Curves are the building blocks of a model; they are the geometric lines that create your model. They can be straight lines between two points, or curves comprising three or more points.
Curves are assigned the identification label 'C'. Every curve has an unique identification, comprised of the letter C followed by a number. When you select curves, the identifiers are listed in the selection list.
The three types of curves are:
- Line - a straight line, defined by two end points or nodes
- Arc - a section of a circular curve, which is defined either by a center point, or an arc and angle, or three points on a plane.
- Spline - a cubic spline interpolation on a supplied set of points.
