[cairo] How to test the gl backend?

Russell Shaw rjshaw at netspace.net.au
Sat Jun 5 21:53:45 PDT 2010

Clemens Eisserer wrote:
>> With one top-level X window for the whole tree of widgets, every time you
>> scroll that area even by 1 pixel, you're forced to redraw a 400x600 pixel
>> area. Is doable on a local system, but hopeless on a slower network.
> Wouldn't it possible to do the scrolling with a  cheap (in terms of
> traffix) XCopyArea call, and only re-draw the "uncovered" area?

Hi Clemens.E,
Thankyou, yes that would work. Yes i forgot about XCopyArea() as a way
to do it. I hadn't put more effort into the one-top-window approach
because i had the sub-window approach working ok. I'll have to resurrect
some code that synthesizes window-crossing events from continuous mouse
events. Using one top X window means various passive-grab problems when
tabbing between multiple "entry" widgets can be avoided. The system would
be more portable with the one-topwindow approach. If other toolkits are
doing that, then i'll have another go.

Atleast to be cairo related, widgets could be drawn with cairo as
an option.

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