sub: pack libass bitmaps directly in sd_ass.c and osd_libass.c

Change all producer of libass images to packing the bitmaps into a
single larger bitmap directly when they're output. This is supposed to
help working towards refcounted sub bitmaps.

This will reduce performance for VOs like vo_xv, but not for vo_opengl.
vo_opengl simply will pick up the pre-packed sub bitmaps, and skip
packing them again. vo_xv will copy and pack the sub bitmaps
unnecessarily - but if we want sub bitmap refcounting, they'd have to be
copied anyway.

The packing code cannot be removed yet from vo_opengl, because there are
certain corner cases that still produce unpackad other sub bitmaps.
Actual refcounting will also require more work.

1 files changed, 1 insertions, 0 deletions

diff --git a/sub/osd.h b/sub/osd.h
index 7cfc695873..ade546f4f4 100644
--- a/sub/osd.h
+++ b/sub/osd.h
@@ -69,6 +69,7 @@ struct sub_bitmaps {
     // parts[].bitmap pointer points into the image data here (and stride will
     // correspond to packed->stride[0]).
     //  SUBBITMAP_RGBA: IMGFMT_BGRA (exact match)
+    //  SUBBITMAP_LIBASS: IMGFMT_Y8 (not the same, but compatible layout)
     // Other formats have this set to NULL.
     struct mp_image *packed;