sub: workaround braindead libass API

libass won't use embedded fonts, unless ass_set_fonts() (called by
mp_ass_configure_fonts()) is called. However, we call this function when
the ASS_Renderer is initialized, which is long before the .ass file is
actually loaded. (I'm not sure why it tries to keep 1 ASS_Renderer, but
it always did this.)

Fix by calling mp_ass_configure_fonts() after loading them. This also
means this function will be called multiple times - hopefully this is
harmless (it will reinit fontconfig every time, though).

While we're at it, also initialize the ASS_Renderer lazily.

Fixes #1244.

1 files changed, 14 insertions, 7 deletions

diff --git a/player/sub.c b/player/sub.c
index f694296c90..3d42e0a662 100644
--- a/player/sub.c
+++ b/player/sub.c
@@ -92,11 +92,12 @@ static void add_subtitle_fonts_from_sources(struct MPContext *mpctx)
     }
 }
 
-void init_sub_renderer(struct MPContext *mpctx)
+static void init_sub_renderer(struct MPContext *mpctx)
 {
     struct MPOpts *opts = mpctx->opts;
 
-    uninit_sub_renderer(mpctx);
+    if (mpctx->ass_renderer)
+        return;
 
     if (!mpctx->ass_log)
         mpctx->ass_log = mp_log_new(mpctx, mpctx->global->log, "!libass");
@@ -109,10 +110,6 @@ void init_sub_renderer(struct MPContext *mpctx)
         ass_set_style_overrides(mpctx->ass_library, opts->ass_force_style_list);
 
     mpctx->ass_renderer = ass_renderer_init(mpctx->ass_library);
-    if (mpctx->ass_renderer) {
-        mp_ass_configure_fonts(mpctx->ass_renderer, opts->sub_text_style,
-                               mpctx->global, mpctx->ass_log);
-    }
 }
 
 void uninit_sub_renderer(struct MPContext *mpctx)
@@ -127,9 +124,12 @@ void uninit_sub_renderer(struct MPContext *mpctx)
 
 #else /* HAVE_LIBASS */
 
-void init_sub_renderer(struct MPContext *mpctx) {}
+static void init_sub_renderer(struct MPContext *mpctx) {}
 void uninit_sub_renderer(struct MPContext *mpctx) {}
 
+void mp_ass_configure(ASS_Renderer *priv, struct MPOpts *opts,
+                      struct mp_osd_res *dim) {}
+
 #endif
 
 void uninit_stream_sub_decoders(struct demuxer *demuxer)
@@ -306,11 +306,18 @@ static void reinit_subdec(struct MPContext *mpctx, struct track *track,
     int h = sh_video ? sh_video->disp_h : 0;
     float fps = sh_video ? sh_video->fps : 25;
 
+    init_sub_renderer(mpctx);
+
     sub_set_video_res(dec_sub, w, h);
     sub_set_video_fps(dec_sub, fps);
     sub_set_ass_renderer(dec_sub, mpctx->ass_library, mpctx->ass_renderer);
     sub_init_from_sh(dec_sub, track->stream);
 
+    if (mpctx->ass_renderer) {
+        mp_ass_configure_fonts(mpctx->ass_renderer, opts->sub_text_style,
+                               mpctx->global, mpctx->ass_log);
+    }
+
     // Don't do this if the file has video/audio streams. Don't do it even
     // if it has only sub streams, because reading packets will change the
     // demuxer position.