Quartic curves

A quartic Bézier curve has five control points and degree four. Use it when the source data already has five points and reducing it to a cubic curve would change the path.

Create a curve

<?php

require __DIR__.'/vendor/autoload.php';

use Alto\Bezier\Point;
use Alto\Bezier\QuarticCurve;

$curve = new QuarticCurve(
    new Point(10, 170),
    new Point(60, 10),
    new Point(120, 190),
    new Point(180, 20),
    new Point(230, 170),
);

echo $curve->pointAt(0.5).PHP_EOL;

The midpoint is:

(120, 100)

The public properties p0 through p4 retain the original points. SVG has no native quartic path command, so renderers must sample the curve or convert it to supported segments.

See Operations for sampling the curve with points().