nessworthy / decasteljau
A stupid way of using De Casteljau's algorithm to calculate control points of a segment in a cubic bezier curve.
1.0.0
2018-07-18 09:25 UTC
Requires (Dev)
- phpunit/phpunit: ^7.2
This package is auto-updated.
Last update: 2024-10-18 06:26:30 UTC
README
A stupid way of using De Casteljau's algorithm to calculate control points of a segment in a cubic bezier curve in PHP.
I used this a fair amount when trying to work out segments for SVG paths.
Requirements
- PHP 7
Installation
composer require nessworthy/decasteljau
Usage
The algorithm requires 6 pieces of information - the original 4 control points of your bezier curve, where you want to cut your segment, and how long you want your segment to be.
Example:
<?php use Nessworthy\DeCasteljau\CubicBezierCurve; use Nessworthy\DeCasteljau\Point; $curve = new CubicBezierCurve( new Point(0, 0), // Your start point. new Point(75, 0), // The first curve point. new Point(150, 75), // The second curve point. new Point(150, 150) // Your finishing point. ); // Calculate control points for the third quarter of the original curve. $curveSegment = $curve->getSegment(0.5, 0.75); // Instance of CubicBezierCurve // Useful for calculating SVG bezier paths! echo 'M' . $curveSegment->getControlPoint1()->x() . ' ' . $curveSegment->getControlPoint1()->y(); echo ' C' . $curveSegment->getControlPoint2()->x() . ' ' . $curveSegment->getControlPoint2()->y(); echo ', ' . $curveSegment->getControlPoint3()->x() . ' ' . $curveSegment->getControlPoint3()->y(); echo ', ' . $curveSegment->getControlPoint4()->x() . ' ' . $curveSegment->getControlPoint4()->y();
License
WTFPL - See LICENSE.md