From 77f730f63c340fc88e8c3db0cb73cff1807d7432 Mon Sep 17 00:00:00 2001
From: wm4 <wm4@nowhere>
Date: Fri, 22 May 2020 14:18:35 +0200
Subject: [PATCH] mp_image: add helper for clearing regions outside of a
 rectangle

Not sure if generally useful; the following commit uses it.
---
 video/mp_image.c | 14 ++++++++++++++
 video/mp_image.h |  2 ++
 2 files changed, 16 insertions(+)

diff --git a/video/mp_image.c b/video/mp_image.c
index 81d2b7e04f..0e95a59808 100644
--- a/video/mp_image.c
+++ b/video/mp_image.c
@@ -678,6 +678,20 @@ void mp_image_clear(struct mp_image *img, int x0, int y0, int x1, int y1)
     }
 }
 
+void mp_image_clear_rc(struct mp_image *mpi, struct mp_rect rc)
+{
+    mp_image_clear(mpi, rc.x0, rc.y0, rc.x1, rc.y1);
+}
+
+// Clear the are of the image _not_ covered by rc.
+void mp_image_clear_rc_inv(struct mp_image *mpi, struct mp_rect rc)
+{
+    struct mp_rect clr[4];
+    int cnt = mp_rect_subtract(&(struct mp_rect){0, 0, mpi->w, mpi->h}, &rc, clr);
+    for (int n = 0; n < cnt; n++)
+        mp_image_clear_rc(mpi, clr[n]);
+}
+
 void mp_image_vflip(struct mp_image *img)
 {
     for (int p = 0; p < img->num_planes; p++) {
diff --git a/video/mp_image.h b/video/mp_image.h
index 5b7eada496..dd82251464 100644
--- a/video/mp_image.h
+++ b/video/mp_image.h
@@ -137,6 +137,8 @@ void mp_image_setrefp(struct mp_image **p_img, struct mp_image *new_value);
 void mp_image_unrefp(struct mp_image **p_img);
 
 void mp_image_clear(struct mp_image *mpi, int x0, int y0, int x1, int y1);
+void mp_image_clear_rc(struct mp_image *mpi, struct mp_rect rc);
+void mp_image_clear_rc_inv(struct mp_image *mpi, struct mp_rect rc);
 void mp_image_crop(struct mp_image *img, int x0, int y0, int x1, int y1);
 void mp_image_crop_rc(struct mp_image *img, struct mp_rect rc);
 void mp_image_vflip(struct mp_image *img);