is it possible with TikZ to align a new node with respect to existing ones? I know the answer is affirmative in the case of one node using e.g. the node coordinate system, but what about align with respect to two nodes?
Example: suppose there are two nodes defined (A) and (B) and I want to create a third node (C) such that xy-coordinates satisfy C.x = A.x and C.y = B.y i.e. node (C) is vertically aligned with (B) and horizontally aligned with (A).