core, vo: modify OSD redraw architecture, support EOSD

Previously the core sent VFCTRL_REDRAW_OSD to change OSD contents over
the current frame. Change this to VFCTRL_REDRAW_FRAME followed by
normal EOSD and OSD drawing calls, then vo_flip_page(). The new
version supports changing EOSD contents for libass-rendered subtitles
and simplifies the redraw support code needed per VO. vo_xv doesn't
support EOSD changes because it relies on vf_ass to render EOSD
contents earlier in the filter chain.

vo_xv logic is additionally simplified because the previous commit
removed the need to track the status of current and next images
separately (now each frame is guaranteed to become "visible" soon
after we receive it as "next", with no VO code running in the interval
between).

1 files changed, 17 insertions, 29 deletions

diff --git a/libvo/vo_xv.c b/libvo/vo_xv.c
index 694dbc048a..4d1a354937 100644
--- a/libvo/vo_xv.c
+++ b/libvo/vo_xv.c
@@ -89,10 +89,8 @@ struct xvctx {
     int current_ip_buf;
     int num_buffers;
     int total_buffers;
-    int have_visible_image_copy;
-    int have_next_image_copy;
-    int unchanged_visible_image;
-    int unchanged_next_image;
+    bool have_image_copy;
+    bool unchanged_image;
     int visible_buf;
     XvImage *xvimage[NUM_BUFFERS + 1];
     uint32_t image_width;
@@ -227,8 +225,7 @@ static int config(struct vo *vo, uint32_t width, uint32_t height,
     }
 
     ctx->visible_buf = -1;
-    ctx->have_visible_image_copy = false;
-    ctx->have_next_image_copy = false;
+    ctx->have_image_copy = false;
 
     /* check image formats */
     ctx->xv_format = 0;
@@ -447,26 +444,21 @@ static void draw_osd(struct vo *vo, struct osd_state *osd)
                                                       vo->panscan_x),
                   ctx->image_height, ctx->draw_alpha_fnc, vo);
     if (ctx->osd_objects_drawn)
-        ctx->unchanged_next_image = false;
+        ctx->unchanged_image = false;
 }
 
-static int redraw_osd(struct vo *vo, struct osd_state *osd)
+static int redraw_frame(struct vo *vo)
 {
     struct xvctx *ctx = vo->priv;
 
-    if (ctx->have_visible_image_copy)
+    if (ctx->have_image_copy)
         copy_backup_image(vo, ctx->visible_buf, ctx->num_buffers);
-    else if (ctx->unchanged_visible_image) {
+    else if (ctx->unchanged_image) {
         copy_backup_image(vo, ctx->num_buffers, ctx->visible_buf);
-        ctx->have_visible_image_copy = true;
-    }
-    else
+        ctx->have_image_copy = true;
+    }  else
         return false;
-    int temp = ctx->current_buf;
     ctx->current_buf = ctx->visible_buf;
-    draw_osd(vo, osd);
-    ctx->current_buf = temp;
-    put_xvimage(vo, ctx->xvimage[ctx->visible_buf]);
     return true;
 }
 
@@ -478,11 +470,6 @@ static void flip_page(struct vo *vo)
     /* remember the currently visible buffer */
     ctx->visible_buf = ctx->current_buf;
 
-    ctx->have_visible_image_copy = ctx->have_next_image_copy;
-    ctx->have_next_image_copy = false;
-    ctx->unchanged_visible_image = ctx->unchanged_next_image;
-    ctx->unchanged_next_image = false;
-
     if (ctx->num_buffers > 1) {
         ctx->current_buf = vo_directrendering ? 0 : ((ctx->current_buf + 1) %
                                                      ctx->num_buffers);
@@ -525,11 +512,12 @@ static int draw_slice(struct vo *vo, uint8_t *image[], int stride[], int w,
     return 0;
 }
 
-static mp_image_t *get_screenshot(struct vo *vo) {
+static mp_image_t *get_screenshot(struct vo *vo)
+{
     struct xvctx *ctx = vo->priv;
 
     // try to get an image without OSD
-    if (ctx->have_visible_image_copy)
+    if (ctx->have_image_copy)
         copy_backup_image(vo, ctx->visible_buf, ctx->num_buffers);
 
     XvImage *xv_image = ctx->xvimage[ctx->visible_buf];
@@ -571,7 +559,7 @@ static uint32_t draw_image(struct vo *vo, mp_image_t *mpi)
 {
     struct xvctx *ctx = vo->priv;
 
-    ctx->have_next_image_copy = false;
+    ctx->have_image_copy = false;
 
     if (mpi->flags & MP_IMGFLAG_DIRECT)
         // direct rendering:
@@ -591,9 +579,9 @@ static uint32_t draw_image(struct vo *vo, mp_image_t *mpi)
 
     if (ctx->is_paused) {
         copy_backup_image(vo, ctx->num_buffers, ctx->current_buf);
-        ctx->have_next_image_copy = true;
+        ctx->have_image_copy = true;
     }
-    ctx->unchanged_next_image = true;
+    ctx->unchanged_image = true;
     return true;
 }
 
@@ -873,8 +861,8 @@ static int control(struct vo *vo, uint32_t request, void *data)
     case VOCTRL_UPDATE_SCREENINFO:
         update_xinerama_info(vo);
         return VO_TRUE;
-    case VOCTRL_REDRAW_OSD:
-        return redraw_osd(vo, data);
+    case VOCTRL_REDRAW_FRAME:
+        return redraw_frame(vo);
     case VOCTRL_SCREENSHOT: {
         struct voctrl_screenshot_args *args = data;
         args->out_image = get_screenshot(vo);