Hi There,

I'm still quite new to PD and graphical programming, and there's something I'm really having trouble sorting out, which I'd find really easy to code in something like perl or python etc.

I want to write a patch/abstraction(?) that has the following inputs:

1. Lower Bound (Float)
2. Upper Bound (Float)
3. Rate (Float)
4. Start/Stop (Bang?)

And just one output.

The patch is a counter that 'bounces' in increments/decrements determined by the rate inlet between the lower and upper bounds.

Does anyone have something that I could study to help me get the feel for this? I know what I want, my brain just wont let me do it PD...

I've attached a little bit of perl that is what I'd like to emulate in PD.

http://www.pdpatchrepo.info/hurleur/bouncer.pl

As a sensible translation there is a behaviour you might feel is an error. The count bounces between upper_bound + step and lower_bound - step, because the increment/decrement is done before the comparison, which is simpler to express in Pd.

To fix it you can rearrange the components given. They are separated in the parent to better explain the relation to Perl statements.

The first is an accumulator/integrator x[n] = x[n-1] + y which grows or shrinks by y on each step

The second is a comparator used in each branch of the conditional "if" part to update the incrementor step size.

http://www.pdpatchrepo.info/hurleur/bouncecount.pd

Thanks!

That's really very helpful. I'm not too worried about the boundary oversteps, it doesn't need to be so precise for what I have in mind.

Thanks again,

Jamie