ui/vnc: optimize full scanline updates

in case we send and update for a complete scanline increment
the y offset to avoid running to find_next_bit for that lines
twice.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/ui/vnc.c b/ui/vnc.c
index faa218f84b..14289fd951 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -1111,6 +1111,12 @@ static int vnc_update_client(VncState *vs, int has_dirty, bool sync)
                 n += vnc_job_add_rect(job, x * VNC_DIRTY_PIXELS_PER_BIT, y,
                                       (x2 - x) * VNC_DIRTY_PIXELS_PER_BIT, h);
             }
+            if (!x && x2 == width / VNC_DIRTY_PIXELS_PER_BIT) {
+                y += h;
+                if (y == height) {
+                    break;
+                }
+            }
         }
 
         vnc_job_push(job);