Serial#: 268435617
[ 126.043] (II) modeset(0): Year: 2019 Week: 0
[ 126.043] (II) modeset(0): EDID Version: 1.4
[ 126.043] (II) modeset(0): Digital Display Input
[ 126.043] (II) modeset(0): 8 bits per channel
[ 126.043] (II) modeset(0): Digital interface is DisplayPort
[ 126.043] (II) modeset(0): Max Image Size [cm]: horiz.: 26 vert.: 17
[ 126.043] (II) modeset(0): Gamma: 2.20
[ 126.043] (II) modeset(0): No DPMS capabilities specified
[ 126.043] (II) modeset(0): Supported color encodings: RGB 4:4:4
[ 126.043] (II) modeset(0): First detailed timing is preferred mode
[ 126.043] (II) modeset(0): Preferred mode is native pixel format and refresh rate
[ 126.043] (II) modeset(0): Display is continuous-frequency
[ 126.043] (II) modeset(0): redX: 0.640 redY: 0.330 greenX: 0.300 greenY: 0.600
[ 126.043] (II) modeset(0): blueX: 0.150 blueY: 0.060 whiteX: 0.313 whiteY: 0.329
[ 126.043] (II) modeset(0): Manufacturer's mask: 0
[ 126.043] (II) modeset(0): Supported detailed timing:
[ 126.043] (II) modeset(0): clock: 325.8 MHz Image Size: 260 x 173 mm
[ 126.043] (II) modeset(0): h_active: 2736 h_sync: 2784 h_sync_end 2816 h_blank_end 2896 h_border: 0
[ 126.043] (II) modeset(0): v_active: 1824 v_sync: 1827 v_sync_end 1837 v_blanking: 1876 v_border: 0
[ 126.043] (II) modeset(0): Ranges: V min: 48 V max: 60 Hz, H min: 0 H max: 0 kHz, PixClock max 328750 kHz
[ 126.043] (II) modeset(0): Maximum pixel width: 160
[ 126.043] (II) modeset(0): Supported aspect ratios: 5:4
[ 126.043] (II) modeset(0): Supported blankings: reduced
[ 126.043] (II) modeset(0): Supported scalings: vstretch
[ 126.043] (II) modeset(0): Preferred refresh rate: 20
[ 126.043] (II) modeset(0): LGD_MP0.1_
[ 126.043] (II) modeset(0): LP123WQ212604
[ 126.043] (II) modeset(0): EDID (in hex):
[ 126.043] (II) modeset(0): 00ffffffffffff0030e45505a1000010
[ 126.043] (II) modeset(0): 001d0104a51a117803ee95a3544c9926
[ 126.043] (II) modeset(0): 0f505400000001010101010101010101
[ 126.043] (II) modeset(0): 0101010101013f7fb0a0a02034703020
[ 126.043] (II) modeset(0): 3a0004ad10000019000000fd00303c00
[ 126.043] (II) modeset(0): 0021040a141414141414000000fe004c
[ 126.043] (II) modeset(0): 47445f4d50302e315f0a2020000000fe
[ 126.043] (II) modeset(0): 004c503132335751323132363034003c
[ 126.043] (II) modeset(0): Printing probed modes for output eDP-1
[ 126.043] (II) modeset(0): Modeline "2736x1824"x60.0 325.75 2736 2784 2816 2896 1824 1827 1837 1876 -hsync -vsync (112.5 kHz eP)
[ 126.043] (II) modeset(0): EDID for output DP-1
[ 126.043] (II) modeset(0): EDID for output DP-2
[ 126.043] (II) modeset(0): Output eDP-1 connected
[ 126.044] (II) modeset(0): Output DP-1 disconnected
[ 126.044] (II) modeset(0): Output DP-2 disconnected
[ 126.044] (II) modeset(0): Using exact sizes for initial modes
[ 126.044] (II) modeset(0): Output eDP-1 using initial mode 2736x1824 +0+0
[ 126.044] (==) modeset(0): Using gamma correction (1.0, 1.0, 1.0)
[ 126.044] (==) modeset(0): DPI set to (96, 96)
[ 126.044] (II) Loading sub module "fb"
[ 126.044] (II) LoadModule: "fb"
...
This seems to be fixable with a bit of X11 config, and if that's the case maybe we should document it in the wiki. But if someone could find the root cause instead and see what we can do about it that would be awesome.
Running debian package Linux surface 5.6.4-surface #1 SMP Tue Apr 14 08:07:37 UTC 2020 x86_64 GNU/Linux on debian 10.
Hi !
The screen dpi reported on my SP7 is wrong:
according to this microsoft tech specs page, it should be 267dpi. That's close to 3x more.
This leads to ridiculously tiny text rendering in every X11 application, since they are lead to think the screen is a lot bigger that it actually is. For now I've been fixing it by scaling the whole display up in my Desktop Environment's settings (KDE), but every graphic design app or css that tries to approximate what an centimeter is supposed to look like on screen is still massively wrong.
I'd like to track down where this mis-reporting comes from, but I'm not familiar with the graphic stack on linux at all. Who is providing X11 this information ? The kernel ?
I can give you the log of my X server starting:
This seems to be fixable with a bit of X11 config, and if that's the case maybe we should document it in the wiki. But if someone could find the root cause instead and see what we can do about it that would be awesome.
Running debian package Linux surface 5.6.4-surface #1 SMP Tue Apr 14 08:07:37 UTC 2020 x86_64 GNU/Linux on debian 10.