The left side of the figure shows the surface of a half-cylinder, with its axis oriented horizontally. On the surface, the constant N lines are axial, and the constant M lines are circumferential. A "diagonal" line is drawn on the cylinder's surface.

The right side of the figure shows the same half-cylinder, with two new surfaces drawn on its surface. One extends to the bottom, from the original diagonal line, to the six o'clock position of the cylinder. The other extends to the top, from the original diagonal line, to the twelve o'clock position of the cylinder.

In the new surfaces, the "circumferential" grid lines are at the same "axial" locations as the points of the original diagonal line. The "axial" grid lines in the new surfaces are equally spaced in the circumferential direction.


Last updated 2 Apr 2003