Circle.js

Circle.js is a collection of functions to work with circles. The aim is to have a fast and correct library, which makes it easy to calculate the intersection of circles, the area of a circle and so on.

Every circle is defined by a cartesian point (x, y) and the radius r.

Circles.js is analogous to Rectangles.js and Angles.js.

const circle = require('circle.js');

const A = {x: 20, y: 20, r: 10};
const B = {x: 80, y: 80, r: 30};

if (circle.intersect(A, B)) {
  console.log(circle.intersection(A, B)); // Intersection points
  console.log(circle.intersectionArea(A, B)); // Intersection area
} else {
  console.log("no intersection");
}

Determines if two circles intersect

Calculates the intersection points of two circles

Calculates the intersection area of two circles

Calculates the area of a circle

Calculates the height of a circle. Obviously, this is the same as the width.

Calculates the width of a circle. Obviously, this is the same as the height.

Calculates the perimeter of a circle

Calculates the center point of a circle. Simply it's coordinates.

Resizes the circle by a given value on the center

Caclulates a circle {x, y, r} with given three {x, y} points

Installing Circle.js is as easy as cloning this repo or use one of the following command:

npm install circle.js

<script src="circle.min.js"></script>
<script>
console.log(Circle.center(A));
</script>

As every library I publish, Circle.js is also built to be as small as possible after compressing it with Google Closure Compiler in advanced mode. Thus the coding style orientates a little on maxing-out the compression rate. Please make sure you keep this style if you plan to extend the library.

After cloning the Git repository run:

npm install
npm run build

Testing the source against the shipped test suite is as easy as

npm run test

Copyright (c) 2024, Robert Eisele Licensed under the MIT license.