[Lazarus] Cairo library usage

Mattias Gaertner nc-gaertnma at netcologne.de
Sat May 17 16:11:38 CEST 2008


On Sat, 17 May 2008 08:45:39 -0300
Luiz Americo Pereira Camara <luizmed at oi.com.br> wrote:

> Felipe Monteiro de Carvalho wrote:
> > On Fri, May 16, 2008 at 5:48 AM, Graeme Geldenhuys
> > <graemeg.lists at gmail.com> wrote:
> >   
> >> * What is your feeling about the library?
> >>     
> >
> > It was found that cairo is the reason why lcl-gtk2 is so slow, and
> > therefore, I don't like it very much =)
> >   
> 
> Some facts:
>  - LCL-gtk2 applications are slower than gtk2 pure applications

What did you measure? How much? 


>  - LCL does not use cairo directly to draw, it uses gdk
>  - Gdk is faster than cairo
>  - Gtk2 internally still uses gdk in most places
> 
> So assuming cairo is used a lot by gtk2 this could explain why Gtk2
> is slower than Gtk1 but not that LCL-Gtk2 is slower than Gtk2.
> 
> Things to look when optimizing LCL-Gtk2:
> 
>  - Pango (FontConfig is called a lot in LCL-Gtk2 applications)

How do you know?

>  - Double buffer is disabled

What controls?

 
> If the LCL devels agree in one week i can provide a complete
> separated Gtk2 interface so the changes to get LCL-Gtk2 faster can be
> done easily and without breaking gtk1

What do you mean with 'complete separated Gtk2 interface'?


Mattias



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