# Vector Class

The vector class holds a single 3 component vector. A vector describes a direction in space, and it's important to use a vector or Position as appropriate for the data that is being calculated. When being multiplied by a Matrix, this class will implicitly have a 4th component (W component) of 0. A new vector can be created without any arguments, with 3 arguments for the x,y,z values, or with a single argument which is a variable that has 3 entries such as a list of length 3, or a position or vector. Examples of creating a vector:

```
v = tdu.Vector() # starts as (0, 0, 0)
v2 = tdu.Vector(0, 0, -1)
values = [0, 1, 0]
v3 = tdu.Vector(values)
```

## Members

`x`

→ `float`

:

Gets or sets the X component of the vector.

`y`

→ `float`

:

Gets or sets the Y component of the vector.

`z`

→ `float`

:

Gets or sets the Z component of the vector.

## Methods

`angle(vec)`

→ `float`

:

Returns the angel (in degrees) between the current vector and specified vector (vec).

d = v.angle(v2)

`scale(x, y, z)`

→ `None`

:

Scales each component of the vector by the specified values.

- x, y, z - The values to scale each component of the vector by.
v.scale(1, 2, 1)

`normalize()`

→ `None`

:

Makes the length of this vector 1.

m.normalize()

`length()`

→ `float`

:

Returns the length of this vector.

l = m.length()

`lengthSquared()`

→ `float`

:

Returns the squared length of this vector.

l = v.lengthSquared()

`copy()`

→ `tdu.Vector`

:

Returns a new vector that is a copy of the vector.

newV = v.copy()

`distance(vec)`

→ `float`

:

Returns the distance of the current vector to specified vector (vec).

l = v.distance(v2)

`lerp(vec2, t)`

→ `tdu.Vector`

:

Returns the linear interpolation of this vector and vec2. That is vec1 * (1.0 - t) + vec2 * t, where vec1 is the current vector. The value for t is not restricted to the range [0, 1].

l = v.lerp(v2, t)

`slerp(vec2, t)`

→ `tdu.Vector`

:

Returns the spherical interpolation of this vector and vec2. The value for t is not restricted to the range [0, 1].

l = v.slerp(v2, t)

`dot(vec)`

→ `float`

:

Returns the dot product of this vector and the passed vector.

- vec - The other vector to use to calculate the dot product
d = v.dot(otherV)

`cross(vec)`

→ `tdu.Vector`

:

Returns the cross product of this vector and the passed vector. The operation is self cross vec.

- vec - The other vector to use to calculate the cross product.
c = v.cross(otherV)

`project(vec, vec)`

→ `None`

:

Projects this vector onto the plan defined by vec1 and vec2. Both vec1 and vec2 must be normalized. The result may not be normalized.

- vec1, vec2 - The vectors that specify the plane to project onto. Must be normalized.
v.project(v1, v2)

`reflect(vec)`

→ `None`

:

Reflects the current vector about the specified vector (vec).

v.reflect(v2)

### Special Functions

`tdu.Vector[i]`

→ `float`

:

Gets or sets the component of the vector specified by i, where i can be 0, 1, or 2.

y = v[1] v[1] = y * 2.0

`tdu.Vector * float`

→ `tdu.Vector`

:

Scales the vector by the give float scalar and returns a new vector as the result.

v = v * 2.0 v = 2.0 * v

`tdu.Vector + float`

→ `tdu.Vector`

:

Adds the given scalar to all 3 components of the vector and returns a new vector as the result.

v = v + 5.0 v = 5.0 + v

`tdu.Vector - float`

→ `tdu.Vector`

:

Subtracts the given scalar from all 3 components of the vector and returns a new vector as the result.

v = v - 1.5 v = 1.5 - v

`tdu.Vector + tdu.Vector`

→ `tdu.Vector`

:

Adds the two vectors to create a new vector.

v3 = v1 + v2

`tdu.Vector - tdu.Vector`

→ `tdu.Vector`

:

Subtracts the two vectors to create a new vector.

v3 = v1 - v2

`tdu.Vector += tdu.Vector`

→ `tdu.Vector`

:

Adds the 2nd vector to the 1st vector, the 1st vector will contain the result of the operation.

v1 += v2

`tdu.Vector += float`

→ `tdu.Vector`

:

Adds the given scalar to all 3 components of the vector, the vector will contain the result of the operation.

v1 += 0.4

`tdu.Vector -= tdu.Vector`

→ `tdu.Vector`

:

Subtracts the 2nd vector from the 1st vector, the 1st vector will contain the result of the operation.

v1 -= v2

`tdu.Matrix * tdu.Vector`

→ `tdu.Vector`

:

Multiplies the vector by the matrix and returns the a new vector as the result. Since a Vector is direction only and has no notion of a position, the translate part of the matrix does not get applied to the vector.

v = M * v

`tdu.Vector / float`

→ `tdu.Vector`

:

Divides each component of the vector by the scalar and returns the a new vector as the result.

v = v / 0.2

`tdu.Vector *= tdu.Matrix`

→ `tdu.Vector`

:

Multiplies the vector by the matrix, the vector will contain the result. The vector is multiplied on the right of the matrix. This is the same as doing v = M * v, although more efficient since it doesn't require assigning a new vector to v. Since a Vector is direction only and has no notion of a position, the translate part of the matrix does not get applied to the vector.

v *= M

`tdu.Vector *= float`

→ `tdu.Vector`

:

Scales all 3 components of the vector by the given scalar. The vector will contain the result.

v *= 1.1

`tdu.Vector *= tdu.Vector`

→ `tdu.Vector`

:

Does a component-wise scale of all 3 components of the vector by the components of the 2nd vector. The vector will contain the result.

v1 *= v2

`abs(tdu.Vector)`

→ `tdu.Vector`

:

Returns a new vector with all 3 components being the absolute value of the given vector's components.

v2 = abs(v1)

`-tdu.Vector`

→ `tdu.Vector`

:

Returns a new vector with all 3 components being negated.

v2 = -v1