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---+ bezier.js

Provides two mathematical functions for drawing Bezier curves.

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---++ Functions

---+++ OAT.Bezier.setPointList(pointList)

Marks an array of 2D points as a base for a Bezier curve.

---+++ OAT.Bezier.initFactorial(max)

Pre-computes factorials of <tt>1..max</tt> for later execution. Call this function once, in the initialization part of your script. This speeds up creation of bezier curves using <tt>OAT.Bezier.create2()</tt> function. Set the max argument to the number of points.

---+++ OAT.Bezier.create()

Returns a Bezier functionf: <tt>[0,1] -> R^2</tt> which describes parametric Bezier curve, based on points set by <tt>OAT.Bezier.setPointList()</tt>.

Uses slow but precise recursive [[http://en.wikipedia.org/wiki/De_Casteljau%27s_algorithm][de Casteljau's algorithm]].

---+++ OAT.Bezier.create2()

Returns a Bezier functionf: <tt>[0,1] -> R^2</tt> which describes parametric Bezier curve, based on points set by <tt>OAT.Bezier.setPointList()</tt>.

Uses faster factorial algorithm based directly on [[http://en.wikipedia.org/wiki/Bernstein_polynomial][Bernstein polynomials]].

---++ Example

<verbatim>
var points = [];
points.push([0,0]);
points.push([1,0]);
points.push([1,1]);
OAT.Bezier.setPointList(points);
var f = OAT.Bezier.create2();
alert(f(0.5)); // [x, y] where x in [0,1], y in [0,1]
</verbatim>

CategoryDocumentation CategoryOAT CategoryOpenSource