Function MakeWetlands

src/landscape.cpp:1097–1126

* Make wetlands around the given tile. * @param centre The starting tile. * @param height The height of the wetlands. * @param river_length The length of the river. */

 * @param river_length The length of the river.
 */
static void MakeWetlands(TileIndex centre, uint height, uint river_length)
{
	MakeRiverAndModifyDesertZoneAround(centre);

	uint diameter = std::max((river_length), 16u);

	/* Some wetlands have trees planted among the water tiles. */
	bool has_trees = Chance16(1, 2);

	/* Create the main wetland area. */
	for (TileIndex tile : SpiralTileSequence(centre, diameter)) {
		if (!IsValidRiverTerminusTile(tile, height)) continue;

		/* Don't make a perfect square, but a circle with a noisy border. */
		uint radius = diameter / 2;
		if ((DistanceSquare(tile, centre) > radius * radius) && Chance16(3, 4)) continue;

		if (Chance16(1, 3)) {
			/* This tile is water. */
			MakeRiverAndModifyDesertZoneAround(tile);
		} else if (IsTileType(tile, MP_CLEAR)) {
			/* This tile is ground, which we always make rough. */
			SetClearGroundDensity(tile, CLEAR_ROUGH, 3);
			/* Maybe place trees? */
			if (has_trees && _settings_game.game_creation.tree_placer != TP_NONE) {
				PlaceTree(tile, Random(), true);
			}
		}
	}
}

/**
 * Try to end a river at a tile which is not the sea.