A quadratic Bézier curve constructed from two control points.

**Constructor**

`new QuadraticBezier(p0, p1, p2)`

**Parameters**

name | type | optional | description |
---|---|---|---|

p0 | Phaser.Math.Vector2 | Array.<number> | No | Start point, or an array of point pairs. |

p1 | No | Control Point 1. | |

p2 | No | Control Point 2. |

**Scope**: static

**Extends**

Source: src/curves/QuadraticBezierCurve.js#L12

Since: 3.2.0

# Public Members

## active

### active: boolean

**Description:**

For a curve on a Path, `false`

means the Path will ignore this curve.

**Inherits:** Phaser.Curves.Curve#active

Source: src/curves/Curve.js#L80

Since: 3.0.0

## arcLengthDivisions

### arcLengthDivisions: number

**Description:**

The quantity of arc length divisions within the curve.

**Inherits:** Phaser.Curves.Curve#arcLengthDivisions

Source: src/curves/Curve.js#L50

Since: 3.0.0

## cacheArcLengths

### cacheArcLengths: Array.<number>

**Description:**

An array of cached arc length values.

**Inherits:** Phaser.Curves.Curve#cacheArcLengths

Source: src/curves/Curve.js#L60

Since: 3.0.0

## defaultDivisions

### defaultDivisions: number

**Description:**

The default number of divisions within the curve.

**Inherits:** Phaser.Curves.Curve#defaultDivisions

Source: src/curves/Curve.js#L40

Since: 3.0.0

## needsUpdate

### needsUpdate: boolean

**Description:**

Does the data of this curve need updating?

**Inherits:** Phaser.Curves.Curve#needsUpdate

Source: src/curves/Curve.js#L70

Since: 3.0.0

## p0

### p0: Phaser.Math.Vector2

**Description:**

The start point.

Source: src/curves/QuadraticBezierCurve.js#L43

Since: 3.2.0

## p1

### p1: Phaser.Math.Vector2

**Description:**

The first control point.

Source: src/curves/QuadraticBezierCurve.js#L52

Since: 3.2.0

## p2

### p2: Phaser.Math.Vector2

**Description:**

The second control point.

Source: src/curves/QuadraticBezierCurve.js#L61

Since: 3.2.0

## type

### type: string

**Description:**

String based identifier for the type of curve.

**Inherits:** Phaser.Curves.Curve#type

Source: src/curves/Curve.js#L31

Since: 3.0.0

# Private Members

## _tmpVec2A

### _tmpVec2A: Phaser.Math.Vector2

**Description:**

A temporary calculation Vector.

**Access:** private

**Inherits:** Phaser.Curves.Curve#_tmpVec2A

Source: src/curves/Curve.js#L90

Since: 3.0.0

## _tmpVec2B

### _tmpVec2B: Phaser.Math.Vector2

**Description:**

A temporary calculation Vector.

**Access:** private

**Inherits:** Phaser.Curves.Curve#_tmpVec2B

Source: src/curves/Curve.js#L100

Since: 3.0.0

# Public Methods

## draw

### <instance> draw(graphics, [pointsTotal])

**Description:**

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.

**Tags:**

- generic

**Parameters:**

name | type | optional | default | description |
---|---|---|---|---|

graphics | No |
| ||

pointsTotal | number | Yes | 32 | Number of points to be used for drawing the curve. Higher numbers result in smoother curve but require more processing. |

**Overrides:** Phaser.Curves.Curve#draw

**Returns:** Phaser.GameObjects.Graphics - `Graphics`

object that was drawn to.

Source: src/curves/QuadraticBezierCurve.js#L132

Since: 3.2.0

## fromJSON

### <static> fromJSON(data)

**Description:**

Creates a curve from a JSON object, e. g. created by `toJSON`

.

**Parameters:**

name | type | optional | description |
---|---|---|---|

data | No | The JSON object containing this curve data. |

**Returns:** Phaser.Curves.QuadraticBezier - The created curve instance.

Source: src/curves/QuadraticBezierCurve.js#L190

Since: 3.2.0

## getBounds

### <instance> getBounds([out], [accuracy])

**Description:**

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 | optional | default | description |
---|---|---|---|---|

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

accuracy | number | Yes | 16 | The accuracy of the bounds calculations. |

**Returns:** Phaser.Geom.Rectangle - A Rectangle object holding the bounds of this curve. If `out`

was given it will be this object.

**Inherits:** Phaser.Curves.Curve#getBounds

Source: src/curves/Curve.js#L135

Since: 3.0.0

## getDistancePoints

### <instance> getDistancePoints(distance)

**Description:**

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

**Parameters:**

name | type | optional | description |
---|---|---|---|

distance | number | No | The distance, in pixels, between each point along the curve. |

**Returns:** Array.<Phaser.Geom.Point> - An Array of Point objects.

**Inherits:** Phaser.Curves.Curve#getDistancePoints

Source: src/curves/Curve.js#L169

Since: 3.0.0

## getEndPoint

### <instance> getEndPoint([out])

**Description:**

Get a point at the end of the curve.

**Parameters:**

name | type | optional | description |
---|---|---|---|

out | Yes | Optional Vector object to store the result in. |

**Returns:** Phaser.Math.Vector2 - Vector2 containing the coordinates of the curves end point.

**Inherits:** Phaser.Curves.Curve#getEndPoint

Source: src/curves/Curve.js#L189

Since: 3.0.0

## getLength

### <instance> getLength()

**Description:**

Get total curve arc length

**Returns:** number - The total length of the curve.

**Inherits:** Phaser.Curves.Curve#getLength

Source: src/curves/Curve.js#L206

Since: 3.0.0

## getLengths

### <instance> getLengths([divisions])

**Description:**

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 | optional | description |
---|---|---|---|

divisions | number | Yes | The number of divisions or segments. |

**Returns:** Array.<number> - An array of cumulative lengths.

**Inherits:** Phaser.Curves.Curve#getLengths

Source: src/curves/Curve.js#L222

Since: 3.0.0

## getPoint

### <instance> getPoint(t, [out])

**Description:**

Get point at relative position in curve according to length.

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

t | number | No | The position along the curve to return. Where 0 is the start and 1 is the end. |

out | Yes | A Vector2 object to store the result in. If not given will be created. |

**Returns:** Phaser.Math.Vector2 - The coordinates of the point on the curve. If an `out`

object was given this will be returned.

Source: src/curves/QuadraticBezierCurve.js#L105

Since: 3.2.0

## getPointAt

### <instance> getPointAt(u, [out])

**Description:**

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

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

u | number | No | The relative position, [0..1]. |

out | Yes | A point to store the result in. |

**Returns:** Phaser.Math.Vector2 - The point.

**Inherits:** Phaser.Curves.Curve#getPointAt

Source: src/curves/Curve.js#L278

Since: 3.0.0

## getPoints

### <instance> getPoints([divisions], [stepRate], [out])

**Description:**

Get a sequence of evenly spaced points from the curve.

You can pass `divisions`

, `stepRate`

, or neither.

The number of divisions will be

`divisions`

, if`divisions`

> 0; or`this.getLength / stepRate`

, if`stepRate`

> 0; or`this.defaultDivisions`

`1 + divisions`

points will be returned.

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

divisions | number | Yes | The number of divisions to make. |

stepRate | number | Yes | The curve distance between points, implying |

out | array | Array.<Phaser.Math.Vector2> | Yes | An optional array to store the points in. |

**Returns:** array, Array.<Phaser.Math.Vector2> - An array of Points from the curve.

**Inherits:** Phaser.Curves.Curve#getPoints

Source: src/curves/Curve.js#L300

Since: 3.0.0

## getRandomPoint

### <instance> getRandomPoint([out])

**Description:**

Get a random point from the curve.

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

out | Yes | A point object to store the result in. |

**Returns:** Phaser.Math.Vector2 - The point.

**Inherits:** Phaser.Curves.Curve#getRandomPoint

Source: src/curves/Curve.js#L349

Since: 3.0.0

## getResolution

### <instance> getResolution(divisions)

**Description:**

Get the resolution of the curve.

**Parameters:**

name | type | optional | description |
---|---|---|---|

divisions | number | No | Optional divisions value. |

**Returns:** number - The curve resolution.

Source: src/curves/QuadraticBezierCurve.js#L90

Since: 3.2.0

## getSpacedPoints

### <instance> getSpacedPoints([divisions], [stepRate], [out])

**Description:**

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

`1 + divisions`

points will be returned.

**Parameters:**

name | type | optional | default | description |
---|---|---|---|---|

divisions | number | Yes | "this.defaultDivisions" | The number of divisions to make. |

stepRate | number | Yes | 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> | Yes | An optional array to store the points in. |

**Returns:** Array.<Phaser.Math.Vector2> - An array of points.

**Inherits:** Phaser.Curves.Curve#getSpacedPoints

Source: src/curves/Curve.js#L370

Since: 3.0.0

## getStartPoint

### <instance> getStartPoint([out])

**Description:**

Gets the starting point on the curve.

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

out | Yes | A Vector2 object to store the result in. If not given will be created. |

**Overrides:** Phaser.Curves.Curve#getStartPoint

**Returns:** Phaser.Math.Vector2 - The coordinates of the point on the curve. If an `out`

object was given this will be returned.

Source: src/curves/QuadraticBezierCurve.js#L71

Since: 3.2.0

## getTangent

### <instance> getTangent(t, [out])

**Description:**

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

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

t | number | No | The relative position on the curve, [0..1]. |

out | Yes | A vector to store the result in. |

**Returns:** Phaser.Math.Vector2 - Vector approximating the tangent line at the point t (delta +/- 0.0001)

**Inherits:** Phaser.Curves.Curve#getTangent

Source: src/curves/Curve.js#L430

Since: 3.0.0

## getTangentAt

### <instance> getTangentAt(u, [out])

**Description:**

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

**Tags:**

- generic

**Parameters:**

name | type | optional | description |
---|---|---|---|

u | number | No | The relative position on the curve, [0..1]. |

out | Yes | A vector to store the result in. |

**Returns:** Phaser.Math.Vector2 - The tangent vector.

**Inherits:** Phaser.Curves.Curve#getTangentAt

Source: src/curves/Curve.js#L472

Since: 3.0.0

## getTFromDistance

### <instance> getTFromDistance(distance, [divisions])

**Description:**

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

**Parameters:**

name | type | optional | description |
---|---|---|---|

distance | number | No | The distance, in pixels. |

divisions | number | Yes | Optional amount of divisions. |

**Returns:** number - The distance.

**Inherits:** Phaser.Curves.Curve#getTFromDistance

Source: src/curves/Curve.js#L492

Since: 3.0.0

## getUtoTmapping

### <instance> getUtoTmapping(u, distance, [divisions])

**Description:**

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

**Parameters:**

name | type | optional | description |
---|---|---|---|

u | number | No | A float between 0 and 1. |

distance | number | No | The distance, in pixels. |

divisions | number | Yes | Optional amount of divisions. |

**Returns:** number - The equidistant value.

**Inherits:** Phaser.Curves.Curve#getUtoTmapping

Source: src/curves/Curve.js#L513

Since: 3.0.0

## toJSON

### <instance> toJSON()

**Description:**

Converts the curve into a JSON compatible object.

**Returns:** Phaser.Types.Curves.JSONCurve - The JSON object containing this curve data.

Source: src/curves/QuadraticBezierCurve.js#L168

Since: 3.2.0

## updateArcLengths

### <instance> updateArcLengths()

**Description:**

Calculate and cache the arc lengths.

**Inherits:** Phaser.Curves.Curve#updateArcLengths

Source: src/curves/Curve.js#L594

Since: 3.0.0