subs: always use sub decoder framework for libass rendering

Remove subtitle selection code setting osd->ass_track directly and
vf_ass/vf_vo code rendering the track directly with libass. Instead,
do track selection and rendering with dec_sub.c functions.

Before, mpctx->set_of_ass_tracks[] contained bare libass tracks
generated from external subtitle files. For use with dec_sub.c, it now
contains struct sh_sub instances with decoder already initialized.

This commit breaks the sub_step command ('g' and 'y' keys) for
libass-rendered subtitles. It could be fixed, but it's so useless -
especially as with the existing implementation there's no practical
way to get subtitle delay back to normal after using it - that I
didn't bother.

Conflicts:
	command.c
	mp_core.h
	mplayer.c

1 files changed, 2 insertions, 2 deletions

diff --git a/mp_core.h b/mp_core.h
index ea21752767..e42beb40c5 100644
--- a/mp_core.h
+++ b/mp_core.h
@@ -107,8 +107,8 @@ struct track {
     //       fields. The data is stored in stream->sub this case.
 
     // External text subtitle using libass subtitle renderer.
-    struct ass_track *ass_track;
-    bool native_ass_track;
+    // The sh_sub is a dummy and doesn't belong to a demuxer.
+    struct sh_sub *sh_sub;
 
     // External text subtitle using non-libass subtitle renderer.
     struct sub_data *subdata;