Review Request: an overlay effect element for framesvg

[Marco Martin]

On Tuesday 13 January 2009, Aaron J. Seigo wrote:
> On Tuesday 13 January 2009, Marco Martin wrote:
> > On Tuesday 13 January 2009, Marco Martin wrote:
> > > On Monday 12 January 2009, Aaron J. Seigo wrote:
> > > > On Monday 12 January 2009, Marco Martin wrote:
> > > > > if the possible positions are not that much (lets say something
> > > > > like on the 4 corners) maybe using a single pixmap for caching
> > > > > would still be possible? or maybe just if the position is
> > > > > consistent across instances the impact on cache would still be
> > > > > acceptable hmm
> > > >
> > > > as long as this is cool with Pinheiro and his artistic vision, a
> > > > limited # of positions us the best way to go imho. whether that's 4,
> > > > 6 or 10 probably doesn't matter too much.
> > > >
> > > > once its in, we can play with tweaking the parameters around.
> > > >
> > > > > for the randomness: i would say still indicize in the cache for the
> > > > > applet name but attach it to random numbers that controls the
> > > > > actual positioning. the correspondence saved in a config file? like
> > > > > the one for element rects?
> > > >
> > > > another approach is to use a single initially random seed and then
> > > > just use that always. a random sequence is predictable if you know
> > > > the first seed ;) or use that and a combination of the applet id and
> > > > re-seed the generator each time. then we have only two variables max
> > > > per widget, one of which is shared amongst all the widgets, so really
> > > > only N+1 variables in total with the N variables already known to us
> > > > via applet->id(). by reseeding with an initially random number + the
> > > > id we get a constant set of "random" settings even when widgets are
> > > > deleted.
> > >
> > > hmm, what about simply use applet id as seed and take first 2 sequence
> > > number for the position?
> > > would be quite deterministic and prevedible (given an id always the
> > > same result) but i don't think it would be a problem and could keep
> > > things quite simple
> > >
> > > i'm also experimenting in saving the position on applet config, quite
> > > done also tthat patch(a bit bigger, changes also in applet.cpp) it
> > > would have a bit more entropy
> >
> > and the latter approach is attached :D
> > (made applet friend of framesvg to avoid a pretty useless new api call)
>
> cool; and with this approach and a small number of possible positions, we
> can then tackle:
>
> //FIXME: composing with overlay each time makes it way slower, also caching
> another image isn't sooo good...
>
> huzzah for banging our (your? ;) heads against the wall until we get it
> "right".
>
> nice work ...
yee, has been fun :)
ok, in the last iteration on review board is back to cache everything in a 
single run
and possible positions should be 16 (like a 4x4 grid, maybe could make it 3x3, 
so would be lighter)

Cheers,
Marco Martin