[linux-audio-dev] Re: Programming Synth Knobs?

[Loki Davison]

On 2/12/06, peter <zenadsl6252 at zen.co.uk> wrote:
> On Sat, 2006-02-11 at 02:29 +0100, krampenschiesser at freenet.de wrote:
> > Does anyone know a good way to write code that renders synth
> knobs/potis/controllers?
> > I was looking around to rotate an image which only worked in opengl...
>
> Assuming for a moment that you don't have strict memory requirements,
> you might want to consider loading an animation and swapping the frames
> when the controller is moved. There are a few implementations in qt and
> gtk that use this method and i've created some animations in blender
> (http://www.blender.org/cms/Home.2.0.html) for one based on this
> widget (from galan):
> http://cvs.sourceforge.net/viewcvs.py/galan/galan/src/gtkknob.c?rev=1.8&view=markup
>
> The benefits:
>
> easy eye candy (pretty and complex prerendered knobs) with little or no
> custom drawing code (depends on the toolkit your using)
> easy to change the appearence by changing the animation
> fairly easy on the cpu
>
> The downsides:
>
> static images == a finite step resolution
> memory usage (probably >100K at least for a smoothly animated knob)
> learning to use or finding someone to use a 3d modeller or animation
> tool.
>
> For example, this shot shows a work in progress interface for a DSSI
> synth plugin. I rendered the knobs in blender with an alpha channel to
> get translucent shadows. The widget uses generic gtk functions to
> render each frame over the background as the knob is turned.
> It looks pretty nice in action, even if it's an eye candy overdose
> for some tastes.
> (if you dispense with the alpha and transparency, it's naturally faster)
> http://www.zenadsl6252.zen.co.uk/purgatory.png
>
>
> If you're holding out for an algorithmic solution of some kind..
> ..i just wasted your time ;)
>
> Cheers,
> Pete.
>
> --
>
> ======================
> paugh on irc.freenode.org in #sweep, #lad
> kickback at users.sourceforge.net
> ======================

Please, pretty please get rid of the keyboard. If you want a sexy
keyboard, skin vkeybd don't include a keyboard in your dssi. Apart
from that i actually quite like it.

Loki