A numerical approach is proposed to establish a new procedure for the visioplasticity method. In this procedure, finite flow-line regions are produced by the least-squares method first, and then the velocity and strain-rate field are obtained for each region. From the calculated strain-rate field, a new constructed model of the slip-line can then be developed to draw the slip-line field. Along these slip lines, the stress fields are found easily from Hencky's equations. Plane-strain extrusion through a cosine-curved die with 2:1 extrusion ratio is illustrated for this new procedure. The computed results for the velocity, effective-strain and stress fields are compared with the frictionless flow pattern, the slip-line of frictionless flow constructed from this procedure showing good agreement with those from Samanta's method.