[LAD] "bleeding edge html5" has interesting Audio APIs

David Robillard d at drobilla.net
Tue Nov 22 01:04:04 UTC 2011

On Mon, 2011-11-21 at 23:59 +0000, James Morris wrote:
> On Mon, 21 Nov 2011 18:33:38 -0500
> David Robillard <d at drobilla.net> wrote:
> > On Mon, 2011-11-21 at 22:57 +0000, Fons Adriaensen wrote:
> > > On Mon, Nov 21, 2011 at 11:42:31PM +0100, Nick Copeland wrote:
> > > > 
> > > > > Subject: Re: [LAD] "bleeding edge html5" has interesting Audio
> > > > > APIs From: d at drobilla.net
> > > > >
> > > > >  All we need is a couple of sliders and knobs and such.  It's
> > > > > quite straight forward
> > > > 
> > > > Ah, is that all we need? I never realised it was so simple. Can I
> > > > have them in some dull, boring grey colour with sad square boxes?
> > > > You know, something that really inspires and that will convince
> > > > every iPad user that their ubercool GUI are a total waste of
> > > > time. Can you do that for me? That would be a killer!
> > > 
> > > Even almost every GUI toolkit sliders fails when used for
> > > anything serious in audio. Try tuning your oscillators in
> > > e.g. AMS when the auto-resizing frequency slider happens to 
> > > have 27.142857 steps per octave. 
> > 
> > For stuff like this you need a way to enter precise values with a
> > corresponding text box anyway.
> > 
> > Though the old fan slider idea was a pretty good one...
> Earlier this year I tried updating the PHAT toolkit to use the Cairo
> backend for rendering (because the drawing code used by PHAT to
> render the fans is deprecated).
> The problem I found was that in order to get Cairo to draw the phans
> on the desktop (without obliterating the desktop) desktop compositing
> was required. I went round in circles looking at the documentation
> trying to find a way to get it working without compositing enabled
> (and without using deprecated code) but by the time I got to looking in
> the GTK source itself I decided to make the fans optional while
> additionally allowing shift to be used in combination without dragging
> the slider for greater precision (and ctrl for even more).
> I called it 'phin' and it can be found in the petri-foo source if you
> want to look.

Yeah, I think it was always sort of a given that this would never work
ideally without compositing, unfortunately.  I assume transparent window
hacks don't work out so well?

It's a shame really, it's IMO by far the best controller idea I've seen
- knobs on a mouse-driven computer screen are, have always been, and
will always be, completely inappropriate...

I wonder how useful it would be with the limitation of keeping it
confined to one window would be... with Gtk3, the entire app draws to a
single Cairo context so I believe it should be straightforward to draw a
big fan or whatever across the entire window...

I should probably implement this idea in FlowCanvas for (at least)
Ingen.  It should be doable there, confined to the canvas of course, but
since it's scrollable it should be possible to make that usable by
automatically scrolling as needed (the usual thing with dragging stuff
in a scrollable widget).



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