[LAD] Mouse/knob interaction

[fons at kokkinizita.net]

On Tue, Sep 07, 2010 at 07:20:10PM +0100, Gordon JC Pearce wrote:

> This is going to stir up a bit of discussion!
> 
> Rotary knob GUI elements - should you move the mouse in a circle to
> operate them, or up and down?  What about side to side?

The ones I'm using on some (unpublished ATM) apps and plugins
do:

* click, move either up or right to increment, left or down
  to decrement, or

* use the mouse wheel, With shift pressed you get higher
  resolution.

For some functions they also display a numerical value for
a few seconds when touched.

The important thing with rotary controls is that everything 
should be relative. Having the knob move intantly to a click
position is more than useless, and in some cases quite dangerous.

This is similar to the advantage of *real* rotary controls
vs. linear ones. Try to control a linear fader while you're
running from a riot police assault during a manifestation. 
Or under attack from a US helicopter mistaking your mic for
a rocket launcher.

The nice thing about rotary controls - both real and sofrware
- is that they provide a very good quick visual indication of
the current state, something a spinbox well never do, while
linear controls require much more space.

BTW, the main reason why mixers have linear faders is *space*.
A really big rotary knob provides much better control than any
linear fader. But it doesn't allow a for design with just a few
centimeters per channel strip. So as mixer channel counts went
up, the only solution was a linear fader.

Ciao,

-- 
FA

There are three of them, and Alleline.