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

Helge Hafting helge.hafting at
Wed Feb 25 12:43:59 CET 2009

Joel Newkirk wrote:
> On Tue, 24 Feb 2009 12:32:09 +0100
> Helge Hafting <helge.hafting at> wrote:
>> Yorick Moko wrote:
>>>> I (and surely others) am working on a leaner, faster theme - any
>>>> eye-candy that distinctly impacts the user experience should NOT be
>>>> default, and in this case we desperately need a simple and fast
>>>> theme as the default or the immediate impression users will get
>>>> is: "Damn, this is slow!"
>>> nice to hear that
>>> ugly and fast beats pretty and damn slow any day for me
>>> (pretty and fast would also be acceptable ;-))
>> Pretty and fast should be possible then.
>> There is no need for multiple layers of transparent icons. They can
>> be collapsed into one layer with a single transparent icon, looking 
>> _exactly_ the same.
>> Effects when a icon is actually selected is another story, but that
>> sort of thing should not need to impact scrolling.
>> Helge Hafting
> Therein lies the problem, in a sense.  (or a large part of it)
> With the default.edj theme (Illume doesn't override it for Fileman,
> which includes Illume icons) every icon on the 'desktop' initially
> displays just the icon image, be it png, jpg, animated edj, whatever.
> When you touch the screen to scroll it, it will highlight the touched
> icon even if you don't actually select it.
Hm - it shoudln't highlight unless it actually is selected. :-/
>  When it highlights it, it
> makes visible a 'background' png behind the icon, and two or three
> layers of transparent pngs on top of the icon, to give the 'glass
> button with an icon embedded in it' effect. Even when not visible (IE,
> on at least all but one icon at a time) those extra pngs are there,
> their positions are calculated AFAIK and their bitmaps are loaded.

I'm not sure if I understand that. Only one icon looks like a glass 
button - sure. Now, I understand that illume may have precomputed the 
glass button look for every icon there is, spending some memory. But why 
should that need any cpu when scrolling? The glass button effect isn't 
applied to the other icons, so those glass images should just sit in 
memory somewhere untouched?

> (again, AFAIK - those two are internals of Enlightenment and I'm
> guessing)  
> But to make the user experience worse, whenever those extra pngs are
> made visible or invisible, it uses an animated fade-in/fade-out.  So
> every time you drag to scroll, it's busy animating a fade-out on the
> previously highlighted icon, animating a fade-in on the one under your
> finger, and scrolling all the transparent and invisible PNGs.  The
> effect is quite attractive, if only the FR had the horsepower to manage
> it while running a phone, GPS, and frameworkd. :(

I see no fade effect. When I click an icon, it gets the "glass" effect. 
It appear with a slight delay, but there is no visible "fade in". One 
minute there is just the icon, the next moment it is "glassed".
So if much work goes into this - then it is all wasted.

> With the present state of my altered Illume theme (serenity.edj) I've
> trimmed the icons down to just the 'icon' image itself and a single png
> that appears behind it when highlighted.  Outside the theme itself I've
> disabled dropshadows and changed rendering, and disabled the battery
> applet display (pending debugging - it sucks CPU apparently) and it
> reduced Enlightenment cpu usage dramatically.  
> But I found significant further savings by tweaking icons.  
I am looking forward to see all this.  :-) It should definitely improve 
the user experience.

Helge Hafting

More information about the community mailing list