osd_libass: update styles when OSD changes PlayRes

The OSD style settings depend on the PlayRes, simply because all style
values are implicitly scaled by the PlayResY in libass. Also, the OSC
changes the PlayResY in certain situations, so something could go wrong.
But not sure if this actually matters in practice.

1 files changed, 5 insertions, 3 deletions

diff --git a/sub/ass_mp.c b/sub/ass_mp.c
index 5ae85c0d06..44b59e34d5 100644
--- a/sub/ass_mp.c
+++ b/sub/ass_mp.c
@@ -43,9 +43,11 @@ void mp_ass_set_style(ASS_Style *style, double res_y,
                       const struct osd_style_opts *opts)
 {
     if (opts->font) {
-        free(style->FontName);
-        style->FontName = strdup(opts->font);
-        style->treat_fontname_as_pattern = 1;
+        if (!style->FontName || strcmp(style->FontName, opts->font) != 0) {
+            free(style->FontName);
+            style->FontName = strdup(opts->font);
+            style->treat_fontname_as_pattern = 1;
+        }
     }
 
     // libass_font_size = FontSize * (window_height / res_y)