[PD] [hid] users poll

Mathieu Bouchard matju at artengine.ca
Fri Jun 17 01:18:00 CEST 2005

On Wed, 15 Jun 2005, Hans-Christoph Steiner wrote:
> On Jun 15, 2005, at 1:23 PM, Mathieu Bouchard wrote:
>> I think that as long as integers still can be used, there is no problem 
>> with supporting symbols. I mean I've seen cases where the enforcing of 
>> symbols means having to use [sprintf] all over the place in a 
>> less-than-elegant way.
> Integers/floats are not supported in [hid] because that would defeat one of 
> the main purposes that inspired me to write it: to have a clean, 
> straightforward API.

Woops, I had thought only about messages sent to HID (e.g. steppermotors 
controlled by HID, or forcefeedback joystick). See below for input 

> For example, you probably won't need to use a lookup table to understand 
> [route abs_x abs_y abs_throttle] but most people would need it for 
> [route 1 3 14].

however if I have a row of 7 distance sensors, such as what is being used 
by 13 artists at Vidéographe this month, [gate 7] or [shunt 7] is more 
straightforward than [route in1 in2 in3 in4 in5 in6 in7]. (The sensor box 
most likely wouldn't have any meaningful labels at all for those axes; is 
it possible that they wouldn't have labels at all? what happens in this 

> [sprintf] with [hid] data, but please try out strange, unorthodox 
> configurations

Using the same example above, if I want to build an array using values 
from the seven sensors, so that the shape of an object (as "seen" by the 
sensors) can be visualized, is there no better means than using a big 
route and a bunch of messageboxes ? If the sensor id is an integer, then I 
can just use one single object: [tabwrite myarray]. (or [s myarray])

If I have really a lot of sensors, I could instead use [for 0 64 1] -> 
[sprintf in%d] -> [listfind], or I could use [atof] (that I posted a few 
days ago).

>> Actually comparing symbols is much faster than comparing floats, if you run 
>> Pd on a 386 or on a PDA.
> That good to know. I was thinking strcmp() versus ==.

Sorry, actually a float == can be optimised back to the same as int ==. It 
depends on whether the compiler knows about it (or else you are running a 
FPU emulator and it's certainly much slower)

> So comparing symbols in Pd is basically a == operation using the pointer 
> integers, right?


> If you ever feel like checking out my [hid] code, matju, I'd love advice on 
> optimization.  Since it can run up to once every 1ms, optimization is key.

depends on how many 386's with USB you use =)

how common is USB on PDA's ?

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