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

problem with osc over network
by Bozelos Dimitris 14 Mar '09

14 Mar '09

Hi all, I'm working on a group project and I chose to use chuck not having "chucked" at all before. So we need to send / receive osc messages over the network with the other groups members and i've run into some problems, I don't receive the messages other people send me. I can send messages with chuck succesfully and receive successfully with supercollider. So there is no problem with the network / firewall. Here is my code for receiving: OscRecv recv; 6449 => recv.port; recv.listen(); recv.event( "/address, f" ) @=> OscEvent @ oeFloat; float k; while( true ) { oeFloat => now; while( oeFloat.nextMsg() ) { oeFloat.getFloat() => k; <<<k>>>; } 1000::ms => now; } Is there anything that I miss? This code works fine at localhost (from a chuck shred to another). The other people are sending messages with Max/MSP and SuperCollider, can this cause problems? Can there be a mismatch of the type of the incoming message with what is expected? Although I was sure while testing that the message from Max/MSP was sent as a float, can this be a problem somehow? Any thoughts would be appreciated, Dimitris ___________________________________________________________ Χρησιμοποιείτε Yahoo!; Βαρεθήκατε τα ενοχλητικά μηνύματα (spam); Το Yahoo! Mail διαθέτει την καλύτερη δυνατή προστασία κατά των ενοχλητικών μηνυμάτων http://login.yahoo.com/config/mail?.intl=gr

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cross-referenced classes?
by Robert Poor 13 Mar '09

13 Mar '09

Assume I have the following: ===== file: scratch.ck ===== public class Scratch { Sniff _sniff; } ===== EOF ===== ===== file: sniff.ck ===== public class Sniff { Scratch @ _scratch; } ===== EOF ===== How does one compile cross-referenced classes? Neither "chuck scratch.ck sniff.ck" nor "chuck sniff.ck scratch.ck" bring joy. (There's a similar question for any class that has a reference to itself as a member, such as a linked list. But I'll save that question for the next time I need to flaunt my ignorance.) - Rob

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iterating over an associative array?
by Robert Poor 12 Mar '09

12 Mar '09

How does one iterate over an associative array in ChucK?

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Bad return signature in pre-constructor leads to null instance
by Robert Poor 12 Mar '09

12 Mar '09

Got a bug for the team. Don't ask me how long it took me to track it down. Consider this code and the effect of running it: ============== public class Foo { bad_pre_constructor(); fun float bad_pre_constructor() { <<< "bad_pre_constructor, this =", this >>>; } } Foo bad_foo; <<< bad_foo =", bad_foo>>> ============== % chuck foo.ck bad_pre_constructor, this = 0x634720 bad_foo = 0x0 ============== Note that the instance of bad_foo is null. Now consider this code: ============== public class Foo { good_pre_constructor(); fun void good_pre_constructor() { <<< "good_pre_constructor, this =", this >>>; } } Foo good_foo; <<< good_foo =", good_foo>>> ============== % chuck foo.ck good_pre_constructor, this = 0x634720 good_foo = 0x634720 ============== Note that the instance of good_foo is a reasonable non-null value. Did you spot the difference? "bad_pre_constructor" is declared (improperly) to return a float, but it doesn't, and an instantiation of Foo silently returns a null. "good_pre_constructor" is properly declared with a void return, and an instantiation of Foo returns a good value. So yes, this was operator error -- it's an error not to return a value when you claim you're going to. But ChucK fails silently, at least until you get hit with a NullPointerException some time later in the execution. This is not friendly behavior. - Rob P.S.: Uh, is this the right forum for reporting bugs like this?

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benchmarking UGens
by Atte André Jensen 12 Mar '09

12 Mar '09

Hi We all know that chuck is not the fastest audio software out there. But I guess like me you've all found ways to work around that. I often found myself wondering "how much can I save by disconnecting this UGen" or "exactly how expensive is another NRev". For this purpose I started to do some benchmarking in the form of a bunch of .ck files and a bash script. My initial results are here: http://atte.dk/chuck/results.txt The first line is "chuck --loop", so the wm alone. "nb" is the number of files, "cpu" is the cpu usage as reported by htop on my laptop (2Ghz Intel dualcore), and "cpu normalized" is cpu-usage (simple multiplication) at nb=100. Of course this doesn't make sense without seeing the .ck files, so I've put them here: http://atte.dk/chuck/performance_tests.tgz I'm quite aware of that this approach is very un-scientific, so any input on how to improve it is more than welcome. Esp. I'm wondering how 10 * PRCRev = 7% and 50 * PRCRev = 46% (should have been 35%). I'm gonna continue my tests, but you're all welcome to supply files for testing. Maybe this should all end up on the wiki? NB: This is in no way a critique of the developers. Sure I would love to see a faster chuck, but we still love it and use it. -- Atte http://atte.dk http://modlys.dk

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popBack() bug?
by mike clemow 02 Mar '09

02 Mar '09

Hey all, I'm pretty sure that popBack() is broken: class Stack { string stack[0]; fun void push( string s ) { stack << s; } fun string pop() { stack[stack.size()-1] => string s; //stack.popBack(); // comment this out and it works... return s; } } Stack stack; stack.push( "five" ); stack.push( "six" ); <<< stack.pop() >>>; <<< stack.stack[0] >>>; --- This will crash with this error: chuck_oo.cpp:114: failed assertion `m_ref_count > 0' Abort trap Anyone else run into this? -Mike -- http://michaelclemow.com http://semiotech.org

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negative zero
by Robert Poor 01 Mar '09

01 Mar '09

I'm troubled by ChucK's handling of negative zero. A variable set to -0.0 is indistinguishable from a variable set to 0.0, except in printing. This is not a problem in everyday practice, but it seems likely that it will cause trouble when you pass to an external program. [Why would you set a variable to -0.0 in the first place? Try this: (-3.0 % 1.0) => float bar;] Comments? ==================== 0.0 => float foo; -0.0 => float bar; // even though foo and bar print differently... <<< "foo = ", foo, " bar = ", bar >>>; // in ChucK's eyes, they are both considered to be zero... <<< "sgn(foo) = ", Std.sgn(foo), " sgn(bar) = ", Std.sgn(bar) >>>; // and they are equal... if (foo == bar) { <<< "equal" >>>; } ==================== produces ==================== % chuck test.ck foo = 0.000000 bar = -0.000000 sgn(foo) = 0.000000 sgn(bar) = 0.000000 "equal" : (string) ====================

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converting from dur to float
by Robert Poor 28 Feb '09

28 Feb '09

Is there truly no way to cast from a dur to a float? I'm writing a sketch of a TapTempo object. It measures the duration between events to estimate a tempo (in my case, expressed in Hz), which of necessity means *somewhere* I need to convert from a dur to a float. But I haven't figured out how to do that. Suggestions? - r

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small note on LiSa.feedback()
by Kassen 26 Feb '09

26 Feb '09

Dear Dan, readme_LiSa2.ck lists; // mylisa.feedback(float); set feedback amount [0,1] for recording As far as I can tell it takes numbers larger than this as well as negative ones; -------8<-------------- LiSa l => dac; -5.0 => l.feedback; <<<l.feedback()>>>; -------------8<-------------- Amounts with a magnitude of over 1 may be unpractical/dangerous but since we will potentially be dealing with a especially perverted (and interesting!) form of Karplus Strong here I feel the option to use negative number here is rather relevant. Yours, Kas.

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Re: [chuck-users] Introducing the KNoW Wave Generator
by Les Hall 23 Feb '09

23 Feb '09

Sounds very interesting, especially the beginning. After a while my own pattern recognition kicks in and it becomes a bit predictable. I wonder if you could use your boolean walker to generate more dynamics in the storyline, to make it more expressive, or to have more distinction between rhythmic parts and freeform. I must say I never heard of No Wave before, so perhaps this makes no sense in this genre. Arthur Hi Arthur, Yes, its all in how you code the logic matrix of the boolean sequencer. What I'm doing is drawing a diagonal line in the matrix with a decreasing probability of ones as you move away from the line. It looks like this: 0 0 0 0 1 1 1 1 0 1 0 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 0 1 0 0 1 1 0 1 1 0 1 0 0 0 1 0 1 1 1 1 0 1 1 0 1 0 1 1 1 1 0 1 1 0 0 0 0 1 0 1 1 1 0 1 0 0 0 0 1 1 1 1 0 0 0 1 0 0 1 1 1 0 1 0 1 0 0 1 0 0 0 1 0 1 1 0 0 1 0 0 1 1 0 1 1 1 1 0 0 1 1 0 0 0 1 1 1 0 0 1 0 0 0 0 1 0 1 1 0 0 1 1 1 1 0 0 1 0 If you stare at that matrix a little while you'll see the diagonal line from lower left to upper right of greater ones density, plus plenty of random bits strewn about. I suppose that much randomness is what makes it seem predictable. It's predictably unpredictable. But I can write code that makes other kinds of boolean sequencer logic matrices. In the past, in my soft synthesizer that has one of these as an array of MAUI buttons, I have had good results drawing circles, lines, and triangles. I was able to make some good rock guitar riffs that way. Actually the randomness is intentional for No Wave, which is supposed to be composed of a mix of wandering notes and hard driving rhythms. But for something else you wouldn't want so many bits strewn about in the logic matrix. So yes, coding the matrix in different ways will give completely different results. Les (Inventor)

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