Re: fdo#47907: fix flickering scrolling in Basic IDE

Hi János,

On 31/07/12 12:34, János Uray wrote:
> Again? Oh, yes.
> Now here it is.
>
> On Tue, Jul 31, 2012 at 11:10 AM, Noel Power <nopower@suse.com 
> <mailto:nopower@suse.com>> wrote:
>
>     Hi János
>     you forgot to attach the patch :-)
>
>     On 30/07/12 19:04, János Uray wrote:
> >     This patch solves this bug:
> >     https://bugs.freedesktop.org/show_bug.cgi?id=47907
> >
> >     The text was flickering because Window::Invalidate() clears the
> >     client area by default. To prevent this, I've added an
> >     INVALIDATE_NOERASE parameter to Invalidate() calls.
> >     On the other hand, the background still needed to be erased
> >     outside the text: the indentation space and the rest of the line.
seems to work better :-), imho still is not as smooth as 3.4, I would 
love to know *why* we get this behaviour now in >=3.5, is something 
triggering Resize() more often now ( and why indeed is Resize even 
called when scrolling ). Additionally I am a but nervous about changes 
to the TextEngine  ( a piece of code I have no familiarity with at all 
). Saying that the change you made seems quite small ( despite the 
confusing diff due to the whitespace changes ) I suppose it is the last 
part of the patch that is really necessary. But still it just feels 
wrong that we need to tweak the TextEngine and I wonder are we 
correcting a side affect rather than fixing the root cause ( but of 
course your change might even be valid regardless of the IDE 
(mis)behaviour or maybe even entirely correct for the IDE problem, I 
confess I haven't got a clue ). I cc Kohei here too who having looked at 
the editeng recently might ( but maybe not ) have some opinion.

Noel