1 files changed, 9 insertions, 1 deletions
diff --git a/ui/vnc.h b/ui/vnc.h
index e63c14284b..8da81b8d6e 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -81,8 +81,16 @@ typedef void VncSendHextileTile(VncState *vs,
 #define VNC_MAX_WIDTH 2560
 #define VNC_MAX_HEIGHT 2048
 
+/* VNC_DIRTY_PIXELS_PER_BIT is the number of dirty pixels represented
+ * by one bit in the dirty bitmap */
+#define VNC_DIRTY_PIXELS_PER_BIT 16
+
 /* VNC_DIRTY_BITS is the number of bits in the dirty bitmap. */
-#define VNC_DIRTY_BITS (VNC_MAX_WIDTH / 16)
+#define VNC_DIRTY_BITS (VNC_MAX_WIDTH / VNC_DIRTY_PIXELS_PER_BIT)
+
+/* VNC_DIRTY_BPL (BPL = bits per line) might be greater than
+ * VNC_DIRTY_BITS due to alignment */
+#define VNC_DIRTY_BPL(x) (sizeof((x)->dirty) / VNC_MAX_HEIGHT * BITS_PER_BYTE)
 
 #define VNC_STAT_RECT  64
 #define VNC_STAT_COLS (VNC_MAX_WIDTH / VNC_STAT_RECT)