From: owner-3dui@hitl.washington.edu on behalf of Jan Flasar
[flasar@informatics.muni.cz]
Sent: Thursday, January 27, 2000 8:57 AM
To: Ernst Kruijff
Cc: 3dui List
Subject: Re: system control - techniques and guidelines

Hi,

I just join to 3dui list.
I occupied with 3D gui interaction in virtual enviroment and so I have some
comments about Question 2 (guidelines from your letter I know). 
In my env. I use 5th Data Glove, Polhemus Ultratrak, CrystalEyes2 and 
use to selection anything from 3D gui index finger (ray of i-finger and 
direct/indirect touch of i-finger), so I don't know if my answer will be 
useful to you. My gui is "floating" in VE.

>---------------- Question 2
>The second question I have applies on guidelines for system control. Due
>to the relative lack of evaluation on 3D system control, it is pretty hard
>to come to guidelines which are really applicable - I have come to the
>next list, which is "extracted" from several studies (including Mine,
>Shaw, Conner, and so on) and several studies we did here with our own
>software environment (largely user observations of over 1000 users over
>the last 5 years).  We use a HMD and a stylus in our environment, by the
>way. 
>
>Still, the guidelines might well -not- apply at the environment you have,
>or the experiences you have.  Comments are very welcome, and so are new
>guidelines which might be added to the list! If you have publications
>which support or undermine (!!!) the guidelines, I would also appreciate
>it a lot to get a link!I have tried to order the guidelines a bit, and
>gave some comments to them. The guidelines are focussed at immersive
>environments, though some desktop-based stuff has found its place in the
>guidelines too.
>
>
>
>
>-------------------- Guidelines
>
>SPEED
>
>-Place system control at the right place
I know that is true, but I thing that menu can be placed at left-down part 
(in our system) too. It's speedy as well (for me). If we want apply to
selection direct touch of finger then menu must be rotated about x and y
axis in direction into scene (5-10 degrees), because every human click
to item in direction down (it's natural) and this cause (when menu isn't
rotate) that the user select item from menu which below selecting item.
Further, menu must be placed near body because if it will be far from body
then evere selection in pretty hard (after little time hand is beginning
pain :)).
Menu haven't to rotate if we apply indirect touch selection.
Then we sharpen item which is near around finger and then confirm with 
some command (push button, make some gesture with the second hand, ...). 
In my opinion, this is faster than direct touch selection (user needn't 
hit the item precisely).

-Use metaphors if menu is hidden
 Somebody can forgot, what he selected. The metaphor can be placed in some
part of screen or on model of hand (in our system).


 
I don't know if my answer will be useful to you but I wrote this letter yet.
And sorry for my english too.


Regards,

-Jan



----------------------------------------------------
Jan Flasar
E-mail: flasar@informatics.muni.cz

HCI lab, (http://www.fi.muni.cz/usr/sochor/HCILAB.html)
Faculty of Computer Science, Masaryk University
Botanicka 68a, 602 00 Brno, Czech Republic