February 2006 - chuck-users - lists.cs.princeton.edu

Looping Sample Playback
by Mike McGonagle 28 Feb '06

28 Feb '06

Hello all, I was wondering if there is a ugen that will handle arbitrary looping points? I have some samples for various instruments (ie piano, mellotron strings, etc), and would like to hook them up in ChucK. Basically, if the sndbuf ugen is the starting point for this, then do I need to write my own "looping" function to ensure that it gets back to the proper points within the sample. Or has someone already implemented this functionality and would be interested in "sharing"? Thanks, Mike

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Re: chuck-users Digest, Vol 7, Issue 22
by Jim Hinds 28 Feb '06

28 Feb '06

Good analysis. However, from a probablistic viewpoint the time-out problem is vanishingly small for a lightly loaded local network (that's why UDP works very well for machine control applications REF: sixnet protocol). Pretty much give the perfomer the ability to get his files over to the server. If he is really worried about time-outs, the logical thing to do is to structure those chuck scripts to load the needed files prior to starting the sound emitting spork-ettes. Jim On Feb 27, 2006, at 7:29 PM, chuck-users- request(a)lists.cs.princeton.edu wrote: > From: Ge Wang <gewang(a)CS.Princeton.EDU> > Date: February 27, 2006 6:17:59 PM HST > To: ChucK Users Mailing List <chuck-users(a)lists.cs.princeton.edu> > Subject: Re: [chuck-users] file open semantics for clustered chuck > Reply-To: ChucK Users Mailing List <chuck- > users(a)lists.cs.princeton.edu> > > > Hi! > >> Since an important usage mode for chuck is analogous to a server >> for multiple performers, I'd like to suggest that the file open >> semantics be extended. > > Great idea, though there are certainly more issue to consider for > remote operations, since they often aren't always as transparent as > their interface advertises. For example, network timeouts when > retrieving a file need to handled. Actually this seems to be part > of a similar problem of pre-loading/chunking sound files to avoid > interruption on large sound files. So, we should probably add some > options to control load behavior. > >> By simply extending the semantics for Chuck's "open" from >> expecting a file name, I suggest that it be a URL instead. If the >> filename starts with http:// or ftp:// or other legal prefix, give >> the URL to a curl library for access. > > Cool. The .open function already examines the path to catch > "special" internal data (i.e. "special:glot_pop"). It would make > sense to extend that to URL. We just need to find a way to semi- > gracefully deal with potential network timeout and lag. > > Thanks. We shall look into this. > > Best, > Ge!

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Creating Traditional Instrument Sounds Using OSC (ChucK vs. SuperCollider)...
by DANIEL MAGNUSZEWSKI 28 Feb '06

28 Feb '06

All, I hope this is not off topic :-) I have been playing with SuperCollider for a week or two since reading an article on creating live music with Perl code (http://toplap.org/index.php/Hacking_perl_in_nightclubs). Note - I am a programmer (mainly Perl), but quite a newbie with live coding and I know little to nothing about writing ChucK/sclang code. Essentially, there is an editor called feedback.pl (http://cpan.org/authors/id/Y/YA/YAXU/perl-music-article/examples/feedback-0…) that allows you to write Perl code that will create OSC messages that will be sent to SuperCollider. SuperCollider is running the following code (http://cpan.org/authors/id/Y/YA/YAXU/perl-music-article/examples/simple.sc) that, from my understanding, the simple.sc script listens for OSC messages, of which I can send from feedback.pl using built in methods 'play' and 'trigger'. For Example (Perl Code): sub bang { my $self = shift; # play a "middle c" note every fourth bang $self->play({num => 60}) if $self->{bangs} % 4 == 0; } I currently have this working, and I can make some pretty cool "digital" sounding music. What I would like to be able to have these sounds be conventional instrument sounds (Bass, Drums, Guitar, Trumpet, Piano, etc). Is there a way to achieve this through ChucK, or do I need to use a software synth like fluid-synth? I also want to be able to code, execute, and modify this live. Is anyone else doing this? Thoughts? -Dan

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file open semantics for clustered chuck
by Jim Hinds 27 Feb '06

27 Feb '06

Since an important usage mode for chuck is analogous to a server for multiple performers, I'd like to suggest that the file open semantics be extended. When a chuck script is submitted from a performers host to a remotely running chuck server, that script may open files, which must reside on the server file system, not the submitters host. This means that wave files, or other data must be first copied into the server, or otherwise exported. By simply extending the semantics for Chuck's "open" from expecting a file name, I suggest that it be a URL instead. If the filename starts with http:// or ftp:// or other legal prefix, give the URL to a curl library for access. For this to work, the performer's system need only have an httpd or ftpd or ssh deamon running locally to give the remote chuck access to those needed files. As a side effect, the files need only be present "somewhere" out there in cluster land. The URL will rule. Jim Hinds

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string handling
by tim perkis 27 Feb '06

27 Feb '06

hi -- please excuse me if I've missed something discussed here previously, or missing something obvious in chuck at present... but I don't see support for any sort of basic string manipulation. -- is that the case? I understand this is reasonably a low priority in a language for processing sound! -- but it would be nice to have some way to compose strings, perhaps for use in loading/saving text parameter files, or computing strings to be passed to a SYSTEM call... something like an sprintf call? or javascript/python style concatenation operators? like 'There are ' + n_shreds + 'shreds running.' => str; Pardon me if I'm overlooking something already implemented in the language... I'm a newbie T

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ChucK Inconsistencies...
by Mike McGonagle 27 Feb '06

27 Feb '06

This is a list of something that I find to be a little difficult when learning ChucK. Language inconsistencies - I am point these things out, more from a 'linguistic' point of view, not so much as 'bugs'. One syntax about ChucK that I like is that data can come before the function calls that use that data. It just seems to make reading the code much easier. While this can be good for some things, others do suffer. One of those "troubles" is: 0.0 => myFunc; 0.0 => myFloat; it is hard to tell which one of these is really a function call, and which one is an assignment statement, without knowing the full program. And when you start to deal with objects, this might get to be trouble. When using Ugen objects, this is also kind of confusing, as when you are retrieving a value from the object, you use last() => myFloat; but when setting it, you use: myFloat => next; Now onto the specifics... ************************* 1. not all function calls are created equal fun float myFunc0() { return 0.0; } fun float myFunc1(float x) { return 0.0; } fun float myFunc2(float x, float y) { return 0.0; } 0.0 => float x => float y => float z => float a; () => myFunc0; // does not compile, () is not valid in this context x => myFunc1; // valid (x) => myFunc1; // valid (x, y) => myFunc2; // valid ************************* 2. invalid cast to int from function x => myFunc1 $ int => y; // does not compile (x => myFunc1) $ int => y; // does compile ************************* 3. cannot perform '-' on object references... x => myFunc1 - z => a; // does not compile (x => myFunc1) - z => a; // does compile ************************* 4. Library inconsistencies There are many functions in the 'std' library that would fit better (IMHO) in the 'math' library. Is there a particular reason why these functions are in 'std' and not 'math'? Could this be changed (without breaking the world of ChucK)? Any objections? ************************* 5. doesn't work, but no compiler error null @=> Object v; (v == null) ? true : false => int val; <<< v, val >>>; (v == null) ? false : true => val; <<< v, val >>>; ************************* 6. Why would this compile, and not produce an error? What does ChucK do with it internally? Cause trouble? While this is a mistake, ChucKy eats it up like breakfast. I found this will testing something, and mistakenly entered 'public' instead of 'fun'. When I tried to use 'at()', ChucK said "undefined variable/member 'at' in class/namespace 'MyClass'..." 'at()' was defined outside of the class. public float at(time n) { return n / 1::ms; } ************************* 7. You can't use the "ChucK" form when sporking a shred... fun void doit(float s) { } (0.0) => spork ~ doit; // not valid spork ~ (0.0) => doit; // not valid spork ~ doit(0.0); ************************* While some of these are important, I don't expect everything to be addressed. Thanks again to everyone who is working on this, it is wonderful, dispite my "complaints"... Mike

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pointing the ChucK Homepage to the new WIKI
by Mike McGonagle 26 Feb '06

26 Feb '06

Hello Ge, Thanks for all the hard work in getting the WIKI updated. I was noticing that on the home page for ChucK, it still points to the old one. Just thought it might be a good time to update that... Thanks again, Mike

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New WIKI functional
by Adam Tindale 22 Feb '06

22 Feb '06

Hello All, Ge and I have been working for most of the day making the new WIKI functional. Please take a look and make some suggestions. We would love it if you would post some of your code or audio. Also, take a look at the old WIKI and see if we missed anything. We have moved some v1.1.x programs out of the way. If they are yours then maybe could upload your 1.2.x compatible versions. We would like to make the full switch in a day or two. With your help we should be able to do it. NEW http://wiki-new.cs.princeton.edu/index.php/ChucK OLD http://wiki.cs.princeton.edu/index.php/ChucK --art

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Chucking scores
by Pedro Lopez-Cabanillas 21 Feb '06

21 Feb '06

Hi all, I've written a little article on the subject, that you can find here: http://www.telefonica.net/web/plcl/chuck/ There are also some merry melodies for ChucK. Hope you enjoy it. I would like to hear your opinion about everything, the music, the proposal, and the wording. Sorry for my poor English, BTW. Regards, Pedro

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wiki upgrade and transfer
by Ge Wang 21 Feb '06

21 Feb '06

Hello again, Our ever-hardworking system staff has upgraded the wiki to a new version of mediawiki and also added more rigorous measures to prevent spammers from defacing the wiki. The upgraded wiki is temporarily at: http://wiki-new.cs.princeton.edu/ http://wiki-new.cs.princeton.edu/index.php/ChucK The existing wiki will remain at the current URL until we make the switch: http://wiki.cs.princeton.edu/ http://wiki.cs.princeton.edu/index.php/ChucK The new wiki requires one to be logged in before he/she can edit a page. Furthermore, the registration page now has a CAPTCHA feature to help prevent bots. I guess this would be a good time to start moving contents from the old wiki to the new and doing some housecleaning. 1. I think the <pre> tags now work, but it may be better to denote code by inserting spaces before each line, like in the page: http://wiki.cs.princeton.edu/index.php/FractalMelody 2. Some or maybe most of the page could use some organizing and updating. Perhaps the ChucK_Programs page can benefit from some basic categorization. 3.The upload feature seems to be enabled for now, though I am not sure if this will be permanet. I will find out. 4. We will switch over to the new wiki probably early next week. (just the URL change from wiki -> wiki-old, and from wiki-new -> wiki) 5. Use the talk page to avoid collisions on edit. The talk page is accessible via the 'discussion' link on the top. Ready? Everyone of course is invited to contribute. Adam T. and Mike M. might want to coordinate this? Best, Ge!

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