From 79e5bb758d61785759395857d8401899e8503bd4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Janiszewski?= <janisozaur@gmail.com>
Date: Sat, 26 Dec 2015 13:12:45 +0100
Subject: [PATCH] Add an assert for getting proper mapElementType

---
 src/windows/map.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/windows/map.c b/src/windows/map.c
index b6d004249e..9c244c0cb4 100644
--- a/src/windows/map.c
+++ b/src/windows/map.c
@@ -1546,9 +1546,10 @@ static uint16 map_window_get_pixel_colour_peep(int x, int y)
 		colour = 10 | (colour & 0xFF00);
 
 	while (!map_element_is_last_for_tile(mapElement++)) {
-		int mapElementType = map_element_get_type(mapElement);
-		colour &= ElementTypeMaskColour[mapElementType >> 2];
-		colour |= ElementTypeAddColour[mapElementType >> 2];
+		int mapElementType = map_element_get_type(mapElement) >> 2;
+		assert(mapElementType < countof(ElementTypeMaskColour));
+		colour &= ElementTypeMaskColour[mapElementType];
+		colour |= ElementTypeAddColour[mapElementType];
 	}
 
 	return colour;