On Thu, Feb 12, 2004 at 04:22:19PM -0500, David A. Smith wrote:
> I think I understand what you are saying - click on the object some 
> distance from the center and it starts rotating in the direction, perhaps 
> at a rate proportional to distance from the center? 

No, I think I wasn't clear enough.  The widget I'm describing is still
a virtual trackball.

> I haven't done this, 
> but it should be straightforward. I like the virtual track ball because the 
> original selection point stays under the pointer no matter where it moves 

Yes, me too.

> (unless it goes outside of the sphere radius) 

(what happens then?  Nevermind, I see.  I like the behavior: keep
spinning the object at the same rate as when the mouse left the
sphere)

> and when the cursor returns to its original position, the object is
> back to its original pose. The problem with it, and this would not
> be a problem with what you propose, is that the object drifts in the
> axis around the vector defined by the selected point. It isn't bad,
> but it sometimes requires a reorienting of the object. 

What I propose is a different way of reorienting the object.  Rather
than reorienting it by rotating around an axis perpendicular to the
screen (which causes the last dragged point on the sphere to move),
instead rotate it around the axis defined by the sphere center and
the last dragged point on the sphere.

> Note that I
> don't expect to use this much, much because of this problem, and
> because I think the edit cube described later is far more elegant
> and controllable.

I think my idea might help solve the problem a bit better, but I
wouldn't trust it until I tested it with users.

Joshua

> 
> Regards,
> 
> David
> 
> 
> At 03:12 PM 2/12/2004, you wrote:
> >Hi David,
> >
> >Thanks for the link.  Quick question about your description of Virtus
> >trackball... you described a method of rotating the object around an
> >axis perpendicular to the screen.  What about a similar circular area
> >perpendicular to the axis from the sphere center to the mouse pointer?
> >This would allow the object to be rotated without moving the last
> >point on the sphere selected by the mouse.  Have you tried this?  If
> >so, how well did it work?
> >
> >Joshua
> >
> >
> >
> >On Wed, Feb 11, 2004 at 01:19:32PM -0500, David A. Smith wrote:
> >> So don't give up yet. We are still working hard on this. In the meantime,
> >> here is a link to the paper we presented in Kyoto at C5:
> >>
> >> <http://www.reed.com/tealand/lightsmith/04.01.01%20CroquetUIPaperV3.pdf>
> >> The first half of the paper is a rehash of previous work with a bit more
> >> depth. I think you will find the rest of it worth reading.
> >>
> >> Regards,
> >>
> >> David
>