1461185758-2bc6ad02-86cd-4e13-9b60-92e4669e0189

A step for ingress and egress from a swimming pool andor a spa includes a tread including opposing side edges, a riser coupled with and extending substantially perpendicular from one of the side edges of the tread and an upper flange substantially perpendicular to said tread and coupled with and extending upwardly or downwardly from one of the opposing side edges of the tread opposite the riser. The resin is typically polyurethane, which may be foamed or unfoamed. The slope compensation signal is generated based on the upslope signal and a difference between an input voltage and an output voltage of the current-mode switching regulator. Furthermore, when an edge slope is computed for a vertex with a w coordinate equal to zero, the slope is set equal to the vertex in device coordinate space rather than the difference of the two vertices defining the edge.