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

16 files changed, 164 insertions, 105 deletions

diff --git a/command.c b/command.c
index f733bbc0f0..cbac7ebb1a 100644
--- a/command.c
+++ b/command.c
@@ -1487,6 +1487,8 @@ static int mp_property_sub_alignment(m_option_t *prop, int action,
 static int mp_property_sub_visibility(m_option_t *prop, int action,
                                       void *arg, MPContext *mpctx)
 {
+    struct MPOpts *opts = &mpctx->opts;
+
     if (!mpctx->sh_video)
         return M_PROPERTY_UNAVAILABLE;
 
@@ -1500,7 +1502,7 @@ static int mp_property_sub_visibility(m_option_t *prop, int action,
         if (vo_spudec)
             vo_osd_changed(OSDTYPE_SPU);
     default:
-        return m_property_flag(prop, action, arg, &sub_visibility);
+        return m_property_flag(prop, action, arg, &opts->sub_visibility);
     }
 }
 
@@ -1579,34 +1581,28 @@ static int mp_property_sub_scale(m_option_t *prop, int action, void *arg,
         if (!arg)
             return M_PROPERTY_ERROR;
         M_PROPERTY_CLAMP(prop, *(float *) arg);
-#ifdef CONFIG_ASS
         if (opts->ass_enabled)
             opts->ass_font_scale = *(float *) arg;
-#endif
         text_font_scale_factor = *(float *) arg;
         vo_osd_resized();
         return M_PROPERTY_OK;
     case M_PROPERTY_STEP_UP:
     case M_PROPERTY_STEP_DOWN:
-#ifdef CONFIG_ASS
         if (opts->ass_enabled) {
             opts->ass_font_scale += (arg ? *(float *) arg : 0.1) *
                               (action == M_PROPERTY_STEP_UP ? 1.0 : -1.0);
             M_PROPERTY_CLAMP(prop, opts->ass_font_scale);
         }
-#endif
         text_font_scale_factor += (arg ? *(float *) arg : 0.1) *
                                   (action == M_PROPERTY_STEP_UP ? 1.0 : -1.0);
         M_PROPERTY_CLAMP(prop, text_font_scale_factor);
         vo_osd_resized();
         return M_PROPERTY_OK;
     default:
-#ifdef CONFIG_ASS
         if (opts->ass_enabled)
             return m_property_float_ro(prop, action, arg, opts->ass_font_scale);
         else
-#endif
-        return m_property_float_ro(prop, action, arg, text_font_scale_factor);
+            return m_property_float_ro(prop, action, arg, text_font_scale_factor);
     }
 }
 
@@ -2371,7 +2367,8 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
             struct track *track = mpctx->current_track[STREAM_SUB];
             if (track && track->subdata)
                 step_sub(track->subdata, mpctx->video_pts, movement);
-#ifdef CONFIG_ASS
+#if 0
+            // currently not implemented with libass
             if (mpctx->osd->ass_track)
                 sub_delay +=
                     ass_step_sub(mpctx->osd->ass_track,
@@ -2677,7 +2674,7 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
     case MP_CMD_GET_SUB_VISIBILITY:
         if (sh_video) {
             mp_msg(MSGT_GLOBAL, MSGL_INFO,
-                   "ANS_SUB_VISIBILITY=%d\n", sub_visibility);
+                   "ANS_SUB_VISIBILITY=%d\n", opts->sub_visibility);
         }
         break;
 
diff --git a/defaultopts.c b/defaultopts.c
index 8636fe69f0..672dbd5f5c 100644
--- a/defaultopts.c
+++ b/defaultopts.c
@@ -39,6 +39,7 @@ void set_default_mplayer_options(struct MPOpts *opts)
         .audio_id = -1,
         .video_id = -1,
         .sub_id = -1,
+        .sub_visibility = 1,
         .extension_parsing = 1,
         .audio_output_channels = 2,
         .audio_output_format = -1,  // AF_FORMAT_UNKNOWN
diff --git a/libmpcodecs/vf_ass.c b/libmpcodecs/vf_ass.c
index a346f658cf..ad4671fe57 100644
--- a/libmpcodecs/vf_ass.c
+++ b/libmpcodecs/vf_ass.c
@@ -352,19 +352,21 @@ static int render_frame(struct vf_instance *vf, mp_image_t *mpi,
 
 static int put_image(struct vf_instance *vf, mp_image_t *mpi, double pts)
 {
-    struct osd_state *osd = vf->priv->osd;
+    struct vf_priv_s *priv = vf->priv;
+    struct MPOpts *opts = vf->opts;
+    struct osd_state *osd = priv->osd;
     ASS_Image *images = 0;
-    ASS_Renderer *renderer = osd->ass_renderer;
-    bool vs = osd->vsfilter_aspect && vf->opts->ass_vsfilter_aspect_compat;
-    if (sub_visibility && osd->ass_track && (pts != MP_NOPTS_VALUE)) {
-        struct mp_eosd_res dim = { .w = vf->priv->outw, .h = vf->priv->outh,
-                                   .mt = vf->opts->ass_top_margin,
-                                   .mb = vf->opts->ass_bottom_margin };
-        mp_ass_configure(renderer, vf->opts, &dim, 0);
-        ass_set_aspect_ratio(renderer,
-                             vs ? 1. : vf->priv->aspect_correction, 1);
-        images = ass_render_frame(renderer, osd->ass_track,
-                        (pts - osd->sub_offset + sub_delay) * 1000 + .5, NULL);
+    if (pts != MP_NOPTS_VALUE) {
+        osd->dim = (struct mp_eosd_res){ .w = vf->priv->outw,
+                                         .h = vf->priv->outh,
+                                         .mt = opts->ass_top_margin,
+                                         .mb = opts->ass_bottom_margin };
+        osd->normal_scale = vf->priv->aspect_correction;
+        osd->vsfilter_scale = 1;
+        osd->sub_pts = pts - osd->sub_offset;
+        struct sub_bitmaps b;
+        sub_get_bitmaps(osd, &b);
+        images = b.imgs;
     }
 
     prepare_image(vf, mpi);
diff --git a/libmpcodecs/vf_vo.c b/libmpcodecs/vf_vo.c
index 0db75b670e..076850c8c2 100644
--- a/libmpcodecs/vf_vo.c
+++ b/libmpcodecs/vf_vo.c
@@ -30,7 +30,6 @@
 
 #include "libvo/video_out.h"
 
-#include "sub/ass_mp.h"
 #include "sub/sub.h"
 
 struct vf_priv_s {
@@ -122,40 +121,29 @@ static int control(struct vf_instance *vf, int request, void *data)
         };
         return vo_control(video_out, VOCTRL_GET_EQUALIZER, &param) == VO_TRUE;
     }
-#ifdef CONFIG_ASS
     case VFCTRL_INIT_EOSD: {
         vf->priv->prev_visibility = false;
         return CONTROL_TRUE;
     }
 
     case VFCTRL_DRAW_EOSD: {
-        struct mp_eosd_res dim = { 0 };
+        struct osd_state *osd = data;
+        osd->dim = (struct mp_eosd_res){0};
         if (!video_out->config_ok ||
-                vo_control(video_out, VOCTRL_GET_EOSD_RES, &dim) != true) {
+                vo_control(video_out, VOCTRL_GET_EOSD_RES, &osd->dim) != true) {
             vf->priv->prev_visibility = false;
             return CONTROL_FALSE;
         }
-        struct osd_state *osd = data;
-        mp_eosd_images_t images = { NULL, 2 };
-        ASS_Renderer *renderer = osd->ass_renderer;
-        double scale = 1;
-        if (osd->vsfilter_aspect && vf->opts->ass_vsfilter_aspect_compat)
-            scale = vf->priv->scale_ratio;
-        if (sub_visibility && osd->ass_track && (osd->pts != MP_NOPTS_VALUE)) {
-            mp_ass_configure(renderer, vf->opts, &dim,
-                             vf->default_caps & VFCAP_EOSD_UNSCALED);
-            ass_set_aspect_ratio(renderer, scale, 1);
-            images.imgs = ass_render_frame(renderer, osd->ass_track,
-                                           (osd->pts + sub_delay) * 1000 + .5,
-                                           &images.changed);
-            if (!vf->priv->prev_visibility)
-                images.changed = 2;
-            vf->priv->prev_visibility = true;
-        } else
-            vf->priv->prev_visibility = false;
+        osd->normal_scale = 1;
+        osd->vsfilter_scale = vf->priv->scale_ratio;
+        osd->unscaled = vf->default_caps & VFCAP_EOSD_UNSCALED;
+        struct sub_bitmaps images;
+        sub_get_bitmaps(osd, &images);
+        if (!vf->priv->prev_visibility)
+            images.changed = 2;
+        vf->priv->prev_visibility = true;
         return vo_control(video_out, VOCTRL_DRAW_EOSD, &images) == VO_TRUE;
     }
-#endif
     }
     return CONTROL_UNKNOWN;
 }
diff --git a/libvo/eosd_packer.h b/libvo/eosd_packer.h
index e207a4a2dd..eaacd0223f 100644
--- a/libvo/eosd_packer.h
+++ b/libvo/eosd_packer.h
@@ -23,6 +23,7 @@
 #include <stdbool.h>
 
 #include "sub/ass_mp.h"
+#include "sub/dec_sub.h"
 
 // Pool of surfaces
 struct eosd_surface {
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;
diff --git a/mplayer.c b/mplayer.c
index 0734defbd6..5b02e33588 100644
--- a/mplayer.c
+++ b/mplayer.c
@@ -605,8 +605,13 @@ void uninit_player(struct MPContext *mpctx, unsigned int mask)
 
     if (mask & INITIALIZED_SUB) {
         mpctx->initialized_flags &= ~INITIALIZED_SUB;
+        struct track *track = mpctx->current_track[STREAM_SUB];
+        // One of these was active; they can't be both active.
+        assert(!(mpctx->sh_sub && (track && track->sh_sub)));
         if (mpctx->sh_sub)
             sub_switchoff(mpctx->sh_sub, mpctx->osd);
+        if (track && track->sh_sub)
+            sub_switchoff(track->sh_sub, mpctx->osd);
         cleanup_demux_stream(mpctx, STREAM_SUB);
         reset_subtitles(mpctx);
     }
@@ -623,10 +628,7 @@ void uninit_player(struct MPContext *mpctx, unsigned int mask)
         for (int i = 0; i < mpctx->num_tracks; i++) {
             struct track *track = mpctx->tracks[i];
             sub_free(track->subdata);
-#ifdef CONFIG_ASS
-            if (track->ass_track)
-                ass_free_track(track->ass_track);
-#endif
+            talloc_free(track->sh_sub);
             talloc_free(track);
         }
         mpctx->num_tracks = 0;
@@ -1040,16 +1042,16 @@ void add_subtitles(struct MPContext *mpctx, char *filename, float fps,
 {
     struct MPOpts *opts = &mpctx->opts;
     sub_data *subd = NULL;
-    struct ass_track *asst = NULL;
-    bool is_native_ass = false;
+    struct sh_sub *sh = NULL;
 
     if (filename == NULL)
         return;
 
-#ifdef CONFIG_ASS
     if (opts->ass_enabled) {
-        asst = mp_ass_read_stream(mpctx->ass_library, filename, sub_cp);
-        is_native_ass = asst;
+#ifdef CONFIG_ASS
+        struct ass_track *asst = mp_ass_read_stream(mpctx->ass_library,
+                                                    filename, sub_cp);
+        bool is_native_ass = asst;
         if (!asst) {
             subd = sub_read_file(filename, fps, &mpctx->opts);
             if (subd) {
@@ -1058,12 +1060,14 @@ void add_subtitles(struct MPContext *mpctx, char *filename, float fps,
                 subd = NULL;
             }
         }
-    } else
+        if (asst)
+            sh = sd_ass_create_from_track(asst, is_native_ass, opts);
 #endif
-    subd = sub_read_file(filename, fps, &mpctx->opts);
+    } else
+        subd = sub_read_file(filename, fps, &mpctx->opts);
 
 
-    if (!asst && !subd) {
+    if (!sh && !subd) {
         mp_tmsg(MSGT_CPLAYER, noerr ? MSGL_WARN : MSGL_ERR,
                 "Cannot load subtitles: %s\n", filename);
         return;
@@ -1072,11 +1076,11 @@ void add_subtitles(struct MPContext *mpctx, char *filename, float fps,
     struct track *track = talloc_ptrtype(NULL, track);
     *track = (struct track) {
         .type = STREAM_SUB,
+        .title = talloc_strdup(track, filename),
         .user_tid = find_new_tid(mpctx, STREAM_SUB),
         .demuxer_id = -1,
         .is_external = true,
-        .ass_track = asst,
-        .native_ass_track = is_native_ass,
+        .sh_sub = sh,
         .subdata = subd,
     };
     MP_TARRAY_APPEND(mpctx, mpctx->tracks, mpctx->num_tracks, track);
@@ -1743,10 +1747,6 @@ double playing_audio_pts(struct MPContext *mpctx)
 
 static void reset_subtitles(struct MPContext *mpctx)
 {
-    struct sh_sub *sh_sub = mpctx->sh_sub;
-
-    if (sh_sub)
-        sub_reset(sh_sub, mpctx->osd);
     sub_clear_text(&mpctx->subs, MP_NOPTS_VALUE);
     if (vo_sub)
         set_osd_subtitle(mpctx, NULL);
@@ -1941,7 +1941,6 @@ static void reinit_subs(struct MPContext *mpctx)
 
     init_demux_stream(mpctx, STREAM_SUB);
 
-    mpctx->osd->ass_track = NULL;
     vobsub_id = -1;
 
     if (!track)
@@ -1967,20 +1966,17 @@ static void reinit_subs(struct MPContext *mpctx)
 
     if (track->vobsub_id_plus_one) {
         vobsub_id = track->vobsub_id_plus_one - 1;
-    } else if (track->subdata || track->ass_track) {
+    } else if (track->subdata || track->sh_sub) {
 #ifdef CONFIG_ASS
-        if (opts->ass_enabled && track->ass_track) {
-            mpctx->osd->ass_track = track->ass_track;
-            mpctx->osd->vsfilter_aspect = track->native_ass_track;
-        }
+        if (opts->ass_enabled && track->sh_sub)
+            sub_init(track->sh_sub, mpctx->osd);
 #endif
         vo_osd_changed(OSDTYPE_SUBTITLE);
     } else if (track->stream) {
         if (mpctx->sh_sub->type == 'v')
             init_vo_spudec(mpctx);
-        else {
+        else
             sub_init(mpctx->sh_sub, mpctx->osd);
-        }
     }
 }
 
@@ -2365,11 +2361,9 @@ int reinit_video_chain(struct MPContext *mpctx)
 
     sh_video->vfilter = append_filters(sh_video->vfilter, opts->vf_settings);
 
-#ifdef CONFIG_ASS
     if (opts->ass_enabled)
         sh_video->vfilter->control(sh_video->vfilter, VFCTRL_INIT_EOSD,
                                    mpctx->ass_library);
-#endif
 
     init_best_video_codec(sh_video, video_codec_list, video_fm_list);
 
@@ -2616,7 +2610,10 @@ static int redraw_osd(struct MPContext *mpctx)
         return -1;
     if (vo_redraw_frame(mpctx->video_out) < 0)
         return -1;
-    mpctx->osd->pts = mpctx->video_pts - mpctx->osd->sub_offset;
+    mpctx->osd->sub_pts = mpctx->video_pts;
+    if (mpctx->osd->sub_pts != MP_NOPTS_VALUE)
+        mpctx->osd->sub_pts += sub_delay - mpctx->osd->sub_offset;
+
     if (!(sh_video->output_flags & VFCAP_EOSD_FILTER))
         vf->control(vf, VFCTRL_DRAW_EOSD, mpctx->osd);
     vf->control(vf, VFCTRL_DRAW_OSD, mpctx->osd);
@@ -3215,7 +3212,9 @@ static void run_playloop(struct MPContext *mpctx)
         update_subtitles(mpctx, sh_video->pts);
         update_osd_msg(mpctx);
         struct vf_instance *vf = sh_video->vfilter;
-        mpctx->osd->pts = mpctx->video_pts - mpctx->osd->sub_offset;
+        mpctx->osd->sub_pts = mpctx->video_pts;
+        if (mpctx->osd->sub_pts != MP_NOPTS_VALUE)
+            mpctx->osd->sub_pts += sub_delay - mpctx->osd->sub_offset;
         vf->control(vf, VFCTRL_DRAW_EOSD, mpctx->osd);
         vf->control(vf, VFCTRL_DRAW_OSD, mpctx->osd);
         vo_osd_reset_changed();
@@ -4048,7 +4047,6 @@ terminate_playback:  // don't jump here after ao/vo/getch initialization!
 
     vo_sub = NULL;
 #ifdef CONFIG_ASS
-    mpctx->osd->ass_track = NULL;
     if (mpctx->osd->ass_renderer)
         ass_renderer_done(mpctx->osd->ass_renderer);
     mpctx->osd->ass_renderer = NULL;
diff --git a/options.h b/options.h
index 307f9682b3..2b06535afd 100644
--- a/options.h
+++ b/options.h
@@ -74,6 +74,7 @@ typedef struct MPOpts {
     int sub_id;
     char **audio_lang;
     char **sub_lang;
+    int sub_visibility;
     int hr_mp3_seek;
     char *quvi_format;
 
diff --git a/sub/ass_mp.h b/sub/ass_mp.h
index 095cf4311d..3cfbe147b7 100644
--- a/sub/ass_mp.h
+++ b/sub/ass_mp.h
@@ -61,10 +61,4 @@ typedef struct ass_image {
 
 #endif
 
-typedef struct {
-    ASS_Image *imgs;
-    int changed;
-} mp_eosd_images_t;
-
-
 #endif                          /* MPLAYER_ASS_MP_H */
diff --git a/sub/dec_sub.c b/sub/dec_sub.c
index 7528e90e58..c710ff575a 100644
--- a/sub/dec_sub.c
+++ b/sub/dec_sub.c
@@ -22,8 +22,9 @@
 
 #include "config.h"
 #include "libmpdemux/stheader.h"
-#include "sd.h"
-#include "dec_sub.h"
+#include "sub/sd.h"
+#include "sub/sub.h"
+#include "sub/dec_sub.h"
 #include "options.h"
 
 extern const struct sd_functions sd_ass;
@@ -33,6 +34,7 @@ void sub_init(struct sh_sub *sh, struct osd_state *osd)
 {
     struct MPOpts *opts = sh->opts;
 
+    assert(!osd->sh_sub);
 #ifdef CONFIG_ASS
     if (opts->ass_enabled && is_text_sub(sh->type))
         sh->sd_driver = &sd_ass;
@@ -42,6 +44,8 @@ void sub_init(struct sh_sub *sh, struct osd_state *osd)
     if (sh->sd_driver) {
         if (sh->sd_driver->init(sh, osd) < 0)
             return;
+        osd->sh_sub = sh;
+        osd->changed_outside_sd = true;
         sh->initialized = true;
         sh->active = true;
     }
@@ -54,6 +58,22 @@ void sub_decode(struct sh_sub *sh, struct osd_state *osd, void *data,
         sh->sd_driver->decode(sh, osd, data, data_len, pts, duration);
 }
 
+void sub_get_bitmaps(struct osd_state *osd, struct sub_bitmaps *res)
+{
+    struct MPOpts *opts = osd->opts;
+
+    *res = (struct sub_bitmaps){.imgs = NULL, .changed = 2};
+    if (!opts->sub_visibility || !osd->sh_sub || !osd->sh_sub->active) {
+        osd->changed_outside_sd = true;
+        return;
+    }
+    if (osd->sh_sub->sd_driver->get_bitmaps)
+        osd->sh_sub->sd_driver->get_bitmaps(osd->sh_sub, osd, res);
+    if (osd->changed_outside_sd)
+        res->changed = 2;
+    osd->changed_outside_sd = false;
+}
+
 void sub_reset(struct sh_sub *sh, struct osd_state *osd)
 {
     if (sh->active && sh->sd_driver->reset)
@@ -62,8 +82,11 @@ void sub_reset(struct sh_sub *sh, struct osd_state *osd)
 
 void sub_switchoff(struct sh_sub *sh, struct osd_state *osd)
 {
-    if (sh->active && sh->sd_driver->switch_off)
+    if (sh->active && sh->sd_driver->switch_off) {
+        assert(osd->sh_sub == sh);
         sh->sd_driver->switch_off(sh, osd);
+        osd->sh_sub = NULL;
+    }
     sh->active = false;
 }
 
diff --git a/sub/dec_sub.h b/sub/dec_sub.h
index e58ad65550..f09b555685 100644
--- a/sub/dec_sub.h
+++ b/sub/dec_sub.h
@@ -3,12 +3,18 @@
 
 struct sh_sub;
 struct osd_state;
+struct ass_track;
 
 typedef struct mp_eosd_res {
     int w, h; // screen dimensions, including black borders
     int mt, mb, ml, mr; // borders (top, bottom, left, right)
 } mp_eosd_res_t;
 
+typedef struct sub_bitmaps {
+    struct ass_image *imgs;
+    int changed;
+} mp_eosd_images_t;
+
 static inline bool is_text_sub(int type)
 {
     return type == 't' || type == 'm' || type == 'a';
@@ -16,9 +22,14 @@ static inline bool is_text_sub(int type)
 
 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 sub_bitmaps *res);
 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);
+
 #endif
diff --git a/sub/osd_libass.c b/sub/osd_libass.c
index 9f15173442..e770215ce6 100644
--- a/sub/osd_libass.c
+++ b/sub/osd_libass.c
@@ -331,9 +331,11 @@ void vo_update_text_progbar(struct osd_state *osd, mp_osd_obj_t* obj)
 
 void vo_update_text_sub(struct osd_state *osd, mp_osd_obj_t* obj)
 {
+    struct MPOpts *opts = osd->opts;
+
     obj->flags |= OSDFLAG_CHANGED | OSDFLAG_VISIBLE;
 
-    if (!vo_sub || !sub_visibility) {
+    if (!vo_sub || !opts->sub_visibility) {
         obj->flags &= ~OSDFLAG_VISIBLE;
         return;
     }
diff --git a/sub/sd.h b/sub/sd.h
index c36110277b..7a0740f823 100644
--- a/sub/sd.h
+++ b/sub/sd.h
@@ -3,11 +3,14 @@
 
 struct osd_state;
 struct sh_sub;
+struct sub_bitmaps;
 
 struct sd_functions {
     int  (*init)(struct sh_sub *sh, struct osd_state *osd);
     void (*decode)(struct sh_sub *sh, struct osd_state *osd,
                    void *data, int data_len, double pts, double duration);
+    void (*get_bitmaps)(struct sh_sub *sh, struct osd_state *osd,
+                        struct sub_bitmaps *res);
     void (*reset)(struct sh_sub *sh, struct osd_state *osd);
     void (*switch_off)(struct sh_sub *sh, struct osd_state *osd);
     void (*uninit)(struct sh_sub *sh);
diff --git a/sub/sd_ass.c b/sub/sd_ass.c
index f54c18e805..72dee06018 100644
--- a/sub/sd_ass.c
+++ b/sub/sd_ass.c
@@ -23,6 +23,7 @@
 
 #include "talloc.h"
 
+#include "options.h"
 #include "mpcommon.h"
 #include "mp_msg.h"
 #include "libmpdemux/stheader.h"
@@ -33,6 +34,7 @@
 
 struct sd_ass_priv {
     struct ass_track *ass_track;
+    bool vsfilter_aspect;
     bool incomplete_event;
 };
 
@@ -61,9 +63,7 @@ static int init(struct sh_sub *sh, struct osd_state *osd)
             ctx->ass_track = mp_ass_default_track(osd->ass_library, sh->opts);
     }
 
-    assert(osd->ass_track == NULL);
-    osd->ass_track = ctx->ass_track;
-    osd->vsfilter_aspect = sh->type == 'a';
+    ctx->vsfilter_aspect = sh->type == 'a';
     return 0;
 }
 
@@ -125,6 +125,25 @@ static void decode(struct sh_sub *sh, struct osd_state *osd, void *data,
     event->Text = strdup(buf);
 }
 
+static void get_bitmaps(struct sh_sub *sh, struct osd_state *osd,
+                        struct sub_bitmaps *res)
+{
+    struct sd_ass_priv *ctx = sh->context;
+    struct MPOpts *opts = osd->opts;
+
+    if (osd->sub_pts == MP_NOPTS_VALUE)
+        return;
+
+    double scale = osd->normal_scale;
+    if (ctx->vsfilter_aspect && opts->ass_vsfilter_aspect_compat)
+        scale = osd->vsfilter_scale;
+    ASS_Renderer *renderer = osd->ass_renderer;
+    mp_ass_configure(renderer, opts, &osd->dim, osd->unscaled);
+    ass_set_aspect_ratio(renderer, scale, 1);
+    res->imgs = ass_render_frame(renderer, ctx->ass_track,
+                                 osd->sub_pts * 1000 + .5, &res->changed);
+}
+
 static void reset(struct sh_sub *sh, struct osd_state *osd)
 {
     struct sd_ass_priv *ctx = sh->context;
@@ -133,12 +152,6 @@ static void reset(struct sh_sub *sh, struct osd_state *osd)
     ctx->incomplete_event = false;
 }
 
-static void switch_off(struct sh_sub *sh, struct osd_state *osd)
-{
-    reset(sh, osd);
-    osd->ass_track = NULL;
-}
-
 static void uninit(struct sh_sub *sh)
 {
     struct sd_ass_priv *ctx = sh->context;
@@ -150,7 +163,27 @@ static void uninit(struct sh_sub *sh)
 const struct sd_functions sd_ass = {
     .init = init,
     .decode = decode,
+    .get_bitmaps = get_bitmaps,
     .reset = reset,
-    .switch_off = switch_off,
+    .switch_off = reset,
     .uninit = uninit,
 };
+
+
+struct sh_sub *sd_ass_create_from_track(struct ass_track *track,
+                                        bool vsfilter_aspect,
+                                        struct MPOpts *opts)
+{
+    struct sh_sub *sh = talloc(NULL, struct sh_sub);
+    *sh = (struct sh_sub) {
+        .opts = opts,
+        .type = 'a',
+        .sd_driver = &sd_ass,
+        .context = talloc_struct(sh, struct sd_ass_priv, {
+            .ass_track = track,
+            .vsfilter_aspect = vsfilter_aspect,
+        }),
+        .initialized = true,
+    };
+    return sh;
+}
diff --git a/sub/sub.c b/sub/sub.c
index 67413c936e..5b5920d23c 100644
--- a/sub/sub.c
+++ b/sub/sub.c
@@ -30,6 +30,7 @@
 #include "osdep/timer.h"
 
 #include "talloc.h"
+#include "options.h"
 #include "mplayer.h"
 #include "mp_msg.h"
 #include "libvo/video_out.h"
@@ -170,6 +171,7 @@ static int osd_update_ext(struct osd_state *osd, int dxs, int dys,
                           int left_border, int top_border, int right_border,
                           int bottom_border, int orig_w, int orig_h)
 {
+    struct MPOpts *opts = osd->opts;
     mp_osd_obj_t* obj=vo_osd_list;
     int chg=0;
 
@@ -190,7 +192,7 @@ static int osd_update_ext(struct osd_state *osd, int dxs, int dys,
 	    vo_update_text_progbar(osd, obj);
 	    break;
 	case OSDTYPE_SPU:
-	    if(sub_visibility && vo_spudec && spudec_visible(vo_spudec)){
+	    if (opts->sub_visibility && vo_spudec && spudec_visible(vo_spudec)){
 	        vo_update_spudec_sub(osd, obj);
 		obj->flags|=OSDFLAG_VISIBLE|OSDFLAG_CHANGED;
 	    }
diff --git a/sub/sub.h b/sub/sub.h
index 3ad8dc9217..8a8a2ab941 100644
--- a/sub/sub.h
+++ b/sub/sub.h
@@ -62,15 +62,19 @@ typedef struct mp_osd_obj_s {
 struct osd_state {
     struct ass_library *ass_library;
     struct ass_renderer *ass_renderer;
-    int w, h;
-    char *osd_text;
-    struct ass_track *ass_track;
-    double pts;
+    struct sh_sub *sh_sub;
+    bool changed_outside_sd;
+    double sub_pts;
     double sub_offset;
-    bool vsfilter_aspect;
+    struct mp_eosd_res dim;
+    double normal_scale;
+    double vsfilter_scale;
+    bool unscaled;
 
     struct ass_renderer *osd_render;
     struct ass_library *osd_ass_library;
+    char *osd_text;
+    int w, h;
 
     struct MPOpts *opts;
 };
@@ -113,7 +117,6 @@ extern char *sub_cp;
 extern int sub_pos;
 extern int sub_width_p;
 extern int sub_alignment;
-extern int sub_visibility;
 extern int sub_bg_color; /* subtitles background color */
 extern int sub_bg_alpha;
 extern int spu_alignment;