Awesome
@mapbox/point-geometry
A Point
class for representing point geometry with useful utility methods.
Installation
$ npm install @mapbox/point-geometry
API
<!-- Generated by documentation.js. Update this documentation by updating the source code. -->Point
A standalone point geometry with useful accessor, comparison, and modification methods.
Parameters
x
number the x-coordinate. This could be longitude or screen pixels, or any other sort of unit.y
number the y-coordinate. This could be latitude or screen pixels, or any other sort of unit.
Examples
const point = new Point(-77, 38);
clone
Clone this point, returning a new point that can be modified without affecting the old one.
Returns Point the clone
add
Add this point's x & y coordinates to another point, yielding a new point.
Parameters
p
Point the other point
Returns Point output point
sub
Subtract this point's x & y coordinates to from point, yielding a new point.
Parameters
p
Point the other point
Returns Point output point
multByPoint
Multiply this point's x & y coordinates by point, yielding a new point.
Parameters
p
Point the other point
Returns Point output point
divByPoint
Divide this point's x & y coordinates by point, yielding a new point.
Parameters
p
Point the other point
Returns Point output point
mult
Multiply this point's x & y coordinates by a factor, yielding a new point.
Parameters
k
number factor
Returns Point output point
div
Divide this point's x & y coordinates by a factor, yielding a new point.
Parameters
k
number factor
Returns Point output point
rotate
Rotate this point around the 0, 0 origin by an angle a, given in radians
Parameters
a
number angle to rotate around, in radians
Returns Point output point
rotateAround
Rotate this point around p point by an angle a, given in radians
Parameters
Returns Point output point
matMult
Multiply this point by a 4x1 transformation matrix
Parameters
Returns Point output point
unit
Calculate this point but as a unit vector from 0, 0, meaning that the distance from the resulting point to the 0, 0 coordinate will be equal to 1 and the angle from the resulting point to the 0, 0 coordinate will be the same as before.
Returns Point unit vector point
perp
Compute a perpendicular point, where the new y coordinate is the old x coordinate and the new x coordinate is the old y coordinate multiplied by -1
Returns Point perpendicular point
round
Return a version of this point with the x & y coordinates rounded to integers.
Returns Point rounded point
mag
Return the magnitude of this point: this is the Euclidean distance from the 0, 0 coordinate to this point's x and y coordinates.
Returns number magnitude
equals
Judge whether this point is equal to another point, returning true or false.
Parameters
other
Point the other point
Returns boolean whether the points are equal
dist
Calculate the distance from this point to another point
Parameters
p
Point the other point
Returns number distance
distSqr
Calculate the distance from this point to another point, without the square root step. Useful if you're comparing relative distances.
Parameters
p
Point the other point
Returns number distance
angle
Get the angle from the 0, 0 coordinate to this point, in radians coordinates.
Returns number angle
angleTo
Get the angle from this point to another point, in radians
Parameters
b
Point the other point
Returns number angle
angleWith
Get the angle between this point and another point, in radians
Parameters
b
Point the other point
Returns number angle
angleWithSep
Find the angle of the two vectors, solving the formula for the cross product a x b = |a||b|sin(θ) for θ.
Parameters
Returns number the angle in radians
convert
Construct a point from an array if necessary, otherwise if the input is already a Point, or an unknown type, return it unchanged
Parameters
Examples
// this
var point = Point.convert([0, 1]);
// is equivalent to
var point = new Point(0, 1);
Returns Point constructed point, or passed-through value.