API Reference > geometry-core > Bspline Bspline A bspline curve or surface is used for curved freeform geometry defined by controls points (sometimes called poles). BSplineCurve -- a curve in XYZ coordinates BSplineSurfaceXYZ -- a surface with XYZ BsplineSurfaceXYZW -- a surface with weighted (rational) XYZ coordinates KnotVector -- vector of breakpoints in bspline definitions. Classes Name Description Bezier1dNd Shared implementation details for derived bezier curve classes BezierCurve3d 3d Bezier curve class. BezierCurve3dH 3d curve with homogeneous weights. BezierCurveBase Base class for CurvePrimitive (necessarily 3D) with _polygon. BSpline1dNd Bspline knots and poles for 1d-to-Nd. BSpline2dNd Bspline knots and poles for 2d-to-Nd. BSplineCurve3d A BSplineCurve3d is a bspline curve whose poles are Point3d. BSplineCurve3dBase Base class for BSplineCurve3d and BSplineCurve3dH. BSplineCurve3dH Weighted (Homogeneous) BSplineCurve in 3d BSplineSurface3d BSplineSurface3d is a parametric surface in xyz space. BSplineSurface3dH BsplinceCurve in xyzw homogeneous space KnotVector Array of non-decreasing numbers acting as a knot array for bsplines. Enumerations Name Description BSplineWrapMode Enumeration of the possible ways of converting a "periodic" knot vector to an open knot vector. UVSelect UVSelect is an integer indicating uDirection (0) or vDirection (1) in a bspline surface parameterization. WeightStyle Enumeration of how weights are carried Interfaces Name Description BSplineSurface3dQuery Interface for methods supported by both regular (xyz) and weighted (xyzw) bspline surfaces. PackedPointGrid interface for points returned from getPointGrid, with annotation of physical and weighting dimensions. Last Updated: 13 June, 2024