From f31ddf7fe9f9b4c98e90c147722b1da11fb24e52 Mon Sep 17 00:00:00 2001
From: Andri Yngvason <andri@yngvason.is>
Date: Sat, 5 Nov 2022 13:52:55 +0000
Subject: [PATCH] enc-util: Add function to calculate region area

---
 include/enc-util.h |  4 +++-
 src/enc-util.c     | 21 ++++++++++++++++++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/include/enc-util.h b/include/enc-util.h
index 6f3abac..3844c32 100644
--- a/include/enc-util.h
+++ b/include/enc-util.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 - 2020 Andri Yngvason
+ * Copyright (c) 2019 - 2022 Andri Yngvason
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -21,7 +21,9 @@
 #include <stdint.h>
 
 struct vec;
+struct pixman_region16;
 
 int encode_rect_head(struct vec* dst, enum rfb_encodings encoding,
 		uint32_t x, uint32_t y, uint32_t width, uint32_t height);
 uint32_t calc_bytes_per_cpixel(const struct rfb_pixel_format* fmt);
+uint32_t calculate_region_area(struct pixman_region16* region);
diff --git a/src/enc-util.c b/src/enc-util.c
index 4845940..4e74d92 100644
--- a/src/enc-util.c
+++ b/src/enc-util.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 - 2020 Andri Yngvason
+ * Copyright (c) 2019 - 2022 Andri Yngvason
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -19,6 +19,8 @@
 #include "vec.h"
 
 #include <arpa/inet.h>
+#include <stdint.h>
+#include <pixman.h>
 
 #define UDIV_UP(a, b) (((a) + (b) - 1) / (b))
 
@@ -41,3 +43,20 @@ uint32_t calc_bytes_per_cpixel(const struct rfb_pixel_format* fmt)
 	return fmt->bits_per_pixel == 32 ? UDIV_UP(fmt->depth, 8)
 	                                 : UDIV_UP(fmt->bits_per_pixel, 8);
 }
+
+uint32_t calculate_region_area(struct pixman_region16* region)
+{
+	uint32_t area = 0;
+
+	int n_rects = 0;
+	struct pixman_box16* rects = pixman_region_rectangles(region,
+		&n_rects);
+
+	for (int i = 0; i < n_rects; ++i) {
+		int width = rects[i].x2 - rects[i].x1;
+		int height = rects[i].y2 - rects[i].y1;
+		area += width * height;
+	}
+
+	return area;
+}