+/**
+ * Gets the maximum allowed height while generating a map based on
+ * mapsize, terraintype, and the maximum height level.
+ * @return The maximum height for the map generation.
+ */
+static height_t TGPGetMaxHeight()
+{
+	/**
+	 * Desired maximum height - indexed by:
+	 *  - _settings_game.difficulty.terrain_type
+	 *  - min(MapLogX(), MapLogY()) - MIN_MAP_SIZE_BITS
+	 *
+	 * It is indexed by map size as well as terrain type since the map size limits the height of
+	 * a usable mountain. For example, on a 64x64 map a 24 high single peak mountain (as if you
+	 * raised land 24 times in the center of the map) will leave only a ring of about 10 tiles
+	 * around the mountain to build on. On a 4096x4096 map it will just be a small annoyance that
+	 * you can easily build around; it's not really a mountain.
+	 */
+	static const int max_height_divisor[4][MAX_MAP_SIZE_BITS - MIN_MAP_SIZE_BITS + 1] = {
+		{21, 40, 50,  64, 128, 380,  760 }, ///< Very flat
+		{16, 27, 38,  51, 102, 204,  408 }, ///< Flat
+		{10, 13, 17,  20,  33,  66,  132 }, ///< Hilly
+		{9,  10, 11,  12,  13,  24,   48 }, ///< Mountainous
+	};
+
+	int divisor = max_height_divisor[_settings_game.difficulty.terrain_type][min(MapLogX(), MapLogY()) - MIN_MAP_SIZE_BITS];
+	int map_size_max_height = min(_height_map.size_x + 1, _height_map.size_y + 1) / divisor;
+	return I2H(min(map_size_max_height, _settings_game.construction.max_heightlevel));
+}