Class representing a 3D [link:https://en.wikipedia.org/wiki/Vector_space vector]. A 3D vector is an ordered triplet of numbers (labeled x, y, and z), which can be used to represent a number of things, such as:

- A point in 3D space.
- A direction and length in 3D space. In three.js the length will always be the [link:https://en.wikipedia.org/wiki/Euclidean_distance Euclidean distance] (straight-line distance) from (0, 0, 0) to (x, y, z) and the direction is also measured from (0, 0, 0) towards (x, y, z).
- Any arbitrary ordered triplet of numbers.

There are other things a 3D vector can be used to represent, such as momentum vectors and so on, however these are the most common uses in three.js.

```
var a = new THREE.Vector3( 0, 1, 0 );
//no arguments; will be initialised to (0, 0, 0)
var b = new THREE.Vector3( );
var d = a.distanceTo( b );
```

[page:Float x] - the x value of the vector. Default is *0*.

[page:Float y] - the y value of the vector. Default is *0*.

[page:Float z] - the z value of the vector. Default is *0*.

Creates a new [name].

Used to check whether this or derived classes are Vector3s. Default is *true*.

You should not change this, as it is used internally for optimisation.

Adds [page:Vector3 v] to this vector.

Adds the scalar value s to this vector's [page:.x x], [page:.y y] and [page:.z z] values.

Adds the multiple of [page:Vector3 v] and [page:Float s] to this vector.

Sets this vector to [page:Vector3 a] + [page:Vector3 b].

[page:Vector3 axis] - A normalized [page:Vector3].

[page:Float angle] - An angle in radians.

Applies a rotation specified by an axis and an angle to this vector.

Applies euler transform to this vector by converting the [page:Euler] object to a [page:Quaternion] and applying.

Multiplies this vector by [page:Matrix3 m]

Multiplies this vector (with an implicit 1 in the 4th dimension) and m, and divides by perspective.

Applies a [page:Quaternion] transform to this vector.

Returns the angle between this vector and vector [page:Vector3 v] in radians.

The [page:.x x], [page:.y y] and [page:.z z] components of the vector are rounded up to the nearest integer value.

[page:Vector3 min] - the minimum [page:.x x], [page:.y y] and [page:.z z] values.

[page:Vector3 max] - the maximum [page:.x x], [page:.y y] and [page:.z z] values in the desired range

If this vector's x, y or z value is greater than the max vector's x, y or z value, it is replaced by the corresponding value.

If this vector's x, y or z value is less than the min vector's x, y or z value, it is replaced by the corresponding value.

[page:Float min] - the minimum value the length will be clamped to

[page:Float max] - the maximum value the length will be clamped to

If this vector's length is greater than the max value, it is replaced by the max value.

If this vector's length is less than the min value, it is replaced by the min value.

[page:Float min] - the minimum value the components will be clamped to

[page:Float max] - the maximum value the components will be clamped to

If this vector's x, y or z values are greater than the max value, they are replaced by the max value.

If this vector's x, y or z values are less than the min value, they are replaced by the min value.

Returns a new vector3 with the same [page:.x x], [page:.y y] and [page:.z z] values as this one.

Copies the values of the passed vector3's [page:.x x], [page:.y y] and [page:.z z] properties to this vector3.

Sets this vector to [link:https://en.wikipedia.org/wiki/Cross_product cross product] of itself and [page:Vector3 v].

Sets this vector to [link:https://en.wikipedia.org/wiki/Cross_product cross product] of [page:Vector3 a] and [page:Vector3 b].

Computes the distance from this vector to [page:Vector3 v].

Computes the [link:https://en.wikipedia.org/wiki/Taxicab_geometry Manhattan distance] from this vector to [page:Vector3 v].

Computes the squared distance from this vector to [page:Vector3 v]. If you are just comparing the distance with another distance, you should compare the distance squared instead as it is slightly more efficient to calculate.

Divides this vector by [page:Vector3 v].

Divides this vector by scalar [page:Float s].

Sets vector to *( 0, 0, 0 )* if *[page:Float s] = 0*.

Calculate the [link:https://en.wikipedia.org/wiki/Dot_product dot product] of this vector and [page:Vector3 v].

Checks for strict equality of this vector and [page:Vector3 v].

The components of the vector are rounded down to the nearest integer value.

[page:Array array] - the source array.

[page:Integer offset] - ( optional) offset into the array. Default is 0.

Sets this vector's [page:.x x] value to be array[ offset + 0 ], [page:.y y] value to be array[ offset + 1 ]
and [page:.z z] value to be array[ offset + 2 ].

[page:BufferAttribute attribute] - the source attribute.

[page:Integer index] - index in the attribute.

Sets this vector's [page:.x x], [page:.y y] and [page:.z z] values from the [page:BufferAttribute attribute].

[page:Integer index] - 0, 1 or 2.

If index equals 0 returns the [page:.x x] value.

If index equals 1 returns the [page:.y y] value.

If index equals 2 returns the [page:.z z] value.

Computes the [link:https://en.wikipedia.org/wiki/Euclidean_distance Euclidean length] (straight-line length) from (0, 0, 0) to (x, y, z).

Computes the [link:http://en.wikipedia.org/wiki/Taxicab_geometry Manhattan length] of this vector.

Computes the square of the [link:https://en.wikipedia.org/wiki/Euclidean_distance Euclidean length] (straight-line length) from (0, 0, 0) to (x, y, z). If you are comparing the lengths of vectors, you should compare the length squared instead as it is slightly more efficient to calculate.

[page:Vector3 v] - [page:Vector3] to interpolate towards.

alpha - interpolation factor in the closed interval [0, 1].

Linearly interpolate between this vector and [page:Vector3 v], where alpha is the
distance along the line - alpha = 0 will be this vector, and alpha = 1 will be [page:Vector3 v].

[page:Vector3 v1] - the starting [page:Vector3].

[page:Vector3 v2] - [page:Vector3] to interpolate towards.

[page:Float alpha] - interpolation factor in the closed interval [0, 1].

Sets this vector to be the vector linearly interpolated between [page:Vector3 v1] and
[page:Vector3 v2] where alpha is the distance along the line connecting the two vectors
- alpha = 0 will be [page:Vector3 v1], and alpha = 1 will be [page:Vector3 v2].

If this vector's x, y or z value is less than [page:Vector3 v]'s x, y or z value, replace that value with the corresponding max value.

If this vector's x, y or z value is greater than [page:Vector3 v]'s x, y or z value, replace that value with the corresponding min value.

Multiplies this vector by [page:Vector3 v].

Multiplies this vector by scalar [page:Float s].

Sets this vector equal to [page:Vector3 a] * [page:Vector3 b], component-wise.

Inverts this vector - i.e. sets x = -x, y = -y and z = -z.

Convert this vector to a [link:https://en.wikipedia.org/wiki/Unit_vector unit vector] - that is, sets it equal to the vector with the same direction as this one, but [page:.length length] 1.

[page:Camera camera] — camera to use in the projection.

[link:https://en.wikipedia.org/wiki/Vector_projection Projects] the vector with the camera.

[page:Vector3 planeNormal] - A vector representing a plane normal.

[link:https://en.wikipedia.org/wiki/Vector_projection Projects] this vector onto a plane by subtracting this vector projected onto the plane's
normal from this vector.

[link:https://en.wikipedia.org/wiki/Vector_projection Projects] this vector onto another vector.

[page:Vector3 normal] - the normal to the reflecting plane

Reflect the vector off of plane orthogonal to [page:Vector3 normal]. Normal is assumed to
have unit length.

The components of the vector are rounded to the nearest integer value.

The components of the vector are rounded towards zero (up if negative, down if positive) to an integer value.

Sets the [page:.x x], [page:.y y] and [page:.z z] components of this vector.

[page:Integer index] - 0, 1 or 2.

[page:Float value] - [page:Float]

If index equals 0 set [page:.x x] to [page:Float value].

If index equals 1 set [page:.y y] to [page:Float value].

If index equals 2 set [page:.z z] to [page:Float value]

Sets this vector from the cylindrical coordinates [page:Cylindrical c].

Sets this vector's [page:.x x], [page:.y y] and [page:.z z] equal to the column of the [page:Matrix4 matrix] specified by the [page:Integer index].

Sets this vector to the position elements of the [link:https://en.wikipedia.org/wiki/Transformation_matrix transformation matrix] [page:Matrix4 m].

Sets this vector to the scale elements of the [link:https://en.wikipedia.org/wiki/Transformation_matrix transformation matrix] [page:Matrix4 m].

Sets this vector from the spherical coordinates [page:Spherical s].

Set this vector to the vector with the same direction as this one, but [page:.length length] [page:Float l].

Set the [page:.x x], [page:.y y] and [page:.z z] values of this vector both equal to [page:Float scalar].

Replace this vector's [page:.x x] value with [page:Float x].

Replace this vector's [page:.y y] value with [page:Float y].

Replace this vector's [page:.z z] value with [page:Float z].

Subtracts [page:Vector3 v] from this vector.

Subtracts [page:Float s] from this vector's [page:.x x], [page:.y y] and [page:.z z] compnents.

Sets this vector to [page:Vector3 a] - [page:Vector3 b].

[page:Array array] - (optional) array to store the vector to. If this is not provided
a new array will be created.

[page:Integer offset] - (optional) optional offset into the array.

Returns an array [x, y, z], or copies x, y and z into the provided [page:Array array].

Transforms the direction of this vector by a matrix (the upper left 3 x 3 subset of a [page:Matrix4 m]) and then [page:.normalize normalizes] the result.

[page:Camera camera] — camera to use in the projection.

[link:https://en.wikipedia.org/wiki/Vector_projection Unprojects] the vector with the
camera's projection matrix.