Re: [Usability]Re: All animations should be disableable

[Kent Lyons <kent cc gatech edu>]

On Fri, Oct 18, 2002 at 12:19:41PM +0100, Calum Benson wrote:
> On Thu, 2002-10-17 at 23:23, MArk Finlay wrote:
> 
> > Well i was talking about both - but in a bigger picture kinda way i
> > think it should be policy or in the HIG or something to have all
> > animations optional.
> 
> It's in the accessibility guide
> (http://developer.gnome.org/projects/gap/guide/gad/):
> 
> Animation
> 
> Used sparingly, animation can be useful for drawing attention to
> important information in your application-- and it can look cool, too.
> However, it can be problematic for some users, so make sure they can
> turn it off.
> 
>     * Don't use flashing or blinking elements having a frequency greater
> than 2 Hz and lower than 55 Hz. This includes text as well as any
> graphical objects. Anything in this frequency range may cause particular
> problems for users susceptible to visually-induced seizures. Note that
> there is no "safe" frequency, though. If flashing is essential, you
> should use the system's cursor blink frequency (which should itself be
> customisable), or allow users to configure the frequency themselves.
> 
>     * Don't flash or blink large areas of the screen. Small areas are
> less likely to trigger seizures in those susceptible to them.
> 
>     * Make all animations optional. The animated information should be
> available in at least one non-animated format, at the user's request.
> 
> For some reason we seem to have missed out these guidelines in the HIG,
> though, although it did make it into the checklist at the back:
> http://developer.gnome.org/projects/gup/hig/draft_hig/reality-checks.html#id2857245
> 
> I have to admit it's not immediately clear to me whether these
> guidelines applies to animations such as the metacity 'minimize'
> animation, or just to continuous or non-redundant animations.  I guess
> it should probably be both, though.
> 

Although it is probably good to minimize the type of animations
outlined above, animations in general can servr a very useful purpose
in UIs. Here is a good overview paper on animations in UIs: 

Bay-Wei Chang, David Ungar, Animation: from cartoons to the user
interface, Proceedings of the sixth annual ACM symposium on User
interface software and technology, p.45-55, December 1993. 
http://www.cc.gatech.edu/classes/AY2002/cs4470_fall/p45-chang.pdf


Here is a good quote from the intro:

"When the user cannot visually track the changes occurring in the
interface, the causal connection between the old state of the screen
and the new state of the screen is not immediately clear. How are the
objects now on the screen related to the ones which were there a
moment ago? Are they the same objects, or have they been replaced by
different objects? What changes are directly related to the user's
actions, and which are incidental? To be able to efficiently and
reliably interpret what has happened when the screen changes state,
the user must be prepared with an expectation of what the screen will
look like after the action. In the case of most interactions in
unanimated interfaces, this expectation can only come by experience,
little in the interface or the action gives the user a clue about what
will happen, what is happening, or what just happened."


Kent

-- 

Kent Lyons
kent cc gatech edu
Georgia Institute of Technology