Re: [Linux-fbdev-users] Question about cfb_copyarea

[Juergen B. <jue...@kr...>]

Hi Petr,

On Wednesday 31 January 2007 10:12, Petr Vandrovec wrote:
> > is this list alive?
>
> More or less.  Less...

Seems so... :-)

> > Currently I'm trying to develop a accelerated framebuffer driver. My own
> > imageblit and fillrect functions are working now. But my copyarea
> > function will never be called. I thought it will be called to scroll the
> > screen. But it seems not. Does anybody know what event triggers this
> > function? If I'm on the wrong list, please give me a hint, what's the
> > correct group for this kind of question.
>
> fbcon believes (quite correctly) that repainting screen is faster than
> doing copyarea because on unaccelerated driver reads from framebuffer
> are 4-10 times slower than writes...
>
> Take a look at updatescrollmode() in fbcon.c - you must persuade this
> function to use SCROLL_*_MOVE, not SCROLL_*_REDRAW.  FBINFO_READS_FAST
> should be sufficient - or you can report fast bitblt + fast panning, or
> fast bitblt + slow imageblit.  If you report no panning + fast bitblt +
> fast imageblit, redraw is used :-(

Uhhh, sounds complicated. All right, I will take a look into fbcon.c. Thank 
you.

Juergen