XGetImage returns junk with Xorg/dummy_drv/VTs

[Peter Harris]

Alan Cox wrote:
> Speed of switching for one. Nothing like copying several megabytes of
> data from a PCI/AGP card via PIO to make life suck.

Indeed.

> Presumably GetImage should either block or cause a redraw into an
> offscreen pixmap ?

GetImage can't block while waiting for a redraw, since the app
requesting the GetImage is often the same app that needs to do the
redraw (and will itself be blocked waiting for a GetImage reply).

But that's okay, since GetImage was effectively deprecated on day one:
"This request is not general-purpose in the same sense as other
graphics-related requests. It is intended specifically for rudimentary
hardcopy support."

GetImage contents are undefined if the window is obscured (which it
certainly is if the framebuffer is gone). Presumably, GetImage should
simply return a black rectangle in that case.

Peter Harris
-- 
     Hummingbird Connectivity - A Division of Open Text
Peter Harris                    http://connectivity.hummingbird.com
Research and Development        Phone: +1 905 762 6001
peter.harris at hummingbird.com    Toll Free: 1 877 359 4866