GUI responsiveness (was Re: SHR first impression : it's slow ?)

[Helge Hafting]

Joel Newkirk wrote:
> On Wed, 25 Feb 2009 12:43:59 +0100
> Helge Hafting <helge.hafting at hist.no> wrote:
> 
>> Joel Newkirk wrote:
> 
[...]
> As I said, I'm guessing, but when I removed the extra PNG images and
> leav just one, enlightenment average CPU drops and the display is more
> responsive. The glass button effect /is/ applied to every icon,
> it's just that the parts ('parts' in edc syntax) relevant to the effect
> are flagged as non-visible by default.  I'm assuming that even when a

Urrgh - such inefficient coding. Making a 'movie' per icon - every time 
- and just not showing it for most of them. :-( The sane way is to only 
do the _needed_ calculations. Either animate a single icon when the 
effect is actually used, or generate all the frames once and just store 
them till needed. I wonder how they come up with such stuff. This is not 
only a problem on weak processors - it wastes energy on the good ones as 
well. :-(

Maybe we ought to use a modified duke nukem as an app launcher interface 
instead of enlightenment. Duke has a _better_ framerate for scrolling 
and zooming - in 3D!

Shoot at icons to start apps. Fire at the process list to kill. kill -9 
using a bigger gun.  ;-)


[...]
>   Wonderful feature
> to have, but I suspect that the calculations involved in this scaling
> and other nice effects E offers are at least a slight detriment to the
> (integer) FR user experience...
>
I wish people though more about efficiency. One can have all sorts of
wonderful effects by precomouting some stuff _once_, and then use plain 
bit block transfers. 1990 game machines was weaker than the FR, but that 
did not seem to be a problem then.

[...]
> If you watch an icon closely when you press your stylus against it, you
> can usually perceive the fade-in taking place, particularly if your FR
> is straining, in which case you can sometimes see a few distinct delayed
> steps.  The linear transition is set to occur in 0.2 seconds fading in,
> and 0.1 seconds fading out - so it is quite brief.  I believe it
> abides by the "Framerate" setting in Illume config (the spanner), such
> that a 30fps setting and a 0.2 second fade equal a 6-frame animation.

I have now set the framerate to its minimum of 5, and turned off
animations where I could. At least the keyboard appears more quickly now.

Icon animation and only two icons - selected and
unselected.

> Thanks for the encouragement. :)  It's already improved my user
> experience, but in my poking about I've broken things as well, which is
> why I'm not offering the .edj to anyone yet.  I plan to start from a
> clean extraction from illume.edj and default.edj once more, applying
> only the changes confirmed to be beneficial and not cause E to segfault.

Great!
I hope this will go into the distributions, at least as a selectable 
alternative. Eye candy is nice - but only as long as it doesn't create 
performance problems.

Scrolling is slow enough even if I grab the iconless corner - so that no 
icon actually change state. (None was selected, none became selected) 
But of course it is still slow if all those icons have to be scaled 9 
times or so before drawing the screen.

> But at the pace I'm going that'll be a couple weeks still.  Hopefully
> at that point I'll be able to offer tarball and ipk versions of the
> theme for both enlightenment in general and for elementary (shr-dialer
> and kin, paroli, Raster's alarm, shr-config, etc all use elementary) as

Take your time. Ideally, a beta release whenever one more performance 
killer is chopped off. If it isn't too much extra work.
[...]
> /*
> below are lines 14053 through 14438 of 'default.edc', inside
> 'default.edj', this copy extracted from FSO M5 IIRC but I believe the
> same utilized in SHR. At the top it specifies what images are required
> for this 'group', which defines a single icon on the desktop. (Illume in
> our case) It also uses 'pager_base2.png' which is defined in a global
> images stanza.  
> */

Scary stuff. An interpreted language just for the icon set.

When I try to impress people with the FR, I show them cool apps like 
linball. Not the icon interface. It is not that hot anyway - and 
slowness is simply bad.

Helge Hafting