[MPlayer-dev-eng] [PATCH] ASS - detect changes to speed up -vo gl

[Reimar Döffinger]

Hello,
On Sun, Oct 29, 2006 at 05:43:21PM +0400, Evgeniy Stepanov wrote:
> On Saturday 28 October 2006 20:05, Jindrich Makovicka wrote:
> > the attached patch adds a subtitle change detection to libass. It is a
> > quite brute force approach, but it significantly reduces the cpu load
> > when using -vo gl, as the texture uploads are costly (at least on
> > nVidia 6600 + build 9625). With the patch, the textures are uploaded
> > only when the EOSD actually changes.
> 
> I suggest removing images_root and making it caller's responsibility to 
> deallocate the list of images. Libass will provide functions for comparing 
> two lists and for deallocating a list. Then, vo_gl can keep ass_images_prev 
> and compare it with the new one.

And who will be responsible for deallocating the images themselves? I
think this way will complicate things a lot.
For vo_gl the simplest solution would be of course if images that are
unchanged would stay in the list at exactly the same position. But that
will become a giant hack, because you would have to tag each image as
"new", "removed" or "unchanged" and also keep the previous dimensions.
I can not think of a really nice solution yet.

Greetings,
Reimar Döffinger