I have a mix of both 4k (3840x2160) and 1080p monitors and I need to scale so the text on the 4k is more readable.
I’m having an issue because --scale does not zoom, it only changes the view port size. The issue only occurs with the amdgpu, not the intel gpu.
When I set
xrandr --output DVI-D-1-0 --mode 1920x1080 --pos 7680x0 --scale 2
the output is not scaled, the monitor shows the top left quadrant of 3840x2160. The rest of the workspace spills over to the next monitor and below the monitor.
DVI-D-1-0 connected primary 3840x2160+7680+0 (normal left inverted right x axis y axis) 509mm x 286mm
1920x1080 60.00*+
1680x1050 60.00
1280x1024 75.02 60.02
1440x900 60.00
1280x800 60.00
1152x864 75.00
1280x720 60.00
1024x768 75.03 60.00
800x600 75.00 60.32
640x480 75.00 59.94
720x400 70.08
But if I scale on a monitor attached from the onboard intel gpu, it scales to fit 3840x2160 into 1920x1080
xrandr --output HDMI1 --mode 1920x1080 --pos 11520x0 --scale 2
HDMI1 connected 3840x2160+9600+0 (normal left inverted right x axis y axis) 510mm x 290mm
1920x1080 60.00*+
1280x1024 75.02 60.02
1280x960 60.00
1280x800 59.91
1152x864 75.00
1280x720 60.00
1024x768 75.03 70.07 60.00
832x624 74.55
800x600 72.19 75.00 60.32 56.25
640x480 75.00 72.81 66.67 59.94
720x400 70.08
I also tried panning, but not I get errors.
xrandr --output DVI-D-1-0 --mode 1920x1080 --scale 2 --pos 7680x0 --rotate normal --panning 1920x1080
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 29 (RRSetPanning)
Serial number of failed request: 68
Current serial number in output stream: 68
Any idea what causes the discrete gpu to behave differently?
5.4.80-2-MANJARO
xorg 1.20.9
i3-gaps 4.19-1
rx570
amdgpu 20.2.3