Re: X server latency

[Carsten Haitzler (The Rasterman) <raster rasterman com>]

On Tue, 17 Apr 2007 23:17:04 +0200 (CEST) Rachid KHAZAZ <rachiddelta yahoo fr>
babbled:

> Hi all,
> I have two questions :
> 1) I have written a program (see the attached file) that displays the x
> coordinates of the pointer when the MotionNotify event is catched. When
> moving the mouse very slowly, the coodinates shown like 150,149,148...... But
> when I move the mouse very quicly, the coordinates like 150, 125, 80.... How
> do you explain the difference between the two sets of results.

the mouse hardware literally is sending "bigger moves" so the mouse says "i
moved 25 units up" when you from from 150 to 125 - x ends up showing this (i'm
dropping the complexity of mouse acceleration etc. for now). so x is literally
showing what it gets as input.

> 2) I have written an X client which moves the pointer by XWrapPointer()
> function, when executing this program and the program of 1), the last one
> doesnot detect the pointer motion caused by the XWrapPointer(). Do you have

check for enter/leave events too.

> an idea about that? and how can i produce the detection of a "simulated"
> mouse motion. Thank you all.

you can't detect. motion events (or enter/leave) from XWarpPointer are seen as
the same as a real device being moved.


-- 
------------- Codito, ergo sum - "I code, therefore I am" --------------
The Rasterman (Carsten Haitzler)    raster rasterman com
裸好多
Tokyo, Japan (東京 日本)