[iiwusynth-devel] Re: Wish list: Modulators

[Josh Green]

On Sun, 2002-04-14 at 02:29, M. Nentwig wrote: 
> Hello,
> 
> Two minor issues with the current version:
> - The default value for 'volume' is 8192. Choosing 'Reverb' and then
> 'Volume' sets it correctly to 100.

Yeah, my only excuse is being lazy for that one. The controller is
actually the pitch controller, only the option menu displays volume. So
the default option menu value needs to be changed. Will fix. 

> - When I change from the 'Piano' view to the 'velocity view' using the
> icons, the keyboard display changes correctly. But the contents of the
> window below are not updated (selecting another item helps).
> 

Checked it, did not know.. Must fix :)

> Then, an item for the 'wish list'.
> In iiwusynth, I have now implemented the General-MIDI default modulators
> to-the-letter according to the specs (excluding typos :-)  , more about
> that on the iiwu list. So in the near future, iiwusynth should be able
> to deal with arbitrary modulators from the soundfont.
> Then it will be useful to have a sort of 'modulator editor', which
> allows to create, edit, delete an arbitrary number of modulators.
> 

Awesome! Nice to hear.
Generators are also on my wish list, so this works out good :) I'll give
the modulator section in the sound font spec a good reading again to
decide how I want to tackle the user interface for it. I want to get
sound font saving and item pasting working first. Sample importing is
now working again (not checked into CVS yet). Would be nice to get it to
the point of being able to actually create a sound font before adding
modulator support. This will probably only take a week or two though.

> If I were to implement a UI it would look somehow like this:
> - a listbox that lists a summary of all existing modulators in the
> current preset or instrument zone (I think there are only two places,
> where modulators can occur in the sound font, PMOD and IMOD)

Yep..

> - Buttons 'Create new modulator' and 'Delete this modulator'
> - A source selection dropdown, that lists all possible sources (key
> number, velocity, aftertouch, valid MIDI controllers etc)
> - A destination selection dropdown, that lists all synthesis parameters
> with real-time modulation capability (pitch, initial attenuation,...)
> - A type selection (concave, convex)
> - A polarity switch
> - A type switch (unipolar, bipolar)
> - An amount field
> 

I started a GUI element in glade a long time ago that provides most of
these controls. The code was never created behind it though, since there
isn't currently a synth that supports this in Linux. Its really really
cool that iiwusynth is going to and that its not that far away!

> Since the 'General Midi default modulators' are now in place, they have
> to be explicitly overwritten by the sound font to get rid of them.
> For example: A synth / organ sound uses the same volume for any
> velocity. One way to implement this is to overwrite the
> vel-to-attenuation and vel-to-filter default modulators with an amount
> of 0.
> For this, it would be useful to have checkbuttons 'default GM vel->att',
> 'default GM vel->filter', etc.
> Those are turned on by default, and turning them off inserts a modulator
> with the desired effect.
> If the user has created a modulator that will cancel any default GM
> modulator, the box is greyed out. This is the case, when one existing
> modulator has the right source, destination and type, but the amount is
> not 0.
> But this is just an idea.
> 

Default values for generators need to be handled in Swami better
(actually its not really even currently handled). Probably will just put
a toggle button next to each generator control that will be active if
the value is not set (default). Clicking this button would explicitly
set it to its default value.
For modulators though, I don't think I really like the idea of having
toggle buttons for all the default modulators. I think I would just have
them listed in the modulator list like any other control but there
should definitely be an indicator that lets the user know that it is
just a default modulator (unfortunately changing colors for different
widgets in GTK is kind of messy due to themes, so a check or something).
Anyways. I'll probably get some better ideas once I read up on the spec
again a few times.

> Cheers
> 
> Markus

Cheers!
        Josh Green