Class: Curve

Phaser.Curves. Curve

A Base Curve class, which all other curve types extend.

Based on the three.js Curve classes created by zz85


new Curve(type)

Parameters:
Name Type Description
type string

The curve type.

Since: 3.0.0
Source: src/curves/Curve.js (Line 12)

Members


active :boolean

For a curve on a Path, false means the Path will ignore this curve.

Type:
  • boolean
Since: 3.0.0
Default Value:
  • true
Source: src/curves/Curve.js (Line 80)

arcLengthDivisions :number

The quantity of arc length divisions within the curve.

Type:
  • number
Since: 3.0.0
Default Value:
  • 100
Source: src/curves/Curve.js (Line 50)

cacheArcLengths :Array.<number>

An array of cached arc length values.

Type:
  • Array.<number>
Since: 3.0.0
Default Value:
  • []
Source: src/curves/Curve.js (Line 60)

defaultDivisions :number

The default number of divisions within the curve.

Type:
  • number
Since: 3.0.0
Default Value:
  • 5
Source: src/curves/Curve.js (Line 40)

needsUpdate :boolean

Does the data of this curve need updating?

Type:
  • boolean
Since: 3.0.0
Default Value:
  • true
Source: src/curves/Curve.js (Line 70)

type :string

String based identifier for the type of curve.

Type:
  • string
Since: 3.0.0
Source: src/curves/Curve.js (Line 31)

Methods


draw(graphics [, pointsTotal])

Draws this curve on the given Graphics object.

The curve is drawn using Graphics.strokePoints so will be drawn at whatever the present Graphics stroke color is. The Graphics object is not cleared before the draw, so the curve will appear on-top of anything else already rendered to it.

Parameters:
Name Type Argument Default Description
graphics Phaser.GameObjects.Graphics

The Graphics instance onto which this curve will be drawn.

pointsTotal number <optional>
32

The resolution of the curve. The higher the value the smoother it will render, at the cost of rendering performance.

Since: 3.0.0
Source: src/curves/Curve.js (Line 111)
Returns:

The Graphics object to which the curve was drawn.

Type
Phaser.GameObjects.Graphics

getBounds( [out] [, accuracy])

Returns a Rectangle where the position and dimensions match the bounds of this Curve.

You can control the accuracy of the bounds. The value given is used to work out how many points to plot across the curve. Higher values are more accurate at the cost of calculation speed.

Parameters:
Name Type Argument Default Description
out Phaser.Geom.Rectangle <optional>

The Rectangle to store the bounds in. If falsey a new object will be created.

accuracy number <optional>
16

The accuracy of the bounds calculations.

Since: 3.0.0
Source: src/curves/Curve.js (Line 135)
Returns:

A Rectangle object holding the bounds of this curve. If out was given it will be this object.

Type
Phaser.Geom.Rectangle

getDistancePoints(distance)

Returns an array of points, spaced out X distance pixels apart. The smaller the distance, the larger the array will be.

Parameters:
Name Type Description
distance number

The distance, in pixels, between each point along the curve.

Since: 3.0.0
Source: src/curves/Curve.js (Line 169)
Returns:

An Array of Point objects.

Type
Array.<Phaser.Geom.Point>

getEndPoint( [out])

Get a point at the end of the curve.

Parameters:
Name Type Argument Description
out Phaser.Math.Vector2 <optional>

Optional Vector object to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 189)
Returns:

Vector2 containing the coordinates of the curves end point.

Type
Phaser.Math.Vector2

getLength()

Get total curve arc length

Since: 3.0.0
Source: src/curves/Curve.js (Line 206)
Returns:

The total length of the curve.

Type
number

getLengths( [divisions])

Get a list of cumulative segment lengths.

These lengths are

  • [0] 0
  • [1] The first segment
  • [2] The first and second segment
  • ...
  • [divisions] All segments
Parameters:
Name Type Argument Description
divisions number <optional>

The number of divisions or segments.

Since: 3.0.0
Source: src/curves/Curve.js (Line 222)
Returns:

An array of cumulative lengths.

Type
Array.<number>

getPointAt(u [, out])

Get a point at a relative position on the curve, by arc length.

Parameters:
Name Type Argument Description
u number

The relative position, [0..1].

out Phaser.Math.Vector2 <optional>

A point to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 278)
Returns:

The point.

Type
Phaser.Math.Vector2

getPoints( [divisions] [, stepRate] [, out])

Get a sequence of evenly spaced points from the curve.

You can pass divisions, stepRate, or neither.

The number of divisions will be

  1. divisions, if divisions > 0; or
  2. this.getLength / stepRate, if stepRate > 0; or
  3. this.defaultDivisions

1 + divisions points will be returned.

Parameters:
Name Type Argument Description
divisions number <optional>

The number of divisions to make.

stepRate number <optional>

The curve distance between points, implying divisions.

out array | Array.<Phaser.Math.Vector2> <optional>

An optional array to store the points in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 300)
Returns:

An array of Points from the curve.

Type
array | Array.<Phaser.Math.Vector2>

getRandomPoint( [out])

Get a random point from the curve.

Parameters:
Name Type Argument Description
out Phaser.Math.Vector2 <optional>

A point object to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 349)
Returns:

The point.

Type
Phaser.Math.Vector2

getSpacedPoints( [divisions] [, stepRate] [, out])

Get a sequence of equally spaced points (by arc distance) from the curve.

1 + divisions points will be returned.

Parameters:
Name Type Argument Default Description
divisions number <optional>
this.defaultDivisions

The number of divisions to make.

stepRate number <optional>

Step between points. Used to calculate the number of points to return when divisions is falsy. Ignored if divisions is positive.

out array | Array.<Phaser.Math.Vector2> <optional>

An optional array to store the points in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 370)
Returns:

An array of points.

Type
Array.<Phaser.Math.Vector2>

getStartPoint( [out])

Get a point at the start of the curve.

Parameters:
Name Type Argument Description
out Phaser.Math.Vector2 <optional>

A point to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 411)
Returns:

The point.

Type
Phaser.Math.Vector2

getTangent(t [, out])

Get a unit vector tangent at a relative position on the curve. In case any sub curve does not implement its tangent derivation, 2 points a small delta apart will be used to find its gradient which seems to give a reasonable approximation

Parameters:
Name Type Argument Description
t number

The relative position on the curve, [0..1].

out Phaser.Math.Vector2 <optional>

A vector to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 430)
Returns:

Vector approximating the tangent line at the point t (delta +/- 0.0001)

Type
Phaser.Math.Vector2

getTangentAt(u [, out])

Get a unit vector tangent at a relative position on the curve, by arc length.

Parameters:
Name Type Argument Description
u number

The relative position on the curve, [0..1].

out Phaser.Math.Vector2 <optional>

A vector to store the result in.

Since: 3.0.0
Source: src/curves/Curve.js (Line 472)
Returns:

The tangent vector.

Type
Phaser.Math.Vector2

getTFromDistance(distance [, divisions])

Given a distance in pixels, get a t to find p.

Parameters:
Name Type Argument Description
distance number

The distance, in pixels.

divisions number <optional>

Optional amount of divisions.

Since: 3.0.0
Source: src/curves/Curve.js (Line 492)
Returns:

The distance.

Type
number

getUtoTmapping(u, distance [, divisions])

Given u ( 0 .. 1 ), get a t to find p. This gives you points which are equidistant.

Parameters:
Name Type Argument Description
u number

A float between 0 and 1.

distance number

The distance, in pixels.

divisions number <optional>

Optional amount of divisions.

Since: 3.0.0
Source: src/curves/Curve.js (Line 513)
Returns:

The equidistant value.

Type
number

updateArcLengths()

Calculate and cache the arc lengths.

Since: 3.0.0
Source: src/curves/Curve.js (Line 594)
See:
  • Phaser.Curves.Curve#getLengths()