October 2009 - chuck-users - lists.cs.princeton.edu

problems using quicktime synth
by David Minor 11 Oct '09

11 Oct '09

I can't seem to get Chuck to play out of the built-in QT synth on Mac OSX. I turned on the IAC driver and I see my events being picked up there. I also checked in MidiShare that the IAC driver is routed to the QT synth. Still nothing! Other applications that output to the built-in midi synth seem to work. Regards, David

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instrument in function - good idea, or?
by Atte Andre Jensen 09 Oct '09

09 Oct '09

Hi I know I'm a bit slow, but I just found that it's quite simple to totally encapsulate an instrument in a function, ugens and all, as the example below shows. Now I'm wondering how much overhead this yields compared to keeping the ugens, ADSR.set and stuff like that outside the function? I guess part of the answer is it depends on what one needs to do. Do you need to play the instrument monophonically, with a small, fixed number of voices or ad-hoc polyphony. The instrument-in-a-function solution elegantly solves the polyphony problem, I can just spork as many voices as I need, and they are automatically destroyed when finished. But how great a peak in cpu usage does the creation of the ugens generate? 5 => int octave; .1 => float gain; [0,2,4,7,9,11,14,16] @=> int notes[]; while(true){ notes[Std.rand2(0,notes.cap()-1)] + 12*octave => int note; ms * Std.rand2f(1500,2000) => dur length; spork ~ ep(note, length, gain); ms * Std.rand2f(150,1500) => now; } fun void ep(int note, dur length, float gain){ 2::second => dur decay; 10::ms => dur release; SinOsc s1 => ADSR e1 => dac; SinOsc s2 => ADSR e2 => dac; gain => s1.gain; gain * .2 => s2.gain; e1.set(1::ms, decay, 0, release); e2.set(1::ms, decay * .3, 0, release); Std.mtof(note) => s1.freq; s1.freq() * 2=> s2.freq; e1.keyOn(); e2.keyOn(); if(length < decay){ length => now; e1.keyOff(); e2.keyOff(); release => now; } else { decay => now; } } -- Atte http://atte.dk http://modlys.dk http://virb.com/atte

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1.2.1.3 (dracula) unleashed!
by Ge Wang 06 Oct '09

06 Oct '09

Dear all, chuck-1.2.1.3 (dracula) is available: http://chuck.cs.princeton.edu/ http://chuck.stanford.edu/ This release, long overdue, introduces experimental/initial support for file I/O (thanks to many folks who have contributed, including Andrew Schran and Martin Robinson, both of whom have provided much implementation and design). Along with the file I/O functionality comes several new languages features and special objects, including using => and <= (the "back-chuck" operator, as Spencer calls it), as well as chout (stdout, pronounced "shout") and cherr (stderr, pronounced "Cher"). Additionally, a few of function overloading and other issues from the chuck-users list have been resolved (hopefully). As always, please let us know of any bugs/features you encounter! (Please see the release notes at the end of this email.) Many many thanks once again to Kassen, Inventor, and everyone on chuck-users, as well as the electro-music chuck forum, PLOrk, SLOrk, folks at Smule, Fernando Lopez-Lezcano, Carr Wilkerson, Chris Chafe, Andrew Schran, Martin Robinson, and the rest of the chuck community for making this release happen! Thanks and Happy ChucKing, UpChucKing! Best, Ge + Spencer, on behalf of entire chuck team VERSIONS --- 1.2.1.3 - (added) initial/experimental support for file I/O (finally) (thanks to Andrew Schran, Martin Robinson) - (added) new class: IO, FileIO see examples/io/: read-int.ck read-str.ck readline.ck - using readline write.ck - write using <= write2.ck - write using .write() - (added) IO input via => - (added) IO output via <= (the "back-chuck") example: fio <= x <= " " <= y <= "\n"; - (added) new syntax for checking if/while/for/until with IO objects e.g., while( fio => i ) { ... } - (added) StdOut/StdErr objects: "chout" (pronounced "shout") "cherr" (pronounced "Cher") - (added) Hid.open() now can accept a device name parameter - (added) analysis/tracking examples are now back (thanks to Kassen for looking into this) - (fixed) calling overloaded functions with most specific match e.g., Specific extends General: fun void foo( General obj ) { } fun void foo( Specific obj ) { } foo( obj $ Specific ); // should call foo( Specific ) (thanks to Robert Poor for reporting, to Kassen, David Rush, Michael Heuer, and Andrew C. Smith for follow-up) - (fixed) STK instruments control changes reports range issues as "control value exceeds nominal range"; previously printed hard-coded values that were potentially misleading (thanks to Kassen for reporting) - (fixed) all oscillators now produce audio for negative frequencies (thanks to Luke Dahl) - (fixed) incorrect UGen disconnect (thanks Kassen for reporting) - (fixed) type checker now validates if/while/for/until types - (fixed) linux compilation (for gcc 4.x) - (fixed) complilation on OS X Snow Leopard ~~~ Ge Wang Assistant Professor Center for Computer Research in Music and Acoustics (CCRMA) Stanford University http://ccrma.stanford.edu/~ge/ ~ Co-founder, CTO, Chief Creative Officer Smule http://www.smule.com/ ~ http://twitter.com/gewang ~~~

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expanding paths
by Atte Andre Jensen 05 Oct '09

05 Oct '09

Hi Consider the following: "~/music/samples/seq/beats/bar_matched/spending.wav" => sample; //"/home/atte/music/samples/seq/beats/bar_matched/spending.wav" => sample; SndBuf s => dac; s.read(sample); This will yield an error [chuck](via SndBuf): cannot stat file '~/music/samples/seq/beats/bar_matched/spending.wav'... It seems chuck doesn't like the tilde (~), which on linux (I suppose osx too) is standard for "the current users home directory" in my case "/home/atte/. Are there any good advise for solving this in .ck-code or should I see if I could hack it in the source? -- Atte http://atte.dk http://modlys.dk http://virb.com/atte

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release 1.2.1.3: time (still) goes backwards
by Robert Poor 05 Oct '09

05 Oct '09

Ge (and everyone): I'm very excited about the new 1.2.1.3 release, and will dig more deeply into it this week. And like everyone else, I threw my favorite bug tests at it. One bug -- "time goes backwards" -- lingers. But the new release goaded me into creating a minimal test case that shows the problem. The real issue is that the scheduler gets confused about durations (or times) with fractional samples. So below is the test file. It's heavily commented, but the actual number of lines of code is small. Does anyone want to test this on a Windows or Linux build? Enjoy... - Rob Poor // ================================================================ // File: fractional_time_test.ck // // Summary: test file to demonstrate ChucK timing bug. // Applies to: chuck version: 1.2.1.3 (and earlier) // Submitted by: Robert Poor <rdpoor(a)gmail.com> // // Details: Chuck's scheduler does not properly handle times with // non-zero fractional parts. In general, a shred that waking from an // event always sees 'now' with a fractional part of 0. This has two // distinct manifestations: if 'now' had a fractional part of less // than or equal to 0.5 sample, in a waking shred, now is truncated to // the nearest integer sample. If now had a fractional part greater // than 0.5 sample, then the shred will fail to run until now advances // to the next higher sample, even if yield() is called in the // triggering shred. // // Executing this file following code produces this output: // ================================================================ // bsh% chuck --version // // chuck version: 1.2.1.3 (dracula) // exe target: mac os x : powerpc // http://chuck.cs.princeton.edu/ // // bsh% chuck --audio fractional_time_test.ck // 1.000000 0x5e7160 waiter: okay // 1.000000 0x5e5fd0 step: okay // 2.000000 0x5e7160 waiter time: expected 2.300000 but found 2.000000 // 2.300000 0x5e5fd0 step: okay // 3.600000 0x5e5fd0 step trigger count: expected 3 but found 2 // 4.000000 0x5e7160 waiter time: expected 3.600000 but found 4.000000 // bsh% // ================================================================ Event trigger; // trigger to signal waiter() int triggered_count; // # of times waiter() has run time triggered_time; // time at which trigger.broadcast() called spork ~ waiter(); // start the waiter shred // save some preset times. now + 1.0::samp => time t0; now + 2.3::samp => time t1; now + 3.6::samp => time t2; // t0 = 1.0 sample. this works normally: step() waits until now==1.0, // broadcasts on the trigger event and yields. waiter() then runs at // the expected time. step(t0); // t1 = 2.3 sample. this fails: step() waits until now==2.3, // broadcasts on the trigger event and yields. waiter() then runs, // but when it runs, 'now' is set to 2.0: time has gone backwards. step(t1); // t2 = 3.6 sample. this fails: step() waits until now==3.6, // broadcasts on the trigger event and yields. however, waiter() // fails to run until now has advanced past 4.0 step(t2); // make sure everything runs before we quit 1::second => now; fun void step(time t) { t => now; // wait for the designated time now => triggered_time; // record wake time triggered_count+1 => int i; // record expected trigger count trigger.broadcast(); // trigger the waiter() shred me.yield(); // ... and give it time to run // verify that the waiter() shred actually ran if (triggered_count != i) { <<< now, me, "step trigger count: expected", i, "but found", triggered_count >>>; } else { <<< now, me, "step: okay" >>>; } } fun void waiter() { while (true) { trigger => now; // wait for trigger.broadcast() / me.yield() triggered_count++; // prove that this shred has run // verify that 'now' agrees with expected wake time if (now != triggered_time) { <<< now, me, "waiter time: expected", triggered_time, "but found", now >>>; } else { <<< now, me, "waiter: okay" >>>; } } } // EOF

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playing raw audio files
by Renato Fabbri 05 Oct '09

05 Oct '09

Hi List, I didnt figure out how to read/play raw audio files in chuck, and didn't find any doc either. say i want to read a mono "rawsound.raw" as 16bit samples and 8kHz sample rate (say playback sample rate is determined beforehand). Is there a way to read and play such a raw audioo data or should i need to convert to wav or similar? best, rf

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serfault under arch (again) + profiling
by Atte Andre Jensen 05 Oct '09

05 Oct '09

Hi I hit the wall (cpu/chuck performance wise) again, and thought I'd profile chuck with gdb, in the unlikely event something lands in my lap :-) However, I then realized that the chuck I build under arch is segfaulting (have been mentioned here before). So I have two questions: 1) Could anyone help me (and arch users) with getting chuck to run under arch? Some info would be: gcc version 4.4.1, jackdmp version 1.9.2, chuck version 1.2.1.2. I don't know what else to provide, I'll gladly supply all the information needed :-) 2) Has anyone done any profiling or attempts to get chuck to run more efficiently? Are there any work being done in this area? What about the new release (Ge spoke about it a few days ago)? Is there any improvements in there? -- Atte http://atte.dk http://modlys.dk http://virb.com/atte

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New FileIO options, broken stuff from CVS: FileIO.read(int)
by Andrew C. Smith 05 Oct '09

05 Oct '09

Dear List (mostly Ge & other people who know about the brand-new dracula) First of all, great new ChucK. The FileIO is great to have, and it's good to see it implemented fairly comprehensively. I like how FileIO.readInt() or readFloat() just becomes FileIO => (int), too. Anyway, I was previously using FileIO.read(int) in my Scala file importer to parse a line and look for a "/" after the first integer (making it a ratio, rather than cents). There doesn't seem to be a FileIO.read method around anymore, though, which makes some sense since readInt and readFloat aren't used now. I was going to wade back through the source, which is where I found read(int) in the first place, but thought I should at least let you all know that the method was being used. Are there any good alternatives to .read()? My issue with reading in a string was that there's no space between the number and the "/" in Scala files, so it would read as one long string. Then, parsing the string into multiple bits, all that sort of thing...really difficult. My method was to read in a float, look for a "/" (with .read(1) == "/" ), and if it found one read in another float and calculate the ratio; if it didn't find one, calculate it as musical cents. Thanks for the help. Best, Andrew

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Passing classes to functions
by Adam Tindale 04 Oct '09

04 Oct '09

Hi All, I was doing some work and created some bugs that I ironed out when I discovered something: when non-primitive types are passed to functions they are passed by reference and not by value! I include a test so you can see what I mean. I hope somebody find this useful. --art class test{ 0 => int val; } test obj1; // obj2 is a reference to obj1 test obj2 @=> obj1; <<< obj1.val , "original object">>>; <<< obj2.val , "reference to original">>>; 2 => obj2.val; <<< obj1.val , "original object">>>; <<< obj2.val , "reference to original">>>; fun void testclasspassing(test i) { <<< i.val, "in function" >>>; } testclasspassing(obj1); testclasspassing(obj2);

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forward reference oddity
by Robert Poor 02 Oct '09

02 Oct '09

Here's another oddity. The following file: --------------------------------------- // file: ouroboros.ck class Ouro { Boros @ boros; fun void set_boros(Boros boros) { <<< this.toString(), "set_boros(", boros.toString(), ")" >>>; boros @=> this.boros; } } class Boros { Ouro @ ouro; fun void set_ouro(Ouro ouro) { <<< this.toString(), "set_ouro(", ouro.toString(), ")" >>>; ouro @=> this.ouro; } } --------------------------------------- gets a compile-time error: --------------------------------------- r% chuck ouroboros.ck [ouroboros.ck]:line(5): class 'Boros' has no member 'toString' [ouroboros.ck]: ...in function 'set_boros' --------------------------------------- This is odd, since (AFAIK) toString() is defined on the Object class, and all classes inherit from Object. If I remove the toString() call on boros as below, it compiles without error. Note chat ChucK has no problem compiling ouro.toString() in function 'set_ouro': --------------------------------------- // file: ouroboros.ck class Ouro { Boros @ boros; fun void set_boros(Boros boros) { <<< this.toString(), "set_boros(", boros, ")" >>>; boros @=> this.boros; } } class Boros { Ouro @ ouro; fun void set_ouro(Ouro ouro) { <<< this.toString(), "set_ouro(", ouro.toString(), ")" >>>; ouro @=> this.ouro; } } --------------------------------------- Is this because Boros is a forward reference? And is this not a bug? - Rob

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