Fig. 4
From: From CAD to representations suitable for isogeometric analysis: a complete pipeline
Schematic of a cubic B-spline with knot vector [0, 0, 0, 0, 1, 2, 3, 4,...]. The slope control point is shown in red, and all other control points in blue. The location of the red point influences the shape of the spline only within the first two knot spans. (Color figure online)