Of course there is. Compute the determinant of the orientation vector of the runways and the vector from one runway centre to another, the result will be positive or negative depending on which runway are to the right of the other.
Calculation of determinant for a pair of 2D vectors:
Det(A,B) = Ax*By - Ay*Bx There is a load of other stuff one can learn about the use of determinants, but for this purpose it's all you need to know.
Edit, same thing in different words:
Compute the dot product of the orientation vector of the runways and the tværvector of the vector from one runway centre to another, the result will be positive or negative depending on which runway are to the right of the other.
DotProduct(A,B) = Ax*Bx + Ay*By A tværvector is the rotation of a 2D vector 90 degrees counter-clockwise. The tværvector T of A is calculated as follow:
Tx = -Ay Ty = Ax Edit, I guess I should try to explain why this works.
The result of a dot product is equal to the product of the length of the two vectors, by the cosine of the angle between them. Since lengths are always positive and cosine is positive for angles in the range ]-90 deg; 90 deg[ the dot product is positive for acute angles, and negative for obtuse angles.
Imagine two parallel lines and a vector from any point on line 1 to any point on line 2, this vector may point in any direction within a 180 degrees arc, except from the two extremes. If we rotate this vector 90 degrees we also rotate the arc 90 degrees. This rotated arc is positioned exactly so that a vector parallel to the lines will either have an acute angle to all vectors within the arc, or an obtuse angle to all of them, depending on the position of the lines and the direction of the vector. Since the dot product works as an acute/obtuse test it can be used to tell whether a line is to the right of left of another, depending on which direction you look at them.