Syntax:
set cntrparam { { linear | cubicspline | bspline } |
points <n> |
levels <n> |
order <n> }
This command controls the way contours are plotted. <n> should be an integral constant expression. The parameters are:
linear, cubicspline, bspline - Controls type of approximation or interpolation. If linear, then the contours are drawn piecewise linear, as extracted from the surface directly. If cubicspline, then piecewise linear contours are interpolated to form a somewhat smoother contours, but which may undulate. The third option is the uniform bspline, which only approximates the piecewise linear data but is guaranteed to be smoother.
points - Eventually all drawings are done with piecewise linear strokes. This number controls the number of points used to approximate a curve. Relevant for cubicspline and bspline modes only.
levels - Number of contour levels. If the surface is bounded by zmin and zmax then contours will be generated from zmin+dz to zmax-dz in steps of size dz, where dz = (zmax - zmin) / (levels + 1).
order - Order of the bspline approximation to be used. The bigger this order is, the smoother the resulting contour. (Of course, higher order bspline curves will move further away from the original peicewise linear data.) This option is relevant for bspline mode only. Allowed values are integers in the range from 2 (linear) to 10.