/* Create additional river tiles around possible lock locations to connect them. */
	for (uint tile = 0; tile != MapSize(); tile++) {
		if (IsValidTile(tile) && IsTileType(tile, MP_WATER) && IsRiver(tile) && IsInclinedSlope(GetTileSlope(tile))) {

			Slope slope = GetTileSlope(tile);
			DiagDirection dir = GetInclinedSlopeDirection(slope);
			int delta_side = TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90RIGHT));
			int delta_mid = TileOffsByDiagDir(dir);

			// Partial example, for the first 3 tiles:

			int delta_counts[] = {2, 1, 1};
			int side_counts[] = {0, 1, -1};

			for (int m = -1; m <= 1; m += 2) {
				for (int i = 0; i < lengthof(delta_counts); i++) {
					TileIndex tc = tile + delta_counts[i] * delta_mid + m * delta_side * side_counts[i];
					// Process tile.
					if (side_counts[i] != 0) {
						if (IsWaterTile(tc)) {
							TileIndex tr = tc + delta_mid;
							if (!IsWaterTile(tr) && IsTileFlat(tr)) {
								MakeRiver(tr, Random());
								/* Remove desert directly around the river tile. */
								CircularTileSearch(&tr, 5, RiverModifyDesertZone, NULL);
							}
						}
					} else {
						if (!IsWaterTile(tc)) {
							MakeRiver(tc, Random());
							/* Remove desert directly around the river tile. */
							CircularTileSearch(&tc, 5, RiverModifyDesertZone, NULL);
						}
					}
				}
			}
		}
	}