Abstract: Methods and apparatus for mapping a feature onto a simulated surface having contoured portions, the surface being definable by a plurality of generally adjacent triangulations, the surface being further definable by a plurality of intersecting isoparametric curves linking identified values of the feature to identified points on the surface. In one embodiment, the isoparametric curves are characterized in that when the surface is flat, the isoparametric curves intersect one another in a perpendicular manner, and the perpendicularity of the intersections on the contoured portions of the surface is maintained. In another embodiment, the isoparametric curves are characterized in that when the surface is flat. The isoparametric curves are spaced a predetermined distance apart, and the spacing of the intersections on the contoured portions of the surface is maintained.