[cairo] How to test the gl backend?

Russell Shaw rjshaw at netspace.net.au
Fri Jun 4 06:28:50 PDT 2010

Bill Spitzak wrote:
> On 06/04/2010 05:53 AM, Russell Shaw wrote:
>> If gtk only uses top-level X windows, that means gtk has to register
>> for always-on mouse-motion events. Urgh...
> I think you are seriously in error about guessing what is inefficient!
> Believe me, creating and managing a hundred X windows requires ORDERS OF 
> MAGNITUDE more communication to the server than an event every time the 
> mouse moves 1 pixel. Besides it probably turned on mouse tracking for 
> those individual windows anyway!

In a properly done widget tool kit, no events are emitted from the X server
unless the mouse or keyboard button is pressed, or if the mouse crosses the
border of a window (only if the widget registered for those events).
Continuous mouse-motion events are usually only used in drag operations
when a mouse button is held down.

Continuous mouse-motion emission of events from the X server will make
networked applications utterly unuseable on all but the fastest (ie local)

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