[MPlayer-dev-eng] [PATCH] libass support in vf_vo

[Evgeniy Stepanov]

Hi,

this is a proposed change to vf_vo.c to allow vo drivers to display 
libass-rendered subtitles directly.

If vo is capable of doing it, it sets VFCAP_EOSD. Seeing that, vf_vo 
initializes libass and starts feeding subtitle images to the vo via 
VFCTRL_DRAW_EOSD.

Some points are unclear to me:
1. What frame resolution the images should be for ? Is it just the screen 
resolution, d_width x d_height, or it depends on vo and should be queried ?
2. There is a draw_osd() function. Is there a reason for it not being a 
VOCTRL ? This way looks much simpler.