syrupMatt's Journal: Movement Mathematics

Defining math equations to create movement in a matrix is harder than it looks. If you have a square matrix which is numbered sequentially from the first position from 1 to 81, how do you define a diagnol (or similar single line) path to go from point A in the matrix to point B?

Tried using a "touch" based formula which defines the values in an ever increasing square from the origin and the destination until a common point is found, which is then used as the first point in the line.

why do i have a feeling this isn't going to work?