Mouse polling

Björnke von Gierke bvg at mac.com
Sun Mar 3 17:47:01 EST 2002


On Sonntag, März 3, 2002, at 07:25 , Scott Raney wrote:

(snipedisnip)

>> I just don't understand how this can lead to any problem at all? A
>> different mater is the following example:
>>
>> script:
>> repeat while the mouse is down
>> set the loc of field "grabMe" to the mouseLoc
>> end repeat
>
> This is really the core of the problem: this loop uses 100% of the CPU
> time, regardless of the speed of the processor, bringing the system to
> its knees, causing poor feedback for your app, and making your system
> unresponsive to any other processes running on it.  You see, on a fast
> system, 99.99% of the time through that loop you're setting the loc to
> exactly the same coordinate!

Ok I got it kinda, thanks to the 99.99 % ... but why exactly does it 
bring the multiuser enviroment to its knees? I mean, the following 
doesn't do any harm (as far as I know):

set the myOwnProperty of Stack "StackWithCustomProperties" to 0.001
repeat until the myOwnProperty of Stack "StackWithCustomProperties" > 
0.234
   add 0.001 to the myOwnProperty  of Stack "StackWithCustomProperties"
end repeat

so why is "the mouse" a system hog, but any other property isn't?

still confused
Björnke von Gierke




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