sub: redo how -no-ass is handled

The -no-ass switch used to disable any use of libass for text subtitles.
This is not really the case anymore, because libass is now always
involved when rendering text. The only remaining use of -no-ass is
disabling styling or showing subtitles on the terminal. On the other
hand, the old subtitle rendering path is a big reason why the subtitle
code is still a big mess with an awful number of obscure special cases.

In order to simplify it, remove the old subtitle rendering code, and
always go through sd_ass.c. Basically, we use ASS_Track as central data
structure for storing text subtitles instead of struct sub_data. This
also makes libass mandatory for all text subs, even if they are printed
to the terminal in -no-video mode. (We could add something like sd_text
to avoid this, but it's not worth the trouble.)

struct sub_data and subreader.c are still around, even its ASS/SSA
reader. But struct sub_data is freed right after converting it to
ASS_Track. The internal ASS reader actually can handle some obscure
cases libass can't, like files encoded in UTF-16.

1 files changed, 3 insertions, 2 deletions

diff --git a/sub/dec_sub.h b/sub/dec_sub.h
index 593eac1e03..52fa05eebc 100644
--- a/sub/dec_sub.h
+++ b/sub/dec_sub.h
@@ -14,18 +14,19 @@ bool is_text_sub(const char *t);
 bool is_ass_sub(const char *t);
 bool is_dvd_sub(const char *t);
 
+bool sub_accept_packets_in_advance(struct sh_sub *sh);
 void sub_decode(struct sh_sub *sh, struct osd_state *osd, void *data,
                 int data_len, double pts, double duration);
 void sub_get_bitmaps(struct osd_state *osd, struct mp_osd_res dim, double pts,
                      struct sub_bitmaps *res);
+char *sub_get_text(struct osd_state *osd, double pts);
 void sub_init(struct sh_sub *sh, struct osd_state *osd);
 void sub_reset(struct sh_sub *sh, struct osd_state *osd);
 void sub_switchoff(struct sh_sub *sh, struct osd_state *osd);
 void sub_uninit(struct sh_sub *sh);
 
 struct sh_sub *sd_ass_create_from_track(struct ass_track *track,
-                                        bool vsfilter_aspect,
-                                        struct MPOpts *opts);
+                                        const char *codec, struct MPOpts *opts);
 
 #ifdef CONFIG_ASS
 struct ass_track *sub_get_ass_track(struct osd_state *osd);