Isosamples

The isoline density of surfaces may be changed by the set isosamples command.

Syntax:

        set isosamples <iso_1> {,<iso_2>}
        show isosamples

Each surface plot will have <iso_1> iso-u lines and <iso_2> iso-v lines. If you only specify <iso_1>, <iso_2> will be set to the same value as <iso_1>. By default, sampling is set to 10 isolines per u or v axis. A higher sampling rate will produce more accurate plots, but will take longer. These parameters have no effect on data file plotting.

An isoline is a curve parameterized by one of the surface parameters while the other surface parameter is fixed. Isolines provide a simple means to display a surface. By fixing the u parameter of surface s(u,v), the iso-u lines of the form c(v) = s(u0,v) are produced, and by fixing the v parameter, the iso-v lines of the form c(u) = s(u,v0) are produced.

When a surface plot is being done without the removal of hidden lines, set samples also has an effect on the number of points being evaluated—it controls the number of points sampled along each isoline. See set samples.