From cc1eee5beebf88ade11288fa99cb7db788109abd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=CE=B6eh=20Matt?= <5415177+ZehMatt@users.noreply.github.com>
Date: Sat, 6 May 2023 02:31:46 +0300
Subject: [PATCH] Fix #20134: Don't update grass length outside of the actual
 map

---
 src/openrct2/world/Map.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/openrct2/world/Map.cpp b/src/openrct2/world/Map.cpp
index ff4f7604be..315dae62f0 100644
--- a/src/openrct2/world/Map.cpp
+++ b/src/openrct2/world/Map.cpp
@@ -1335,6 +1335,9 @@ void MapUpdateTiles()
             for (int32_t blockX = 0; blockX < gMapSize.x; blockX += 256)
             {
                 auto mapPos = TileCoordsXY{ blockX + x, blockY + y }.ToCoordsXY();
+                if (MapIsEdge(mapPos))
+                    continue;
+
                 auto* surfaceElement = MapGetSurfaceElementAt(mapPos);
                 if (surfaceElement != nullptr)
                 {