We have to sort this out! The denormals bug in freeverb~ _seems_ to have been fixed by following Julius' advice. I made a makefile with
-fno-trapping-math as a flag and so far so good. I haven't had a problem with the freeverb~ object pegging the CPU. May I advise that this is implemented in PD-extended, since it causes my patch to NOT WORK AT GIGS! I simply cannot take any more embarrassment. I want to play live, otherwise there's simply no point doing anything! The second one I have discovered is in bsaylor/svf~ and there's no makefile for this in the subversion repository. I notice in the source code there is a FLUSH_TO_ZERO definition. Interestingly, when I try to compile this external using a bog-standard makefile on Ubuntu 8.10, it causes an error: cc1: warnings being treated as errors svf~.c: In function ‘run_svf’: svf~.c:59: error: dereferencing type-punned pointer will break strict-aliasing rules svf~.c:60: error: dereferencing type-punned pointer will break strict-aliasing rules Now, I'm trying to unpick the statement: #define FLUSH_TO_ZERO(fv) (((*(unsigned int*)&(fv))&0x7f800000)==0)?0.0f:(fv) which is being called on lines 59 and 60 of bsaylor/svf~.c, causing the compiler to choke, and (perhaps) causing my drumsynths to break! And by the way, where is the source code for the _other_ svf~ external? Ed --- On Wed, 1/7/09, Julius Smith <[email protected]> wrote: > From: Julius Smith <[email protected]> > Subject: Re: [PD] bug in freeverb??? > To: "Matt Barber" <[email protected]> > Cc: [email protected] > Date: Wednesday, 1 July, 2009, 8:22 PM > Hmmm, this sounds like underflow > traps ("denormals"). You should > also be able to add a small constant to the input signal. > > I notice gcc has the option > > -fno-trapping-math > > which may make the problem disappear if my theory is > correct. (I > hope the FPU simply sets underflows quietly to zero when no > trap can > be generated.) > There is also > > -ffast-math > > which is more aggressive. > > - jos > > At 11:30 AM 7/1/2009, Matt Barber wrote: > >We have also had this problem, and have found that > normally one can > >avoid it by salting the [freeverb~] object with a > minuscule amount of > >noise at all times. > > > >Matt > > > > > > > > > Message: 5 > > > Date: Wed, 1 Jul 2009 09:57:43 -0700 (PDT) > > > From: Andres Ferrari <[email protected]> > > > Subject: [PD] bug in freeverb??? > > > To: [email protected] > > > Message-ID: <[email protected]> > > > Content-Type: text/plain; charset=iso-8859-1 > > > > > > > > > when is connected into freeverb any signal > multiplied by zero > > > the CPU usage begin to up and up to the limit, > and if the patch > > is heavy by far exceeds the 100%....sound and > everything becomes a mess. > > > > > > This happens to me only in leopard. > > > > > > In osx 10.4 (ppc) and windows I've never had that > problem. > > > Andr?s Ferrari G. > > > > > > http://www.myspace.com/anfex > > > > > > >_______________________________________________ > >[email protected] > mailing list > >UNSUBSCRIBE and account-management -> > >http://lists.puredata.info/listinfo/pd-list > > > Julius O. Smith III <[email protected]> > Prof. of Music and Assoc. Prof. (by courtesy) of Electrical > Engineering > CCRMA, Stanford University > http://ccrma.stanford.edu/~jos/ > > > _______________________________________________ > [email protected] > mailing list > UNSUBSCRIBE and account-management -> > http://lists.puredata.info/listinfo/pd-list > Send instant messages to your online friends http://uk.messenger.yahoo.com _______________________________________________ Pd-dev mailing list [email protected] http://lists.puredata.info/listinfo/pd-dev
