[GSoC] Integrate LO with GNOME - WR#7

[Pranav Kant]

I followed the approach you mentioned.

But the user experience is poor this way. As I am typing things on the
keyboard the immediate effect is that it places dummy tiles for
fraction of seconds in place of invalidated tiles. The callback gets
called when the actual tile gets rendered, and it replaces the dummy
tile with it.

It was much better initially.

Here[1] is the screencast of what I exactly want to say.

[1] https://pranvk.fedorapeople.org/async.webm

On Thu, Jul 16, 2015 at 1:18 AM, Michael Meeks
<michael.meeks at collabora.com> wrote:
> Hi Pranav,
>
> On Wed, 2015-07-15 at 23:48 +0530, Pranav Kant wrote:
>> One important function that I am still not able to call in separate
>> thread is drawing the tiles on the screen. The gtk passes the cairo
>> contexts whenever 'draw' signal is emitted. The drawing works fine if
>> I use this cairo contexts in a synchronous way,
>
>         Ho hum =) this is not possible. The Cairo context is (by design) only
> live for the scope of the 'draw' signal - this is a feature heavily tied
> to double buffering, and the gtk+ rendering infrastructure and it is a
> 'good thing' (TM) =)
>
>         I would recommend instead rendering the tile content asynchronously,
> and if we have no tile rendering something else ;-) ( a scaled version
> of what was there, or a white background).
>
>         LibreOffice can render its tiles asynchronously rather nicely - and
> when they show up - just call the gtk+ equivalent of invalidate:
> gtk_widget_queue_draw_area() and in a few microseconds you should get
> the callback with the cairo context that you want =)
>
>         Hope that helps ! =)
>
>         ATB,
>
>                 Michael.
>
> --
>  michael.meeks at collabora.com  <><, Pseudo Engineer, itinerant idiot
>



-- 
Regards,
Pranav Kant
http://pranavk.me