# Class: Triangle

## Phaser.Geom. Triangle

A triangle is a plane created by connecting three points. The first two arguments specify the first point, the middle two arguments specify the second point, and the last two arguments specify the third point.

#### new Triangle( [x1] [, y1] [, x2] [, y2] [, x3] [, y3])

##### Parameters:
Name Type Argument Default Description
`x1` number <optional>
0

`x` coordinate of the first point.

`y1` number <optional>
0

`y` coordinate of the first point.

`x2` number <optional>
0

`x` coordinate of the second point.

`y2` number <optional>
0

`y` coordinate of the second point.

`x3` number <optional>
0

`x` coordinate of the third point.

`y3` number <optional>
0

`y` coordinate of the third point.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 15)

### Members

#### bottom :number

Bottom most Y coordinate of the triangle. Setting it moves the triangle on the Y axis accordingly.

##### Type:
• number
Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 401)

#### left :number

Left most X coordinate of the triangle. Setting it moves the triangle on the X axis accordingly.

##### Type:
• number
Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 287)

Right most X coordinate of the triangle. Setting it moves the triangle on the X axis accordingly.

##### Type:
• number
Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 325)

#### top :number

Top most Y coordinate of the triangle. Setting it moves the triangle on the Y axis accordingly.

##### Type:
• number
Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 363)

#### <readonly> type :integer

The geometry constant type of this object: `GEOM_CONST.TRIANGLE`. Used for fast type comparisons.

##### Type:
• integer
Since: 3.19.0
Source: src/geom/triangle/Triangle.js (Line 46)

#### x1 :number

`x` coordinate of the first point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 57)

#### x2 :number

`x` coordinate of the second point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 77)

#### x3 :number

`x` coordinate of the third point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 97)

#### y1 :number

`y` coordinate of the first point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 67)

#### y2 :number

`y` coordinate of the second point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 87)

#### y3 :number

`y` coordinate of the third point.

##### Type:
• number
Since: 3.0.0
Default Value:
• 0
Source: src/geom/triangle/Triangle.js (Line 107)

### Methods

#### <static> Area(triangle)

Returns the area of a Triangle.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to use.

Since: 3.0.0
Source: src/geom/triangle/Area.js (Line 9)
##### Returns:

The area of the Triangle, always non-negative.

Type
number

#### <static> BuildEquilateral(x, y, length)

Builds an equilateral triangle. In the equilateral triangle, all the sides are the same length (congruent) and all the angles are the same size (congruent). The x/y specifies the top-middle of the triangle (x1/y1) and length is the length of each side.

##### Parameters:
Name Type Description
`x` number

x coordinate of the top point of the triangle.

`y` number

y coordinate of the top point of the triangle.

`length` number

Length of each side of the triangle.

Since: 3.0.0
Source: src/geom/triangle/BuildEquilateral.js (Line 9)
##### Returns:

The Triangle object of the given size.

Type
Phaser.Geom.Triangle

#### <static> BuildFromPolygon(data [, holes] [, scaleX] [, scaleY] [, out])

Takes an array of vertex coordinates, and optionally an array of hole indices, then returns an array of Triangle instances, where the given vertices have been decomposed into a series of triangles.

##### Parameters:
Name Type Argument Default Description
`data` array

A flat array of vertex coordinates like [x0,y0, x1,y1, x2,y2, ...]

`holes` array <optional>
null

An array of hole indices if any (e.g. [5, 8] for a 12-vertex input would mean one hole with vertices 5–7 and another with 8–11).

`scaleX` number <optional>
1

Horizontal scale factor to multiply the resulting points by.

`scaleY` number <optional>
1

Vertical scale factor to multiply the resulting points by.

`out` array | Array.<Phaser.Geom.Triangle> <optional>

An array to store the resulting Triangle instances in. If not provided, a new array is created.

Since: 3.0.0
Source: src/geom/triangle/BuildFromPolygon.js (Line 10)
##### Returns:

An array of Triangle instances, where each triangle is based on the decomposed vertices data.

Type
array | Array.<Phaser.Geom.Triangle>

#### <static> BuildRight(x, y, width, height)

Builds a right triangle, i.e. one which has a 90-degree angle and two acute angles.

##### Parameters:
Name Type Description
`x` number

The X coordinate of the right angle, which will also be the first X coordinate of the constructed Triangle.

`y` number

The Y coordinate of the right angle, which will also be the first Y coordinate of the constructed Triangle.

`width` number

The length of the side which is to the left or to the right of the right angle.

`height` number

The length of the side which is above or below the right angle.

Since: 3.0.0
Source: src/geom/triangle/BuildRight.js (Line 13)
##### Returns:

The constructed right Triangle.

Type
Phaser.Geom.Triangle

#### <static> CenterOn(triangle, x, y [, centerFunc])

Positions the Triangle so that it is centered on the given coordinates.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The triangle to be positioned.

`x` number

The horizontal coordinate to center on.

`y` number

The vertical coordinate to center on.

`centerFunc` CenterFunction <optional>

The function used to center the triangle. Defaults to Centroid centering.

Since: 3.0.0
Source: src/geom/triangle/CenterOn.js (Line 18)
##### Returns:

The Triangle that was centered.

Type
Phaser.Geom.Triangle

#### <static> Centroid(triangle [, out])

Calculates the position of a Triangle's centroid, which is also its center of mass (center of gravity).

The centroid is the point in a Triangle at which its three medians (the lines drawn from the vertices to the bisectors of the opposite sides) meet. It divides each one in a 2:1 ratio.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to use.

`out` Phaser.Geom.Point | object <optional>

An object to store the coordinates in.

Since: 3.0.0
Source: src/geom/triangle/Centroid.js (Line 13)
##### Returns:

The `out` object with modified `x` and `y` properties, or a new Point if none was provided.

Type
Phaser.Geom.Point | object

#### <static> CircumCenter(triangle [, out])

Computes the circumcentre of a triangle. The circumcentre is the centre of the circumcircle, the smallest circle which encloses the triangle. It is also the common intersection point of the perpendicular bisectors of the sides of the triangle, and is the only point which has equal distance to all three vertices of the triangle.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to get the circumcenter of.

`out` Phaser.Math.Vector2 <optional>

The Vector2 object to store the position in. If not given, a new Vector2 instance is created.

Since: 3.0.0
Source: src/geom/triangle/CircumCenter.js (Line 30)
##### Returns:

A Vector2 object holding the coordinates of the circumcenter of the Triangle.

Type
Phaser.Math.Vector2

#### <static> CircumCircle(triangle [, out])

Finds the circumscribed circle (circumcircle) of a Triangle object. The circumcircle is the circle which touches all of the triangle's vertices.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to use as input.

`out` Phaser.Geom.Circle <optional>

An optional Circle to store the result in.

Since: 3.0.0
Source: src/geom/triangle/CircumCircle.js (Line 11)
##### Returns:

The updated `out` Circle, or a new Circle if none was provided.

Type
Phaser.Geom.Circle

#### <static> Clone(source)

Clones a Triangle object.

##### Parameters:
Name Type Description
`source` Phaser.Geom.Triangle

The Triangle to clone.

Since: 3.0.0
Source: src/geom/triangle/Clone.js (Line 9)
##### Returns:

A new Triangle identical to the given one but separate from it.

Type
Phaser.Geom.Triangle

#### <static> Contains(triangle, x, y)

Checks if a point (as a pair of coordinates) is inside a Triangle's bounds.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to check.

`x` number

The X coordinate of the point to check.

`y` number

The Y coordinate of the point to check.

Since: 3.0.0
Source: src/geom/triangle/Contains.js (Line 9)
##### Returns:

`true` if the point is inside the Triangle, otherwise `false`.

Type
boolean

#### <static> ContainsArray(triangle, points [, returnFirst] [, out])

Filters an array of point-like objects to only those contained within a triangle. If `returnFirst` is true, will return an array containing only the first point in the provided array that is within the triangle (or an empty array if there are no such points).

##### Parameters:
Name Type Argument Default Description
`triangle` Phaser.Geom.Triangle

The triangle that the points are being checked in.

`points` Array.<Phaser.Geom.Point>

An array of point-like objects (objects that have an `x` and `y` property)

`returnFirst` boolean <optional>
false

If `true`, return an array containing only the first point found that is within the triangle.

`out` array <optional>

If provided, the points that are within the triangle will be appended to this array instead of being added to a new array. If `returnFirst` is true, only the first point found within the triangle will be appended. This array will also be returned by this function.

Since: 3.0.0
Source: src/geom/triangle/ContainsArray.js (Line 13)
##### Returns:

An array containing all the points from `points` that are within the triangle, if an array was provided as `out`, points will be appended to that array and it will also be returned here.

Type
Array.<Phaser.Geom.Point>

#### <static> ContainsPoint(triangle, point)

Tests if a triangle contains a point.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The triangle.

`point` Phaser.Geom.Point | Phaser.Math.Vector2 | any

The point to test, or any point-like object with public `x` and `y` properties.

Since: 3.0.0
Source: src/geom/triangle/ContainsPoint.js (Line 9)
##### Returns:

`true` if the point is within the triangle, otherwise `false`.

Type
boolean

#### <static> CopyFrom(source, dest)

Copy the values of one Triangle to a destination Triangle.

##### Parameters:
Name Type Description
`source` Phaser.Geom.Triangle

The source Triangle to copy the values from.

`dest` Phaser.Geom.Triangle

The destination Triangle to copy the values to.

Since: 3.0.0
Source: src/geom/triangle/CopyFrom.js (Line 7)
##### Returns:

The destination Triangle.

Type
Phaser.Geom.Triangle

#### <static> Decompose(triangle [, out])

Decomposes a Triangle into an array of its points.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to decompose.

`out` array <optional>

An array to store the points into.

Since: 3.0.0
Source: src/geom/triangle/Decompose.js (Line 7)
##### Returns:

The provided `out` array, or a new array if none was provided, with three objects with `x` and `y` properties representing each point of the Triangle appended to it.

Type
array

#### <static> Equals(triangle, toCompare)

Returns true if two triangles have the same coordinates.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The first triangle to check.

`toCompare` Phaser.Geom.Triangle

The second triangle to check.

Since: 3.0.0
Source: src/geom/triangle/Equals.js (Line 7)
##### Returns:

`true` if the two given triangles have the exact same coordinates, otherwise `false`.

Type
boolean

#### <static> GetPoint(triangle, position [, out])

Returns a Point from around the perimeter of a Triangle.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to get the point on its perimeter from.

`position` number

The position along the perimeter of the triangle. A value between 0 and 1.

`out` Phaser.Geom.Point | object <optional>

An option Point, or Point-like object to store the value in. If not given a new Point will be created.

Since: 3.0.0
Source: src/geom/triangle/GetPoint.js (Line 10)
##### Returns:

A Point object containing the given position from the perimeter of the triangle.

Type
Phaser.Geom.Point | object

#### <static> GetPoints(triangle, quantity, stepRate [, out])

Returns an array of evenly spaced points on the perimeter of a Triangle.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to get the points from.

`quantity` integer

The number of evenly spaced points to return. Set to 0 to return an arbitrary number of points based on the `stepRate`.

`stepRate` number

If `quantity` is 0, the distance between each returned point.

`out` array | Array.<Phaser.Geom.Point> <optional>

An array to which the points should be appended.

Since: 3.0.0
Source: src/geom/triangle/GetPoints.js (Line 10)
##### Returns:

The modified `out` array, or a new array if none was provided.

Type
array | Array.<Phaser.Geom.Point>

#### <static> InCenter(triangle [, out])

Calculates the position of the incenter of a Triangle object. This is the point where its three angle bisectors meet and it's also the center of the incircle, which is the circle inscribed in the triangle.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to find the incenter of.

`out` Phaser.Geom.Point <optional>

An optional Point in which to store the coordinates.

Since: 3.0.0
Source: src/geom/triangle/InCenter.js (Line 21)
##### Returns:

Point (x, y) of the center pixel of the triangle.

Type
Phaser.Geom.Point

#### <static> Offset(triangle, x, y)

Moves each point (vertex) of a Triangle by a given offset, thus moving the entire Triangle by that offset.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to move.

`x` number

The horizontal offset (distance) by which to move each point. Can be positive or negative.

`y` number

The vertical offset (distance) by which to move each point. Can be positive or negative.

Since: 3.0.0
Source: src/geom/triangle/Offset.js (Line 7)
##### Returns:

The modified Triangle.

Type
Phaser.Geom.Triangle

#### <static> Perimeter(triangle)

Gets the length of the perimeter of the given triangle. Calculated by adding together the length of each of the three sides.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to get the length from.

Since: 3.0.0
Source: src/geom/triangle/Perimeter.js (Line 9)
##### Returns:

The length of the Triangle.

Type
number

#### <static> Random(triangle [, out])

Returns a random Point from within the area of the given Triangle.

##### Parameters:
Name Type Argument Description
`triangle` Phaser.Geom.Triangle

The Triangle to get a random point from.

`out` Phaser.Geom.Point <optional>

The Point object to store the position in. If not given, a new Point instance is created.

Since: 3.0.0
Source: src/geom/triangle/Random.js (Line 9)
##### Returns:

A Point object holding the coordinates of a random position within the Triangle.

Type
Phaser.Geom.Point

#### <static> Rotate(triangle, angle)

Rotates a Triangle about its incenter, which is the point at which its three angle bisectors meet.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to rotate.

`angle` number

The angle by which to rotate the Triangle, in radians.

Since: 3.0.0
Source: src/geom/triangle/Rotate.js (Line 10)
##### Returns:

The rotated Triangle.

Type
Phaser.Geom.Triangle

#### <static> RotateAroundPoint(triangle, point, angle)

Rotates a Triangle at a certain angle about a given Point or object with public `x` and `y` properties.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to rotate.

`point` Phaser.Geom.Point

The Point to rotate the Triangle about.

`angle` number

The angle by which to rotate the Triangle, in radians.

Since: 3.0.0
Source: src/geom/triangle/RotateAroundPoint.js (Line 9)
##### Returns:

The rotated Triangle.

Type
Phaser.Geom.Triangle

#### <static> RotateAroundXY(triangle, x, y, angle)

Rotates an entire Triangle at a given angle about a specific point.

##### Parameters:
Name Type Description
`triangle` Phaser.Geom.Triangle

The Triangle to rotate.

`x` number

The X coordinate of the point to rotate the Triangle about.

`y` number

The Y coordinate of the point to rotate the Triangle about.

`angle` number

The angle by which to rotate the Triangle, in radians.

Since: 3.0.0
Source: src/geom/triangle/RotateAroundXY.js (Line 7)
##### Returns:

The rotated Triangle.

Type
Phaser.Geom.Triangle

#### contains(x, y)

Checks whether a given points lies within the triangle.

##### Parameters:
Name Type Description
`x` number

The x coordinate of the point to check.

`y` number

The y coordinate of the point to check.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 118)
##### Returns:

`true` if the coordinate pair is within the triangle, otherwise `false`.

Type
boolean

#### getLineA( [line])

Returns a Line object that corresponds to Line A of this Triangle.

##### Parameters:
Name Type Argument Description
`line` Phaser.Geom.Line <optional>

A Line object to set the results in. If `undefined` a new Line will be created.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 224)
##### Returns:

A Line object that corresponds to line A of this Triangle.

Type
Phaser.Geom.Line

#### getLineB( [line])

Returns a Line object that corresponds to Line B of this Triangle.

##### Parameters:
Name Type Argument Description
`line` Phaser.Geom.Line <optional>

A Line object to set the results in. If `undefined` a new Line will be created.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 245)
##### Returns:

A Line object that corresponds to line B of this Triangle.

Type
Phaser.Geom.Line

#### getLineC( [line])

Returns a Line object that corresponds to Line C of this Triangle.

##### Parameters:
Name Type Argument Description
`line` Phaser.Geom.Line <optional>

A Line object to set the results in. If `undefined` a new Line will be created.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 266)
##### Returns:

A Line object that corresponds to line C of this Triangle.

Type
Phaser.Geom.Line

#### getPoint(position [, output])

Returns a specific point on the triangle.

##### Parameters:
Name Type Argument Description
`position` number

Position as float within `0` and `1`. `0` equals the first point.

`output` Phaser.Geom.Point | object <optional>

Optional Point, or point-like object, that the calculated point will be written to.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 134)
##### Returns:

Calculated `Point` that represents the requested position. It is the same as `output` when this parameter has been given.

Type
Phaser.Geom.Point | object

#### getPoints(quantity [, stepRate] [, output])

Calculates a list of evenly distributed points on the triangle. It is either possible to pass an amount of points to be generated (`quantity`) or the distance between two points (`stepRate`).

##### Parameters:
Name Type Argument Description
`quantity` integer

Number of points to be generated. Can be falsey when `stepRate` should be used. All points have the same distance along the triangle.

`stepRate` number <optional>

Distance between two points. Will only be used when `quantity` is falsey.

`output` array | Array.<Phaser.Geom.Point> <optional>

Optional Array for writing the calculated points into. Otherwise a new array will be created.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 152)
##### Returns:

Returns a list of calculated `Point` instances or the filled array passed as parameter `output`.

Type
array | Array.<Phaser.Geom.Point>

#### getRandomPoint( [point])

Returns a random point along the triangle.

##### Parameters:
Name Type Argument Description
`point` Phaser.Geom.Point <optional>

Optional `Point` that should be modified. Otherwise a new one will be created.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 171)
##### Returns:

Random `Point`. When parameter `point` has been provided it will be returned.

Type
Phaser.Geom.Point

#### setTo( [x1] [, y1] [, x2] [, y2] [, x3] [, y3])

Sets all three points of the triangle. Leaving out any coordinate sets it to be `0`.

##### Parameters:
Name Type Argument Default Description
`x1` number <optional>
0

`x` coordinate of the first point.

`y1` number <optional>
0

`y` coordinate of the first point.

`x2` number <optional>
0

`x` coordinate of the second point.

`y2` number <optional>
0

`y` coordinate of the second point.

`x3` number <optional>
0

`x` coordinate of the third point.

`y3` number <optional>
0

`y` coordinate of the third point.

Since: 3.0.0
Source: src/geom/triangle/Triangle.js (Line 188)
##### Returns:

This Triangle object.

Type
Phaser.Geom.Triangle