Spline curves can be created in single-segment and multi-segment ways. For a single spline. Order = number of points-1, so a single spline can only use 25 points at most. The construction method of single segment has some limitations. The more points defined, the higher the order of the spline, and the higher the order, and the spline will have unexpected results such as deformation.
Moreover, single-segment splines cannot be closed, so it is not recommended to use single-segment splines. The order of a multi-segment spline is defined by the user (≤24), and the number of points defined by the spline is unlimited, but at least a little more than the order. In design, cubic spline is usually used.
Extended data
Order of surfaces:
The order of a surface is a mathematical concept, which is the highest order of a cubic polynomial equation that defines a surface. Users are advised to use cube surfaces as much as possible. If the level is too high, the calculation of the system will be too large, resulting in unexpected results, and it is easy to lose data during data exchange.
Creating boundary curves of surfaces is as simple as possible. Generally speaking, the order of a curve is not greater than 3. When curvature continuity is needed, a fifth-order curve can be considered.
Boundary curves used to create surfaces should be smooth and continuous to avoid sharp corners, intersections and overlaps. In addition, when creating a surface, it is necessary to analyze the curvature of the curve used, and the radius of curvature should be as large as possible, otherwise it will cause difficulties in machining and complicated shapes.
Baidu encyclopedia-spline
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