α = Conic Generator Angle
Xv = X Coordinate Value, Conic Vertex
Yv = Y Coordinate Value, Conic Vertex
Xs = X Coordinate Value, Surface Data
Ys = Y Coordinate Value, Surface Data
Zs = Z Coordinate Value, Surface Data
Zs = (1 / tan α) ((Xs – Xv)2 + (Ys – Yv)2) .5
