Crate nbezier 

nbezier

nbezier aims to be a general purpose library for working with bezier curves of any degree.

It uses nalgebra (hence the name) to implement a generic BezierCurve.

This library also provides a non-generic type SimpleCurve hiding nalgebra’s complexity. SimpleCurve is optimised for cubic bezier curves while supporting arbitrary degree.

Current Features

• store curve as list of control points (a matrix’ column vector to be precise)
• de Castlejau’s Algorithm
  • evaluate a point
  • split a curve
• compute a curve’s polynomial and its derivative
  • normal and tangental vectors
• a curve’s control points’ axis aligned bounding box and convex hull
• raise or reduce a curve’s degree

Experimental Features

• find a point on a curve
• find all intersection points between two curves

Planned Features

• any suggestions?

How is SimpleCurve optimised?

Using nalgebra BezierCurve is generic over its degree. SimpleCurve is an enum storing curves of degree 1, 2, 3 and anything above in its 4 variants. Since these low degrees are their own variant with dedicated type, rust can monomorphize these computing a lot of “magical constants” at compile time. Also these degree’s variants are stored exclusively on the stack giving them an enormous performance boost.

Re-exports

pub use crate::nbezier::BezierCurve;

pub use crate::simple::SimpleCurve;

Modules

bounding_box

A simple geometry primitive

graham_scan

Implementation of Graham scan for constructing convex hulls.

nbezier

A wrapper around nalgebra::Matrix interpreting it as a bezier curve.

npolynomial

A wrapper around nalgebra::Matrix interpreting it as a polynomial.

simple

Wrapper for BezierCurve and Polynomial with simple interface