Converting binary decision diagram to truth table

Given a binary decision diagram, how do I convert it into a truth table? What is the exact algorithm for it ? I have been trying this for a long time. Here is an example which one can follow:

Source: Wikipedia.

(The dotted edges represent 0; solid edges, 1.)

Beginning at the root node, traverse tree in depth-first manner.

For each leaf node reached, record an entry in truth table as follows:

• x1 is 0 if you descended the dashed edge from node x1; 1 otherwise.
• x2 is 0 if you descended the dashed edge from node x2; 1 otherwise.
• x3 is 0 if you descended the dashed edge from node x3; 1 otherwise.
• f is value of the leaf node.