ECS 178 -- Geometric Modeling Unit 5 -- The B-Spline Curve B-Spline curves generalize Bézier Curves
 Home Video Lectures and Notes FAQs
 joy@cs.ucdavis.edu

# Unit 5 -- The B-spline Curve

Section Description Video Notes Exercises

## The B-Spline Curve

### The Geometric Definition of the B-spline Curve:

We define the geometric definition of the B-spline curve. This is clearly an extension of the geometric definition for the Bézier curve.

### A Bézier Curve is a B-Spline Curve:

What would be the knots for a Bézier curve?.

### The Analytic Definition of the B-spline Curve:

We can specify the blending functions in a recursive way, similar to the Bernstein polynomials for Bézier curves. Unfortunately, since B-splines are piecewise Bézier curves, these functions are somewhat messy.

### Thinking in Pyramids

It is useful to use a pyramid structure to visualize the B-spline algorithms.

### The DeBoor-Cox Calculation

We use the DeBoor-Cox calculation to show that the geometric and analytic definitions of B-spline curves are equivalent. This is an interesting computation, as the technique usually doesn't work in general. This time it does.

### Properties of B-Spline Curves:

Lots of properties for B-spline curves. They are similar to those for Bézier curves, but more complex because we are piecing things together.

### On Knots

Knots are slippery things.

### The Catmull-Rom Spline

A look at an interpolating spline for comparison.