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dac.channels
by eduard 30 Nov '07

30 Nov '07

Hi there, I'd like to use all my soundcard outputs, however dac.channels() reports the wrong number or at least a different number of channels than chuck --probe. Here's the output of the latter for the mentioned soundcard: [chuck]: ------( chuck -- dac4 )--------------- [chuck]: device name = "RME: Fireface 400 (4AF)" [chuck]: probe [success] ... [chuck]: # output channels = 18 [chuck]: # input channels = 18 [chuck]: # duplex Channels = 18 [chuck]: default device = YES [chuck]: natively supported data formats: [chuck]: 8-bit int [chuck]: 16-bit int [chuck]: 24-bit int [chuck]: 32-bit int [chuck]: 32-bit float [chuck]: 64-bit float [chuck]: supported sample rates: [chuck]: 32000 Hz [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 88200 Hz [chuck]: 96000 Hz [chuck]: 176400 Hz [chuck]: 192000 Hz however dac.channels() reports that only 2 channels are available. I've double checked that this soundcard is the default one and also run chuck with --dac4 flag, but no luck. Does anyone know what could be wrong? thanks in advance, eduard

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Unit tests, vm crashes
by Michael Heuer 29 Nov '07

29 Nov '07

Sorry, should have changed the subject line Michael Heuer wrote: > A few more language questions/feature requests: > > I see that NullPointerExceptions are thrown in some situations (but > not always, see below) by the vm -- is it possible to throw an > Exception? > > Is it possible to catch an Exception? > > I could simulate throwing an exception by printing out an error > message with the offending line number and calling me.exit() . . . is > it possible to get the current line number? > > In my attempt at an unit test framework for ChucK I crash the vm where > I would expect it to throw a NullPointerException. See commented out > lines in the attachment at > > http://electro-music.com/forum/viewtopic.php?p=154598#154598 > > michael >

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upchuck: a chuck preprocessor
by Scott Wheeler 29 Nov '07

29 Nov '07

Since I do a lot of OO-ish stuff in ChucK and tend to reuse my standard classes a lot, the lack of an import mechanism or preprocessor was getting on my nerves. I hacked up a (not-entirely-so-) quick one last night in Perl. The only preprocessor command supported at this point is "include". The syntax is: #include(Something.ck) or, to make things prettier: #include(Something) It will automatically search the current working directory, check to see if appending a ".ck" helps, and then do the same for every directory in the colon separated $CHUCK_DIRS. Extra credit is that it: - Checks to avoid double includes, recursive includes, etc. - Automatically passes all non-file arguments on to ChucK - Translates error messages back to the original files (rather than the temp file that ChucK actually executes; this was a pain since ChucK uses stderr for output and errors) So, let's play with it a little. I've attached a couple of small files to be put in ~/ChucK. I've got upchuck in ~/bin, which is in my path. Then from the shell: export CHUCK_DIRS=~/ChucK upchuck Quux "Foo" : (string) "Bar" : (string) "Baz" : (string) This won't work on Windows, but I suspect the only thing that needs to be reimplemented is the tempName subroutine (which you could just write in Perl in about 2 minutes -- I just don't know what the standard temp dir is on Windows). -Scott #!/usr/bin/perl use strict; use IPC::Open3; use Cwd 'abs_path'; use File::Basename; ################################################################################ # addOutputLine ################################################################################ our @lineMap; our @fileMap; sub addOutputLine { my $file = shift(@_); my $line = shift(@_); push(@lineMap, $line); push(@fileMap, $file); } ################################################################################ # tempName ################################################################################ sub tempName { my $temp = `mktemp -t chuck.XXXXX`; chomp($temp); return $temp; } ################################################################################ # findFile ################################################################################ sub findFile { my $file = shift(@_); (-e $file) && return $file; (-e "$file.ck") && return "$file.ck"; my @dirs = split(":", $ENV{"CHUCK_DIRS"}); foreach my $dir (@dirs) { (-e "$dir/$file") && return "$dir/$file"; (-e "$dir/$file.ck") && return "$dir/$file.ck"; } return ""; } ################################################################################ # include ################################################################################ sub include { our %includes; my $file = shift(@_); my $found = findFile($file); if(length($found) == 0) { die "Could not include \"$file\""; } $file = $found; if(++$includes{$file} > 1) { return ""; } my $output; open(INCLUDE, $file); my @lines = <INCLUDE>; close(INCLUDE); my $count = 1; foreach my $line (@lines) { $output .= &preprocessor($line); addOutputLine($file, $count++); } return $output . "\n"; } ################################################################################ # preprocessor ################################################################################ sub preprocessor { my $input = shift(@_); if($input !~ /^\s*#/) { return $input; } chomp($input); my $command = $input; my $argument = $input; $command =~ s/^\s*#(\w+).*/$1/; $argument =~ s/.*$(.+)$.*/$1/; if($command =~ /include/i) { return include($argument); } die "Unhandled preprocess command, \"$input\""; } ################################################################################ # errorAdjuster ################################################################################ sub errorAdjustor { my $temp = shift(@_); my $error = shift(@_); if($error =~ /^\[$temp\]:line/) { chomp($error); my $lineNumber = $error; $lineNumber =~ s/\[$temp\]:line$([0-9]+)$.*/$1/; $error =~ s/$temp/$fileMap[$lineNumber - 1]/; $error =~ s/line$$lineNumber$/line($lineMap[$lineNumber - 1])/; return "$error\n"; } return $error; } ################################################################################ # main ################################################################################ my $temp = tempName(); open(OUTPUT, ">$temp"); my $command = "chuck"; while(my $arg = shift(@ARGV)) { if(!findFile($arg)) { $command .= " $arg"; } else { print OUTPUT include($arg); } } close(OUTPUT); $command .= " $temp"; if(fork() == 0) { sleep(1); unlink($temp); } else { local(*WRITE, *READ, *ERROR); my $pid = open3(\*WRITE, \*READ, \*ERROR, $command); if(fork() == 0) { my $file = basename($temp); while(my $line = <ERROR>) { print errorAdjustor($file, $line); } } else { while(my $line = <READ>) { print $line; } } waitpid($pid, 0); wait(); } wait(); #include(Foo) <<< "Bar" >>>; #include(Foo) #include(Bar) #include(Baz) #include(Bar) <<< "Baz" >>>; <<< "Foo" >>>;

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[off-list] parab0xx in Wired News
by AlgoMantra 28 Nov '07

28 Nov '07

Hey Guys, We didn't use ChucK in this one, but you can using OSC! I have used Python, and released the source too. Check out the story, and please feel free to embellish and improve upon the code for your own evil purposes. I'm also happy to look at collaborative opportunities/ideas. The code is at my website (see below). We made it to Wired! Yay! http://blog.wired.com/music/2007/11/video-prototype.html ------- -.- 1/f ))) --. ------- ... http://www.algomantra.com

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Sample Playback Efficiency
by Juan-Pablo Caceres 28 Nov '07

28 Nov '07

Dear list, Lets say I have an array of SndBuf, and I want to playback one of the samples each time. What is the most efficient way? What I am doing is just connecting everything to dac, and then setting all but one of the gains to non-zero, something like this: SndBuf buf[20]; for ( 0 => int i; i < 20; i++ ) { sample_names[i] => buf[i].read; //assuming I have an array of //string names buf[i] => dac; 0. => buf[i].gain; } //then to playback one at the time: int isamp; while (true) { Std.rand2(0, 19 ) => isamp; 0 => buf[isamp].pos; 0.1 => buf[isamp].gain; //set gain to something different // than zero 200::ms => now; 0. => buf[isamp].gain; //bring it back to zero } This works, but doesn't feel right. All the DSP connections are made, so I would guess this is inefficient. The other option will be to connect (=>) and disconnect (=<) dynamically but that solution also feels wrong... Any ideas? Thanks so much again, Juan-Pablo

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ChucK on OLPC??
by M. Edward (Ed) Borasky 27 Nov '07

27 Nov '07

Forgive me if this is a FAQ, but has ChucK been ported to the XO laptop (One Laptop Per Child)? I'm seriously considering getting one under the Give One Get One program, and it appears to have CSound on it already. I'm thinking a bunch of them with the built-in wireless would make a nice laptop orchestra. :)

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debug print duration
by Juan-Pablo Caceres 26 Nov '07

26 Nov '07

Hello list, This is kind of a silly question, but do you guys remember how to print a duration on a specific unit? What I mean is something like this: 1::second => dur mydur; <<< mydur >>>; //see the output in seconds (or another time unit) rather than samples I remember seeing this in one of the examples, but I cannot find it! Thanks in advance, Juan-Pablo

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easy random numbers
by jakob kaiser 21 Nov '07

21 Nov '07

Hi, I want to write a small script for ear training with Chuck. Therefore Chuck should produce values that seem to be quite random. But it seems like that the standard functions here are too deterministic. I know that a non-deterministic random function would not be possible, but most programming languages provide functions that create at least new numbers every time I start the same code. However, in chuck something like the following always prints the same numbers when I run it: while(true){ 1::second => now; Math.rand2(50, 1000) => int rndNumber; <<<rndNumber>>>;} Is there an easy way to get something more unpredictable? I don't want to go deep into random generator programming. But the function does not really what you would expect of a random generator, does it? Cheers Jakob _________________________________________________________________ Connect to the next generation of MSN Messenger http://imagine-msn.com/messenger/launch80/default.aspx?locale=en-us&source=…

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overlap factor amplify input signal
by Aylon Eduard 21 Nov '07

21 Nov '07

Hi there, In the following code ifft.last() is sometimes larger than 1, but when the input signal has unity gain, it shouldn't be like this. Actually, what happens, I think, is that the amplification is proportional to the overlap factor. So should setting ifft.gain to hopsize/fftsize be the correct way to handle this? thanks eduard SinOsc s => FFT fft => IFFT ifft => dac; //blackhole; 1024 => int fftsize => fft.size; fftsize/4 => int hopsize; fftsize/2 => int specsize; Windowing.blackmanHarris(fftsize) => fft.window => ifft.window; complex spec[ specsize ]; fun void transform() { fft.upchuck(); fft.spectrum( spec ); ifft.transform( spec ); hopsize::samp => now; } while( true ) { if( Std.fabs(ifft.last() > 1) ) <<< ifft.last() >>>; transform(); }

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Reply to Kassen on shreds, functions and objects
by Jim Hinds 16 Nov '07

16 Nov '07

Apologies: I broke mailing list rule #1: "dont use subject lines like Re: chuck-users Digest, Vol 28, Issue 23" My bad. HI. The function is a function. It is only a function and things within it (the string beep) are totally invisible to anything outside of the function definition. (That's only partly true as they theoretically could be passed by reference to something else, just ignore this fact for now.) 'beep' does not belong to the sporked object. In fact, the name 'tester' isn't likely to be known to the sporked object. Chucks object and class capabilities are growing, but as they say on the street, they are not all 'that.' It has to do with inheritance, namespaces, run-time magic, and lots of stuff that would kill the real- time capability of a shred. All these are fun problems for a computer science person, but not so very fun if you just want to make chuck sing. I usually just pretend that sporked things are not objects at all. A shred is more like an independent agent: a baby. All it knows is the function that is used to give it birth. That function must know how to do all the communication to and from the outside environment. That function can call other functions (in other classes, possibly), look at global variables (in the same source file) and such. I'm sticking with global variables, at least for the short term. Programs in chuck are usually on the smallish side and a few global variables won't hurt the music and are just a necessary evil. I give those global variables useful names like "second_violin_bow_velocity" or some such and to keep track of them better. Jim Hinds http://www.jahbini.org/ > > > On Nov 15, 2007 4:46 PM, Kassen <signal.automatique(a)gmail.com > wrote: > Dear list, > > Shreds are objects (of type Shred) and functions aren't objects. > This is all good and well but it gets harder when we spork a > function and the function becomes a Shred and hence a Object. > Consider this; > > ------------------------ > fun void tester() > { > "boom" => string beep; > while(1) > { > <<<beep>>>; > second => now; > } > } > > > spork ~ tester() @=> Shred foo; > 5::second => now; > > "clik" => foo.beep; //this doesn't work > > day=> now; > ---------------------------------------- > > It's not so clear to me *why* the offending line doesn't work. Maybe > I'm misunderstanding something or making a syntax error but I think > that what we are seeing here is a loss of namespace that would be > useful and I don't understand why this happens. > > I also tried stuff along these lines; > > ---------------------- > class Bar extends Shred > { > //stuff including variables and a constructor > } > ------------------------------ > > If I do that I can instantiate a "Bar" but all it does is run it's > constructor; I can't manage to spork a Bar or assign a sporked shred > to a Bar. I can also make a array of Bar's but all that gets me is > the constructor running; > > --------------------------- > class Bar extends Shred > { > static int number; > <<<number++>>>; > } > > //print a series of numbers, no shreds in sight > Bar array[5]; > ---------------------------------- > > So, now I'm quite happy I said so many times that there are no > "stupid n00b questions" because now it's my turn to ask exactly what > a "Shred" is because I'm starting to feel like I have no idea. :¬) > > Could somebody please explain to me exactly what's going on here? > > > Yours, > Kas. > > _______________________________________________ > chuck-users mailing list > chuck-users(a)lists.cs.princeton.edu > https://lists.cs.princeton.edu/mailman/listinfo/chuck-users > > >

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