Re: GtkTreeView unbearably slow

[Vikram Noel Ambrose <noel ambrose gmail com>]

David Nečas wrote:
> On Sun, Dec 27, 2009 at 11:23:46PM +0000, Andy Spencer wrote:
>   
> > > Here is a sample program that reflects the issues I'm having:
> > > http://en.pastebin.ca/1728846
> > >       
> > I tried trimming down your example to see if I could find anything that
> > might have been causing problems, but no luck. Here's the trimmed down
> > version I came up with:
> >
> >   http://vpaste.net/0si1W?s
> >     
>
> And you actually observe several seconds long lags during scrolling with
> this sample program?
>
> Well, I am not able to reproduce it -- on a notebook.  The scolling
> indeed lags behind a bit which is observable especially if I maximize
> the window, but that's all.
>
> I wonder what causes the difference.
>
> Yeti
>
>
>   
Thanks Andy for that version. Its a different program (Styling, 
Callbacks etc...) but nonetheless, functionally similar. And it runs 
MUCH faster than my version.

I went through my code commenting/uncommenting pieces until I got it as 
fast as Andy's version. There were many small things that gave me a few 
percent speed increase, but the big boost came from the absence of 
"gtk_tree_view_set_grid_lines". With this setting included, like I said 
earlier, I get several seconds delay between the mouse scroll wheel and 
the GtkTreeView, however with this setting removed, the delay is only a 
few milliseconds.

I tried various combinations of styling settings and can confirm that on 
my machine the absence of _grid_lines translates to a 10x speed increase 
in scrolling responsiveness on GtkTreeView.

Having said that, its still no way near as fast as QTreeView. But at 
least now someone who knows the GTK+ internals can look into 
_grid_lines. and narrow down the problem.

Thanks guys.


Vik.