[Clam-devel] Re: QSynth Knobs

[Pedro Lopez-Cabanillas]

On 4/17/07, Pau Arumi <parumi at iua.upf.edu> wrote:
> > On Mon, April 16, 2007 23:38, David Garcia Garzon wrote:
> >> Hi, Rui. I liked a lot the knobs you are using for qsynth. The widget
> >> which was adapted (and enhanced?) from Chris Canam Rosegarden code. I
> >> integrated it in CLAM and now is a widget more you can use to prototype
> >> applications. Apart from porting it to Qt4 i also did some enhancements:
> >>
> >
> > Credit should also be due to Pedro Lopez-Cabanillas who brought the
> > original Rosegarden knobs to Qsynth in the first place ;) He's being CCed
> > here too.
>
>
> Really? The world is so small! We met him once here in Barcelona
> like two years ago. Hi Pedro! are you still around Barcelona?

Yes, I'm still here :-) and available to drink a beer, if you want.

> >> * Pixmap cache was removed. Maybe i did something wrong on the port but
> >> the widget was very sludgy until it generated all the possible possitions
> >> and on resizing was worst. Also qt4 does double buffer by itself -> no
> >> need for pixmap at all.

The point with the pixmap cache was to draw only once each position of
a knob, when there are several knob instances in the same application.
It is only worth if all (or many) of them share the same colour and
size. I recall that it was a little speed optimisation, but of course
the situation may have changed in newer Qt versions.

> > those new knob components will be welcome back rightly,
> > specially on Qsynth, of course ;)

Rui: the widget has been ported already to Qt4 by Chris, and included
in Sonic Visualiser.
http://sv1.svn.sourceforge.net/viewvc/sv1/sonic-visualiser/trunk/widgets/AudioDial.cpp

Regards,
Pedro