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).

5 files changed, 40 insertions, 42 deletions

diff --git a/libvo/video_out.c b/libvo/video_out.c
index 82cf0dbbfe..0b1f7d1fab 100644
--- a/libvo/video_out.c
+++ b/libvo/video_out.c
@@ -285,6 +285,17 @@ int vo_draw_image(struct vo *vo, struct mp_image *mpi, double pts)
     return 0;
 }
 
+int vo_redraw_frame(struct vo *vo)
+{
+    if (!vo->config_ok)
+        return -1;
+    if (vo_control(vo, VOCTRL_REDRAW_FRAME, NULL) == true) {
+        vo->redrawing = true;
+        return 0;
+    }
+    return -1;
+}
+
 int vo_get_buffered_frame(struct vo *vo, bool eof)
 {
     if (!vo->config_ok)
@@ -339,8 +350,11 @@ void vo_flip_page(struct vo *vo, unsigned int pts_us, int duration)
 {
     if (!vo->config_ok)
         return;
-    vo->frame_loaded = false;
-    vo->next_pts = MP_NOPTS_VALUE;
+    if (!vo->redrawing) {
+        vo->frame_loaded = false;
+        vo->next_pts = MP_NOPTS_VALUE;
+    }
+    vo->redrawing = false;
     if (vo->driver->flip_page_timed)
         vo->driver->flip_page_timed(vo, pts_us, duration);
     else
@@ -486,6 +500,7 @@ int vo_config(struct vo *vo, uint32_t width, uint32_t height,
     }
     vo->frame_loaded = false;
     vo->waiting_mpi = NULL;
+    vo->redrawing = false;
     return ret;
 }
 
diff --git a/libvo/video_out.h b/libvo/video_out.h
index a710f7de4a..032a32b1cc 100644
--- a/libvo/video_out.h
+++ b/libvo/video_out.h
@@ -65,7 +65,7 @@ enum mp_voctrl {
 
     VOCTRL_NEWFRAME,
     VOCTRL_SKIPFRAME,
-    VOCTRL_REDRAW_OSD,
+    VOCTRL_REDRAW_FRAME,
 
     VOCTRL_ONTOP,
     VOCTRL_ROOTWIN,
@@ -263,6 +263,7 @@ struct vo {
     struct mp_image *waiting_mpi;
     double next_pts;    // pts value of the next frame if any
     double next_pts2;   // optional pts of frame after that
+    bool redrawing;     // between redrawing frame and flipping it
 
     double flip_queue_offset; // queue flip events at most this much in advance
 
@@ -306,6 +307,7 @@ void list_video_out(void);
 
 int vo_control(struct vo *vo, uint32_t request, void *data);
 int vo_draw_image(struct vo *vo, struct mp_image *mpi, double pts);
+int vo_redraw_frame(struct vo *vo);
 int vo_get_buffered_frame(struct vo *vo, bool eof);
 void vo_skip_frame(struct vo *vo);
 int vo_draw_frame(struct vo *vo, uint8_t *src[]);
diff --git a/libvo/vo_gl.c b/libvo/vo_gl.c
index b38a8d75e4..ec6e6573e6 100644
--- a/libvo/vo_gl.c
+++ b/libvo/vo_gl.c
@@ -1506,14 +1506,10 @@ static int control(struct vo *vo, uint32_t request, void *data)
             break;
         p->glctx->update_xinerama_info(vo);
         return VO_TRUE;
-    case VOCTRL_REDRAW_OSD:
+    case VOCTRL_REDRAW_FRAME:
         if (vo_doublebuffering)
             do_render(vo);
-        draw_osd(vo, data);
-        if (vo_doublebuffering)
-            do_render_osd(vo, 2);
-        flip_page(vo);
-        return VO_TRUE;
+        return true;
     case VOCTRL_SCREENSHOT: {
         struct voctrl_screenshot_args *args = data;
         if (args->full_window)
diff --git a/libvo/vo_vdpau.c b/libvo/vo_vdpau.c
index f087f6cf38..bb82b7613d 100644
--- a/libvo/vo_vdpau.c
+++ b/libvo/vo_vdpau.c
@@ -1872,11 +1872,8 @@ static int control(struct vo *vo, uint32_t request, void *data)
     case VOCTRL_SKIPFRAME:
         vc->deint_queue_pos = next_deint_queue_pos(vo, true);
         return true;
-    case VOCTRL_REDRAW_OSD:
+    case VOCTRL_REDRAW_FRAME:
         video_to_output_surface(vo);
-        draw_eosd(vo);
-        draw_osd(vo, data);
-        flip_page_timed(vo, 0, -1);
         return true;
     case VOCTRL_RESET:
         forget_frames(vo);
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);