sub: allow rendering OSD in ASS image format directly, simplify

Before this commit, the OSD was drawn using libass, but the resulting
bitmaps were converted to the internal mplayer OSD format. We want to
get rid of the old OSD format, because it's monochrome, and can't even
be rendered directly using modern video output methods (like with
OpenGL/Direct3D/VDPAU).

Change it so that VOs can get the ASS images directly, without
additional conversions. (This also has the consequence that the OSD can
render colors now.) Currently, this is vo_gl3 only. The other VOs still
use the old method. Also, the old OSD format is still used for all VOs
with DVD subtitles (spudec).

Rewrite sub.c. Remove all the awkward flags and bounding boxes and
change detection things. It turns out that much of that isn't needed.

Move code related to converting subtitle images to img_convert.c. (It
has to be noted that all of these conversions were already done before
in some places, and that the new code actually makes less use of them.)

1 files changed, 35 insertions, 0 deletions

diff --git a/sub/ass_mp.c b/sub/ass_mp.c
index 202664578b..5766a847f8 100644
--- a/sub/ass_mp.c
+++ b/sub/ass_mp.c
@@ -264,6 +264,41 @@ void mp_ass_configure_fonts(ASS_Renderer *priv)
     free(family);
 }
 
+void mp_ass_render_frame(ASS_Renderer *renderer, ASS_Track *track, double time,
+                         struct sub_bitmap **parts, struct sub_bitmaps *res)
+{
+    int changed;
+    res->imgs = ass_render_frame(renderer, track, time, &changed);
+    if (changed == 2)
+        res->bitmap_id = ++res->bitmap_pos_id;
+    else if (changed)
+        res->bitmap_pos_id++;
+    res->format = SUBBITMAP_LIBASS;
+
+    res->parts = *parts;
+    res->num_parts = 0;
+    int num_parts_alloc = MP_TALLOC_ELEMS(res->parts);
+    for (struct ass_image *img = res->imgs; img; img = img->next) {
+        if (img->w == 0 || img->h == 0)
+            continue;
+        if (res->num_parts >= num_parts_alloc) {
+            num_parts_alloc = FFMAX(num_parts_alloc * 2, 32);
+            res->parts = talloc_realloc(NULL, res->parts, struct sub_bitmap,
+                                        num_parts_alloc);
+        }
+        struct sub_bitmap *p = &res->parts[res->num_parts];
+        p->bitmap = img->bitmap;
+        p->stride = img->stride;
+        p->libass.color = img->color;
+        p->dw = p->w = img->w;
+        p->dh = p->h = img->h;
+        p->x = img->dst_x;
+        p->y = img->dst_y;
+        res->num_parts++;
+    }
+    *parts = res->parts;
+}
+
 static int map_ass_level[] = {
     MSGL_ERR,           // 0 "FATAL errors"
     MSGL_WARN,