[PD] cartopol~ outputs inverted phases (bug report)

[IOhannes zmölnig]

On 12/16/2011 01:05 AM, Alexandre Torres Porres wrote:
> oops, I guess I didnt understand you then.
> 
> well, I tried myself, and in max [cartopol~] matches [cartopol], That is;
> they both give same results in MAX.
> 
> Now in Pd, they don't match, [cartopol~] gives inverted phases, but
> [cartopol] in Pd matches the [atas2] and [expr] versions.
> 
> And the results in MAX also are in agreement to [atan2] and [expr] or
> [cartopol] in Pd.
> 
> So Pd's [cartopol~] is the odd one out.

i'm not sure i can follow. i think there is still some information missing.

in Max, [cartopol~] and [cartopol] match.
in Pd, [cartopol~] and [cartopol] are inverted. this really means:
cyclone's [cartopol~] is inverted with respect to the [cartopol] you are
using.

cyclone's [cartopol~] is to match Max's [cartopol~], phase wise. if it
doesn't, then it's a bug in cyclone.

so as a first step, you should check whether they output the same in Max
and Pd/cyclone, if you send them the same input.


i don't know, where your [cartopol] implementation comes from.
if it comes from cyclone, then it must match Max's [cartopol]
implementation. if it does not, it's a bug in cyclone. if Max's
[cartopol] and [cartopol~] behave differently (which they don't), then
cyclone's implementations must behave differently as well.

however, if the [cartopol] you are using is _not_ from cyclone, this
doesn't matter at all.
e.g. zexy's [cart2pol] doesn't care at all about Max and cyclone
compatibility; i don't know whether they behave the same and if they
don't then i'm sure i wouldn't change [cart2pol]s behaviour (as it is
designed to be mathematically "correct", not to be Max compatible)


fmgasdrt
IOhannes

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