[chuck-dev] ugen design question

[Ge Wang]

Hi Brad!

> However, ideally I'd like the function to deliver/update the incoming
> value whenever it came from max/msp, something like this:
>
> (i.e. no loop in the script, but during execution any change coming 
> from
> maxin.inletval would indeed affect the sineosc frequency).

If I understand this correctly, then you might make maxinlet a chuckian 
Event (as Perry pointed out like the OSC-related objects, as well as 
MIDI, HID, and a few other objects in ChucK).  In that case, you can 
write code that looks like:

     // infinite event loop
     while( true )
     {
         // wait on event
         inlet => now;

         // set freq
         inlet.inletval => s.freq;
     }

This would only fire as updates came in from the inlet object.  It 
should work, but the code ain't pretty.  Look in chuck_lang.* and 
midiio_rtmidi.* for MidiIn related-stuff.  I think the crucial 
components are:

1. the class 'maxinlet' should extend "Event" in the 
type_engine_import_class_begin
2. the actual C++ class that does the work should extend Chuck_Event, 
or at least hold a pointer to a Chuck_Event to be notified on event
3. the actual C++ class may want to have a circular buffer of some kind 
for incoming events
4. as events come in, they get put on the buffer, and 
.queue_broadcast() should be called on the Chuck_Event to be notified - 
the rest is handled by chuck
5. the chuckian class 'maxinlet' should also implement the can_wait() 
function.

Wow, yuck - what a disaster.  Needless to say, we hope to improve this 
for the upcoming import mechanism...

Best,
Ge!