[vlc-devel] [PATCH 3/3] Subtitles: fix misplaced subs on video resize

[Salah-Eddin Shaban]

When handling of overlapped subtitles was introduced all subtitles were marked as absolute on first rendering.
This caused the position to be calculated only once and not be updated when the video size changed.
---
 include/vlc_subpicture.h            |  8 ++++++++
 src/misc/subpicture.c               |  6 ++++++
 src/video_output/vout_subpictures.c | 10 ++++------
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/include/vlc_subpicture.h b/include/vlc_subpicture.h
index aa2ed0d..3c07a2a 100644
--- a/include/vlc_subpicture.h
+++ b/include/vlc_subpicture.h
@@ -61,6 +61,14 @@ struct subpicture_region_t
 
     int             i_x;                             /**< position of region */
     int             i_y;                             /**< position of region */
+
+    /**
+     * used to save region position in case it has to be changed
+     * temporarily e.g. because of overlapped subtitles
+     */
+    int             i_original_x;
+    int             i_original_y;
+
     int             i_align;                  /**< alignment within a region */
     int             i_alpha;                               /**< transparency */
 
diff --git a/src/misc/subpicture.c b/src/misc/subpicture.c
index f18be17..9f8eb1c 100644
--- a/src/misc/subpicture.c
+++ b/src/misc/subpicture.c
@@ -170,6 +170,12 @@ void subpicture_Update( subpicture_t *p_subpicture,
 
     p_upd->pf_update( p_subpicture, p_fmt_src, p_fmt_dst, i_ts );
 
+    for( subpicture_region_t *r = p_subpicture->p_region; r; r = r->p_next )
+    {
+        r->i_original_x = r->i_x;
+        r->i_original_y = r->i_y;
+    }
+
     video_format_Clean( &p_private->src );
     video_format_Clean( &p_private->dst );
 
diff --git a/src/video_output/vout_subpictures.c b/src/video_output/vout_subpictures.c
index bbccaf4..cc3bf57 100644
--- a/src/video_output/vout_subpictures.c
+++ b/src/video_output/vout_subpictures.c
@@ -1024,13 +1024,13 @@ static subpicture_t *SpuRenderSubpictures(spu_t *spu,
             sys->text->fmt_out.video.i_visible_height = subpic->i_original_picture_height;
         }
 
-        /* Render all regions
-         * We always transform non absolute subtitle into absolute one on the
-         * first rendering to allow good subtitle overlap support.
-         */
+        /* Render all regions */
         for (region = subpic->p_region; region != NULL; region = region->p_next) {
             spu_area_t area;
 
+            region->i_x = region->i_original_x;
+            region->i_y = region->i_original_y;
+
             /* Compute region scale AR */
             video_format_t region_fmt = region->fmt;
             if (region_fmt.i_sar_num <= 0 || region_fmt.i_sar_den <= 0) {
@@ -1072,8 +1072,6 @@ static subpicture_t *SpuRenderSubpictures(spu_t *spu,
                     subtitle_area[subtitle_area_count++] = area;
             }
         }
-        if (subpic->b_subtitle && subpic->p_region)
-            subpic->b_absolute = true;
     }
 
     /* */
-- 
2.10.2