1 files changed, 1 insertions, 1 deletions

diff --git a/apps/plugins/lib/grey_draw.c b/apps/plugins/lib/grey_draw.c
index 7b24ba4c70..a1b99fc13b 100644
--- a/apps/plugins/lib/grey_draw.c
+++ b/apps/plugins/lib/grey_draw.c
@@ -630,7 +630,7 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
     {
 #if LCD_PIXELFORMAT == HORIZONTAL_PACKING
         int idx = _GREY_MULUQ(_grey_info.width, yc);
-#else
+#else /* vertical packing or vertical interleaved */
         int idx = _GREY_MULUQ(_grey_info.width, yc & ~_GREY_BMASK)
                 + (~yc & _GREY_BMASK);
 #endif /* LCD_PIXELFORMAT */