[MPlayer-dev-eng] [PATCH] libass support for VDPAU

[Reimar Döffinger]

On Fri, Feb 06, 2009 at 11:24:36PM +0100, Grigori G wrote:
> On Fri, 6 Feb 2009 23:01:58 +0100, Reimar Döffinger
> <Reimar.Doeffinger at stud.uni-karlsruhe.de> wrote:
> > Having many hundreds of tiny textures cause serious performance issues
> > with -vo gl.
> 
> And it's the same here, basically. The code tries to reuse bitmapsurfaces
> as much as possible though.

Reusing them does not reduce the number. -vo gl collects all the small
ones in two large textures. I have no idea if that is necessary/useful
here, just saying.

> The real problem is how libass rendering works, software-rendering to a
> single RGBA bitmap would probably be faster and avoid a few of the
> problems libass has at the moment.

That vastly depends on the subtitle, but I doubt it. A RGBA bitmap at
display resolution and possibly 60 Hz needs _extremly_ much bandwidth.
There is also the question how often the subtitle components will just
be moved but the data not actually changed.
Still, there are probably representations that work better with hardware
rendering, even though I doubt full-size RGBA is one of those,