Point Calculation

A simple library that provides functions for cartesian point calculations.

Install

Install the package

npm i point-calculation

Import the module

var pc = require('point-calculation');

Supported Calculations

Many calculation use a simple class of Point. The structure of this class is as follows:

{
    x: number,
    y: number
}

Distance

Finds the distance between two points

distance(point1, point2);

Params

• point1: required Point
• point2: required Point

var pc = require('point-calculation');
var dist = pc.distance({x: 2, y: 2}, {x: 2, y: 4});
console.log(dist); // 2

Angle

Finds the angle of the line that passes through both of the points. Angle is returned in Radians.

angle(point1, point2);

Params

• point1: required Point
• point2: required Point

var pc = require('point-calculation');
var angle = pc.angle({x: 30, y: 37}, {x: 79, y: -51});
console.log(angle); // ~2.08

Rotate Point

Rotates a point around another point by a given angle.

rotatePoint(rotatingPoint, centerPoint, angle);

Params

• rotatingPoint: required Point This is where the point is before it is rotated.
• centerPoint: required Point The rotatingPoint is rotated around this point
• angle required angle in radians

var pc = require('point-calculation');
var point = pc.rotatePoint({x: 5, y: 0}, {x: 0, y: 0}, Math.PI / 6);
console.log(point); // {x: 4, y: -2}

Translate Point

Moves point a given distance and angle;

translatePoint(point, distance, angle);

Params

• point: required Point
• distance: required number
• angle: optional angle in radians (defaults to 0)

var pc = require('point-calculation');
var point = pc.translatePoint({x: 0, y: 0}, 5, Math.PI / 4);
console.log(point); // ~{x: 3.535, y: 3.535}

Find Point on Line

Returns a point between to points as a given distance

findPointOnLine(startPoint, endPoint, distanceFromStart)

Params

• startPoint: required Point
• endPoint: required Point
• distanceFromStart: required number

var pc = require('point-calculation');
var point = pc.findPointOnLine({x: 0, y: 0}, {x: 3, y: 4}, 3);
console.log(point); // ~{x: 1.8, y: 2.4}