public boolean clearPathInRankBetween(Field from, Field to) { // Is vertically path between fields clear?
		for (char file='a'; file<='h'; file++) {
			if (this.fileBetween(file, from.file, to.file) && this.getField(file, from.rank).hasPiece()) {
				return false;
			}
		}
		return true;
	}