SImple SYnthetiser
------------------

FEATURES:
 - real time midi synthetiser
 - polyphonic management
 - virgule fixe processing



EXEMPLE:

This is an exemple of instrument description. It will change soon.

======BEGINING OF THE INSTRUMENT DESCRIPTION======
instru carre {
	data {
	        value polyphony_nb_voices=2;
	}
	voice {
		data {
			new buffer tmp;
		}
		square(T:midi_note_period, buff:tmp, level:midi_velo);
		envolope(buff:tmp, duration:midi_note_duration);
	}
}
======END OF THE INSTRUMENT DESCRIPTION======

In the future, there will have event handling and procedures:
======BEGINING OF THE INSTRUMENT DESCRIPTION======
module carre
{
	process
	{
		data
		{
			in value param1=42;//with range(0,42);
			in fixed freq(min:42, max:21000, default:42, precision:4);
			out buffer output;
		}
		square(T:freq, buff:pouet);
	}
}

instru pouet
{
	data
	{
		in value voices_nb=42;
		out buffer audio_output;
	}
	process voice=carre(value paramX:...);	#creation, initialisation et affectation
	process global				#creation, definition, affectation
	{
		data
		{
			value tmp;
			in value volume=42;
		}
		event voice
		{
			data
			{
				in value note;
				in value velocity;
				in value cord;
			}
			note2freq(note:note, freq:freq);
			sound_bank_load(position:cord, output:sound);
			create_voice(freq:freq);
		}
		process_voices(mixer:log, param1:42, output:audio_output);
	}
}

======END OF THE INSTRUMENT DESCRIPTION======
Object will be needed to be able to change their states.

creation de voix
reception d'events
events routés par voix

Systeme|Instrument|Note


...

Wave forms: Sin, Square, Noise, Table(Base64), Whatever...
Enveloppe: ADSR, Whatever...
Filters: Low, High, Whatever...
Mixer: Whatever...

PIANO:WaForms+Env
CHROM_PERCUSSION:WaForms+Env
ORGAN:WaForms+Env+Mixer
GUITAR:WaForms+Env+Reverb
BASS:WaForms+Env
STRINGS:WaForms+Env
ENSEMBLE:WaForms+Env
BRASS:WaForms+Env
REED:WaForms+Env
PIPE:WaForms+Env
SYNTH_LEAD:WaForms+Env
SYNTH_PAD
SYNTH_EFFECTS
ETHNIC:?
PERCUSSIVE:Samples?:Noise
SOUND_EFFECTS:Samples

Integration to gstreamer ? What's that ?

...

View_sound: add spectrum.

INTERNALS:

INIT:
sisy load a file in a midi pipe or open a port.
for each chan, an instru is loaded, sisy.conf is parsed.
instru are build, voices are copied as affects and watches.
IO data are cloned.

PROCESS
sisy read on the port and dispatch the midi mesages on chans.
the chans fill the the instru, voices and midi IOs banks.
modules are processed, affects are done and callback are called.
mixing
audio_writing


que ca soit un piano, un orgue ou une guitare qui est syth'etis'e, on
a des ressources limit'ees qui sont les cordes (6 ou 88), les tubes
(un ou plein).

 - La polyphonie dans ce cas consiste a activer ou non ces resources. -

Si on se trouve dans le cas ou l'on a plus de contraintes fixes, on
peux creer les resources suivant les besoins.

 - La polyphonie dans ce cas consiste a r'epliquer les ressources autant
de fois que necessaire. -




Maintenant, on recois des notes a jouer avec une certaine velocit'ee,
et eventuellement certains parametres.

Quand on recois une note, dans le ca dur, ou utilise les ressources
dispo ou sinon, on cree les resources.



Schema audio et controles