/ point-geometry Public

A standalone point geometry primitive.

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# mapbox/point-geometry

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# @mapbox/point-geometry

A `Point` class for representing point geometry with useful utility methods.

## Installation

`\$ npm install @mapbox/point-geometry`

## API

### 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 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
• `a` number angle to rotate around, in radians
• `p` Point Point to rotate around

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
• `x` number the x-coordinate
• `y` number the y-coordinate

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

##### 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.

A standalone point geometry primitive.

v1.0.0 Latest
Jul 11, 2024