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  • Bezier - A Bezier basis generates a 3D curve that passes through every third control vertex. The remaining control vertex positions are used to determine the incoming and outgoing tangent of the curve of the adjacent vertex that the curve does pass through. When using a Bezier basis with curves that contain multiple segments (that is, more than 4 control points), some care should be taken to ensure that incoming and outcoming tangents line up at vertices that are on the rendered curve, or there will be a discontinuity in the smoothness of the curve where it suddenly changes direction.
  • B-Spline - While a B-Spline basis function can be somewhat less intuitive to use in that it generates a curve that typically only approximately comes close to passing through the given control vertices, an advantage is that this basis function tends to yield very smooth curves. Discontinuities in the smoothness of the curve are possible if multiple control vertices are repeated consecutively.
  • Catmull-Rom - This basis function generates a curve that is guaranteed to pass through every interior, non-endpoint control vertex, and it tends to generate smooth curves, although there can sometimes be unexpected "wobbles" in areas of high curvature with this basis function choice (see images below for an example). Using a B-Spline basis instead can smooth out the wobbles, although a B-Spline basis typically produces a curve that does not pass through the control vertices exactly, unlike the Catmull-Rom basis (for non-endpoint control vertices).
  • Hermite - The Hermite basis function generates a curve that passes through every other control vertex; the remaining control "vertices" are actually vectors that determine the tangent of the curve. The length of the tangent vectors determines the amount of curvature; longer tangent vectors yield more curvature along the spline than shorter vectors. A Hermite basis function tends to produce smooth curves, although using a B-Spline basis can often yield qualitatively a more "natural" or uniform smoothness along the curve with comparatively less specification effort.
  • Linear - Specifying linear curves yields straight line segments, continuous linear segments in a curve are joined with a round cap.

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