[MPlayer-users] ssa/ass rendering uses lots of cpu with -vo gl

[Reimar Döffinger]

On Sat, Jan 22, 2011 at 09:58:07PM +0100, Nicolas George wrote:
> If the problem is what you think it is, maybe changing it to:
> 
> for each EOSD image element
>   find some room for it in one of the textures
>   copy the bitmap to a memory buffer associated to that texture
> upload the necessary parts of the memory buffers
> 
> Or maybe you already tried that.

Yes, I meant to say that I tried exactly that, and depending on
how exactly I did it it (MapBuffer vs. BufferSubData) it was the
same speed or slower. That's why I blame the driver.
There are other things that could be tried, but it tends to be quite a bit
of effort and not that likely to help.
For this specific case, checking for each part seperately whether
it was actually changed would help.
In general it could help for libass to merge non-overlapping glyphs,
but to a degree these all optimize only some special-cases.