New display server

[Jiri Svoboda]

Work on new display server as a replacement for compositor is in progress at ​https://github.com/jxsvoboda/helenos/commits/gfx

This is the first step of overhauling the graphics/UI stack. Here's some of the high-level goals.

• An abstract rendering API and window update protocol that can be used both for App ↔ Display server and Display Server ↔ Display Driver communication and other things
• Make it possible to conserve memory (compared to all windows being always fully memory-backed)
• Make the memory retention and communication mode a decision of the display server, not an inherent property of the display protocol / API
• Display protocol should explicitly denote frame boundaries and frame timing
• Support a wider range of pixel formats (<32 bpp, >32bpp) including text mode
• Better support for multi-seat and multi-point

The scope of this ticket is achieving rough parity with current compositor-based solution.

[Jiri Svoboda]

I created this enhancement request to stop hijacking #652.

[Jiri Svoboda]

For progress updates, see here:

• ​http://jiri-svoboda.blogspot.com/2019/11/working-on-new-helenos-display-server.html
• ​http://jiri-svoboda.blogspot.com/2020/01/the-window-system-saga-continues.html

[Jiri Svoboda]

Merged in this ​commit

[Jakub Jermář]

Milestone renamed