DPI

Introduction

We try to synchronize the DPI from the client to the server, so that applications will render with the correct settings and "look right" on the client.

Caveats:

• DPI support is much improved in version 0.16. With previous versions, your mileage may vary
• with X11, there are far too many places where the DPI can be looked up, many places where it can be overriden - it is hard to get right
• for virtualized "hardware DPI" which some applications calculate from the virtual monitor dimensions, you will need a patched wiki/Xdummy driver and wiki/FakeXinerama
• many applications will not reload the DPI settings, so they must be started after the client connects to get the correct DPI value

Links

• ​Of DPIs, desktops, and toolkits
• win32 API:
  • ​WM_DPICHANGED
  • ​GetDpiForMonitor
  • ​SetProcessDpiAwareness
  • ​Writing DPI-Aware Desktop and Win32 Applications
• ​Scaling Windows - The DPI Arms Race, in particular: ​Windows 8.1 - More DPI Changes
• ​About High Resolution for OS X
• ​Qt: Retina display support for Mac OS, iOS and X11
• ​xserver forces 96 DPI on randr-1.2-capable drivers, overriding correct autodetection
• ​please add option to avoid forcing of 96dpi

Related xpra tickets

• #697 gtk screen dimension detection is broken with high dpi displays on windows7 and later
• #163 pass client DPI preference to server (and use sane defaults of 96dpi)
• #976 client display scaling
• #919 frame extents synchronization

Data

TODO!