jsBezier 0.5

A collection JavaScript helper functions to deal with Bezier curves
Used mainly in jsPlub, they where built to be utilized with Bezier curves of arbitrary degree.

Main features:

  • Function List:
  • distanceFromCurve(point, curve) -- Calculates the distance that the given point lies from the given Bezier. Note that it is computed relative to the center of the Bezier, so if you have stroked the curve with a wide pen you may wish to take that into account! The distance returned is relative to the values of the curve and the point - it will most likely be pixels.
  • gradientAtPoint(curve, location) -- Calculates the gradient to the curve at the given location, as a decimal between 0 and 1 inclusive.
  • nearestPointOnCurve(point, curve) -- Calculates the nearest point to the given point on the given curve. The return value of this is a JS object literal, containing both the point's coordinates and also the location of the point (see above), for example: { point:{x:551,y:150}, location:0.263365 }.
  • pointOnCurve(curve, location) -- Calculates the coordinates of the point on the given Bezier curve at the given location.
  • pointAlongCurveFrom(curve, location, distance) -- Calculates the coordinates of the point on the given curve that is distance units from location. distance should be in the same coordinate space as that used to construct the Bezier curve. For an HTML Canvas usage, for example, distance would be a measure of pixels.
  • perpendicularToCurveAt(curve, location, length, distance) -- Calculates the perpendicular to the given curve at the given location. length is the length of the line you wish for (it will be centered on the point at location). distance is optional, and allows you to specify a point along the path from the given location as the center of the perpendicular returned. The return value of this is an array of two points: [ {x:...,y:...}, {x:...,y:...} ].

last updated on:
February 1st, 2013, 15:04 GMT
developed by:
Simon Porritt
license type:
MIT License
operating system(s):
Windows / Linux / Mac OS / BSD / Solaris
C: \ Graphics and Multimedia \ Graphics and Animations


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What's New in version 0.2
  • First release version of jsBezier.
read full changelog

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