hello,

I had a look at a modalys-help.pd file. It appear that modalys is not 
implemented as a pd abstraction, but as a compiled object. I may be wrong, but 
I think this object use modalys file that define all material / shape / 
exitator / etc. So it's quite useless without the full modalys software.

anyway, in order to add my piece of answer to the original question:
about 20 years ago I  made my master degree about a bow / string interaction 
using a fake motorized bow and a virtual string.
2 different strings where implemented :

-The 1st sting was made using virtual 1D mass, spring and damper in a linear 
arrangement, just like a spacial discretisation of a real string. This result 
of incorrect tuning of high harmonics of the virtual string (regarding a real 
string)

-The 2nd string was made using something also named "modal synthesis" (but very different 
from modalys) : it was "just" mass/spring/damper 1D resonator connected together, a bit 
like the paper initially send in this thread.

Since modalys use matrices, I guess that it use more complex interaction 
between elements than a simple spring/damper interaction like I use to do. This 
result in being able to also simulate the shape of the vibrating structure.

Anyway, about 15 years ago I start the pmpd library (physical modelling for 
pure data) that provide simple mass / spring / damper simulation. The pmpd~ 
object allow this kind of simulation at audio rate. There is an example of the 
1st kind of string simulation. The 2nd string can also be implemented thanks to 
this object, but I did not provide any example since I miss the way to tune the 
model.

pmpd~ provide only simple interaction, so I don't use it any-more. I use the 
pmpd object that is lot's more complex (but works only at data rate) and a 
simple hack to compute audio data. There is also an example in the library 
distribution.

if you are interested, you can try pmpd using apt-get or deken on linux. I know 
that Nicolas Montgermont compile pmpd for osX, so a recent binary exist 
somewhere. I have no idea about recent build for windows.

cheers
C



Le 06/08/2017 à 21:58, Jean-Marie Adrien a écrit :
would be great if it would be in pd abstractions !
everything is in the paper though, you are right, and the method is incredibly 
powerful, so the project was in that time to control it with gestures data 
bases and artificial intelligence and so on, all of this being existing now, 
not speaking about multi channel sound diffusion etc.
I was disappointed when, after having developed the method at IRCAM, i 
discovered (and had to pay for it though) some ten years ago the actual modalys 
thing that was kind of retro engineered after i left IRCAM, from the big C++ 
initial software with was developed between 1984 and 89.

The math is not so complex, it is just a matrix equation incremented step by 
step, and very straightforward and intuitive discontinuities in time domain 
which correspond to straightforward updates of the matrix, resulting for 
instance from contact between objects and other intuitive events.
If you simplify the maths, it will probably become more complex i’d say, and 
you will probably hear it, because time domain sound synthesis is quite 
sensitive.

On the same line, one advantage of modal synthesis is that you can achieve 
impossible physical excitations on imaginary structures, and interpolate 
between all this, having transient sounds and articulations, but even with the 
full math though, you could hear in that case that you were sort of tearing the 
equations, which corresponds to the fact that there is no existing physical 
gesture which you could refer to when exploring impossible configurations.
Math simplification is what happened probably when the available pd modalys 
software was achieved : i was disappointed by this tool and rarely use it.
Another application has been developed by Apple in Logic with the "sculpture » 
plugin : it is very much main stream, they probably make money with it and Im still 
poor. Bref.

I’d love the true vintage thing on pd now : it is just implementing a matrix 
equation with updates conditions.
The point is that, thirty years later, i do not understand anymore a single 
line in C++, although I’ve written many thousands of lines.
Hmm. I dont believe it myself, how is this even possible ?  But i remember very 
well the principles. Id be happy to help if i can anyway.
jm


Le 6 août 2017 à 16:50, Jesse Mejia <jme...@anestheticaudio.com> a écrit :

Yes - I mentioned Ircam's Modalys and that  paper in my initial post. Because 
modal synthesis is so well known, and well documented, I'm surprised there 
isn't a similar (but free!) pd implementation. Something with abstractions 
instead of externals would be great.

So let's make one. I know it's a bank of resonant bandpasses, but working out 
their relationships based on the modal characteristics of physical shapes seems 
to be key, and abstracting those relationships to friendly controls.

The math in the papers is a bit beyond me but it looks like it's all there. I 
can't tell by looking at it if it's something that would be too hard/annoying 
to do with vanilla.. or if it's describable in a less math heavy way.

Alex - newly compiled versions of the stk would be great! I tried and failed at 
that about a year ago. But the faust implementations compile well from faust to 
pd.

On Aug 6, 2017, at 3:24 AM, cyrille henry <c...@chnry.net> wrote:



:)
indeed and i had myself to _pay_ for it, which is something that probably illustrates the 
"élégance à la française"
jm

I did not encourage piracy, but since pd patch can't be protected I guess that 
an anonymous source could leak the files without any trouble.

cheers
c

_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> 
https://lists.puredata.info/listinfo/pd-list


_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> 
https://lists.puredata.info/listinfo/pd-list



_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> 
https://lists.puredata.info/listinfo/pd-list

Reply via email to