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pulse width modulation
by Michael Heuer 08 Feb '10

08 Feb '10

I'm trying to model the following in ChucK "OSC1, OSC2, and an LFO (Low Frequency Oscillator) Modulation: OSC1 produces a simple square wave tone, the pulsewidth of which is modulated with OSC2, and then amplitude modulated with the LFO oscillator." I think I understand the LFO amplitude modulation part, but I don't understand what pulse width modulation with osc2 means. SqrOsc osc1; SqrOsc osc2; SqrOsc lfo; Gain master; lfo => blackhole; osc1 => master; 220.0 => osc1.freq; 0.8 => osc1.gain; 20.0 => lfo.freq; 0.9 => lfo.gain; fun void updateAtSampleRate() { while (true) { ((lfo.last() + 1.0) / 2.0) * 0.8 => osc1.gain; 1::samp => now; } } master => dac; spork ~ updateAtSampleRate(); 2::second => now;

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Mind control
by Hans Aberg 07 Feb '10

07 Feb '10

CNN had a story about this. A bit pricey, but an interesting interface: http://www.neurosky.com/ http://www.neurosky.com/mindset/devtools.html http://developer.neurosky.com/ Hans

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incorrect compiler error
by Michael Heuer 03 Feb '10

03 Feb '10

The following appears to be a bug in the compiler Foo.ck: public class Foo { Baz baz; fun Bar bar() { return baz; } } class Bar { } class Baz extends Bar { } [Foo.ck]:line(7): function 'bar@0@Foo' was defined with return type 'Bar' -- but returning type 'Baz' [Foo.ck]: ...in function 'bar' Changing the definition order solves the problem class Bar { } class Baz extends Bar { } public class Foo { Baz baz; fun Bar bar() { return baz; } } michael

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AutoCorr and XCorr UAnae
by Andreas Apergis 03 Feb '10

03 Feb '10

Hi list,does anyone happen to know the behaviour of AutoCorr and XCorr UAnae?They've been added in 1.2.1.2 but there is no documentation or example of them.An LPC UAna seemsto be defined in the source but I cannot even instantiate an object of such type.Any help ?Thanks, Andreas

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sfonts?
by David Loberg Code 01 Feb '10

01 Feb '10

How do I read and play soundfonts in ChucK? (Or is that still on a wish list?). david David Loberg Code School of Music Western Michigan University Kalamazoo, MI 49008 code(a)wmich.edu

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Difference between .freq and .sfreq
by Sean Sawyer 26 Jan '10

26 Jan '10

Probably a noob question, but I'm not sure of the difference between these two parameters. I see from the documentation that one is "phase-matched" and the other is not, but after messing around a bit I've been unable to come up with a scenario in which behaviour differs when using one or the other. Can anyone shed some light on the difference? Cheers, Sean

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a koan (and a bug request)
by Robert Poor 25 Jan '10

25 Jan '10

Quiz: what will happen when the following code is run[*]? ================= class Trait { fun void announce() { <<< "I am generic." >>>; } fun void invoke() { announce(); } } class Legacy extends Trait { fun void announce() { <<< "I am legacy." >>>; } } class Lunacy extends Trait { public void announce() { <<< "I am lunacy." >>>; } } (new Legacy).invoke(); (new Lunacy).invoke(); ================= If you predict that it prints: "I am legacy." : (string) "I am lunacy." : (string) then here's a hint: there's a typo in the definition of Lunacy's announce() method where it says "public void announce()..." instead of "fun void announce()...". If you predict that it gets a compiler error when it encounters the typo, well, you'd be wrong there as well. What happens instead is that it compiles without any error messages, and the result is: "I am legacy." : (string) "I am generic." : (string) It took me a LONG time to find this one (and an even longer time to boil it down to a succinct example). Will the powers that be please take this as a request to beef up the parser? Thanks. - Rob [*] in particular, chuck v 1.2.1.3 mac os x : intel. I'm guessing that this is platform independent, though...

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accessing static methods through an instance?
by Robert Poor 24 Jan '10

24 Jan '10

[Coincidentally, Stefan's message about identically named (instance) methods arrived as I was composing this note. It's possible this is the same thing, but with a different twist...] One might expect that an instance reference calls an instance method and a class reference calls a static method even if they have the same name, but it ain't so. And the compiler doesn't issue any warning. Consider the following: ==== file: fn.ck public class F { fun static void method() { <<< "static method()" >>>; } fun void method() { <<< "instance method()" >>>; } } F.method(); // call method via class (new F).method(); // call method via instance ==== produces: "static method()" : (string) "static method()" : (string) ==== I can convince myself that this isn't really a bug, if "static" really means "make this variable or method shared by all instances", but it would be nice if the compiler warned you about identically named methods. (Note that the compiler DOES issue an error for identically named variables.) - Rob

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Identical functions
by Stefan Blixt 24 Jan '10

24 Jan '10

You can declare identical functions, with the first one apparently taking charge: fun void g(int i) { <<< "fddf" >>>; } fun void g(int i) { <<< "fdfd" >>>; } g(3); I have a feeling this is old news, but I can't recall this specific issue being mentioned. It doesn't feel right. It's the same if the functions are inside classes. Could it have something to do with enabling cross-shred referencing? Cheers, Stefan -- Release me, insect, or I will destroy the Cosmos!

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got .deb?
by mike clemow 24 Jan '10

24 Jan '10

Hello Fellow Chuckists, Is anyone maintaining a .deb package for chuck/mini? Best, Mike -- http://michaelclemow.com http://semiotech.org

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