# Line3

A geometric line segment represented by a start and end point.

## Constructor

### Line3(start : Vector3, end : Vector3)

start — Start of the line segment. Default is `(0, 0, 0)`.
end — End of the line segment. Default is `(0, 0, 0)`.

Creates a new Line3.

## Properties

### # .start : Vector3

Vector3 representing the start point of the line.

### # .end : Vector3

Vector3 representing the end point of the line.

## Methods

### # .applyMatrix4(matrix : Matrix4) → this

Applies a matrix transform to the line segment.

### # .at(t : Float, target : Vector3) → Vector3

t — Use values 0-1 to return a position along the line segment.
target — the result will be copied into this Vector3.

Returns a vector at a certain position along the line. When t = 0, it returns the start vector, and when t = 1 it returns the end vector.

### # .clone() → Line3

Returns a new Line3 with the same start and end vectors as this one.

### # .closestPointToPoint(point : Vector3, clampToLine : Boolean, target : Vector3) → Vector3

point — return the closest point on the line to this point.
clampToLine — whether to clamp the returned value to the line segment.
target — the result will be copied into this Vector3.

Returns the closets point on the line. If clampToLine is true, then the returned value will be clamped to the line segment.

### # .closestPointToPointParameter(point : Vector3, clampToLine : Boolean) → Float

point — the point for which to return a point parameter.
clampToLine — Whether to clamp the result to the range `[0, 1]`.

Returns a point parameter based on the closest point as projected on the line segment. If clampToLine is true, then the returned value will be between 0 and 1.

### # .copy(line : Line3) → this

Copies the passed line's start and end vectors to this line.

### # .delta(target : Vector3) → Vector3

target — the result will be copied into this Vector3.

Returns the delta vector of the line segment (end vector minus the start vector).

### # .distance() → Float

Returns the Euclidean distance (straight-line distance) between the line's start and end points.

### # .distanceSq() → Float

Returns the square of the Euclidean distance (straight-line distance) between the line's start and end vectors.

### # .equals(line : Line3) → Boolean

lineLine3 to compare with this one.

Returns true if both line's start and end points are equal.

### # .getCenter(target : Vector3) → Vector3

target — the result will be copied into this Vector3.

Returns the center of the line segment.

### # .set(start : Vector3, end : Vector3) → this

start — set the start point of the line.
end — set the end point of the line.

Sets the start and end values by copying the provided vectors.