Experiment
For the same 4 control points, draw following curves.
1. cubic B-spline curve
2. Beta spline with skew (s) = 1.0 and tension (t) = 0.0. 3. Beta spline with skew (s) = 1.0 and tension (t) = 10.0. 4. Beta spline with skew (s) = 1.0 and tension (t) = 100.0. 5. Beta spline with skew (s) = 2.0 and tension (t) = 0.0.
Observation
1) Curve 1 and 2 are the same which is expected because when s = 1 and t = 0, their evaluation formulae are the same.
2) Curve 3 is straighter than curve 2 and curve 4 is straighter than curve 3. Actually, the curve 4 becomes straight line between two consecutive points. Because when tension becomes large,
the spline tends to approximate piece-wise linear function.
3) Curve 5 is skewer than curve 2. So increase skew s, we can make curve skewer.