[Etoys] Nepalese support: making progress

[Yoshiki Ohshima]

At Wed, 25 Jun 2008 17:43:40 +0200,
Bert Freudenberg wrote:
> 
> Am 25.06.2008 um 07:48 schrieb Yoshiki Ohshima:
> 
> >  We are making another progress on the text rendering support with
> > Pango.  This time, I'm even comfortable to mention it publicly!
> 
> 
> One reason for the performance degradation is that the Pango rendering  
> methods flush the whole screen. That is, for every little string there  
> is a BitBlt of 1200x900 pixels converting from 32 to 15 bpp. To only  
> flush the affected area, you need to give a rectangle parameter to  
> #finish:.

  Oops.  I thought I did.  Maybe there was a reason somehow it didn't
work (I can't remember).

> Also, for each string/paragraph it actually allocates, draws into, and  
> discards a 1200x900x32 Cairo bitmap surface. I did not measure how  
> expensive that is, but it could be avoided by reusing one Cairo  
> surface for all rendering (the affected region will have to be cleared  
> in between of course).

  Yes, RomePluginCanvas class>drawingCanvasFor: was a little attempt
to reuse the surface but the commented part didn't work.

  Patches are welcome!

-- Yoshiki