[PD] hidio bug?

Hans-Christoph Steiner hans at eds.org
Wed Jul 25 19:45:15 CEST 2007

Ah yes, this is an annoyance with many USB HIDs that output relative  
data.  The data they output is in effect speed, but they don't output  
zero.  What those devices are actually outputting is the amount of  
change in pixels since the last measurement of location.  If there is  
no change, they output nothing.  So you don't get a zero.

Personally, I think this is a bad design, and makes them hard to work  
with if you are doing something other than moving a cursor around on  
a screen.  (I suppose it makes things a bit more efficient for moving  
a mouse cursor around on a screen).

I dealt with this problem by using a delay to output a 0 when the  
stream of data has stopped for a 10 ms or so.  Check the attached patch:


On Jul 24, 2007, at 8:17 PM, Diego Azar wrote:

> Absolute value. So if the last value was -3 and the mouse stop  
> moving, it stays there. What I meant was that if the number was  
> greater than absolute value of 1, and the mouse stops, it stays  
> there. I put abs(1) because the sign is logical. If I move from  
> right to left it stays in a negative number, what seems correct. If  
> it is in the oposite direccion it stays in a positive number, so  
> the sign thing seems to work fine. What number is it supposed to  
> give if there´s no movement?   one?
> When moving fast it always have this problem
> Could it be some delay between the on of the mouse´s led and the  
> "data transfer" from the os to pd?
> I tried it with two mouses ,one with a led-cam-dsp system and the  
> other with a ball-system, and they had the same behavior.
> Sorry if I wasn´t clear enough.
> Diego.
> Hans-Christoph Steiner <hans at eds.org> wrote:
> I read your question again, and I don't quite get it.  What's abs(1)?
> .hc
> On Jul 24, 2007, at 4:37 AM, Diego Azar wrote:
>> Hans, thanks for your reply. I'm working with hidio because it  
>> works better, with my configuration, than the hid.
>> thanks again, Diego.
>> Hans-Christoph Steiner <hans at eds.org> wrote:
>> First off, I must say [hidio] can be quite rough since it's very  
>> alpha.  But I am glad to have people testing it, with that in  
>> mind. But if you are using [hidio] and not [hid], and you are  
>> getting "rel_x" as a message, then that is a bug.  "rel_x" is the  
>> old [hid] style messages.  [hidio]'s messages look like [relative  
>> x 0 1(
>> .hc
>> On Jul 22, 2007, at 9:49 PM, Diego Azar wrote:
>>> Hi. I'm using the hidio object with a mouse and it seems there's  
>>> something I'm not getting. The problem is when routing the list  
>>> from the rel_x to obtain the x relative axes; the value,  
>>> sometimes, is greater than abs(1) when the mouse is not moving.  
>>> Is this behavior correct? Is this a bug? Has it anythig to do  
>>> with the numbers hidio gets from the /dev/event$ or something  
>>> within the OS?
>>> I'm using a Debian based distro.
>>> Thanks, Diego.
>>> Boardwalk for $500? In 2007? Ha!
>>> Play Monopoly Here and Now (it's updated for today's economy) at  
>>> Yahoo! Games.
>>> _______________________________________________
>>> PD-list at iem.at mailing list
>>> UNSUBSCRIBE and account-management -> http://lists.puredata.info/ 
>>> listinfo/pd-list
>> --------------------------------------------------------------------- 
>> -------
>> I have the audacity to believe that peoples everywhere can have  
>> three meals a day for their bodies, education and culture for  
>> their minds, and dignity, equality and freedom for their  
>> spirits.      - Martin Luther King, Jr.
>> Pinpoint customers who are looking for what you sell.
> ---------------------------------------------------------------------- 
> ------
> Mistrust authority - promote decentralization.  - the hacker ethic
> Pinpoint customers who are looking for what you sell.


"[W]e have invented the technology to eliminate scarcity, but we are  
deliberately throwing it away to benefit those who profit from  
scarcity."        -John Gilmore

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20070725/2d39ef44/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mouse.pd
Type: application/octet-stream
Size: 2294 bytes
Desc: not available
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20070725/2d39ef44/attachment.obj>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20070725/2d39ef44/attachment-0001.htm>

More information about the Pd-list mailing list