vector-math
Vector Math
Vector Math functions are global methods that perform operations on arrays, treating them as mathematical vectors.
Unless otherwise specified, Vector Math methods are lenient about dimensions and return a value that is the dimension of the largest input Array object, filling in missing elements with zeros.
Unlike built-in JavaScript methods, such as Math.sin, these methods are not used with the Math prefix.
Example
This expression returns [11, 22, 3]:
add([10, 20], [1, 2, 3])Methods
add()
add(vec1, vec2)
Description
Adds two vectors.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec1 | Array | First vector to add. |
vec2 | Array | Second vector to add. |
Returns
Array
clamp()
clamp(value, limit1, limit2)
Description
The value of each component of value is constrained to fall between the values of the corresponding values of limit1 and limit2.
Parameters
| Parameter | Type | Description |
|---|---|---|
value | Number or Array | Value to clamp. |
limit1 | Number or Array | Minimum amount to clamp value to. |
limit2 | Number or Array | Maximum amount to clamp value to. |
Returns
Number or Array
Example
Ensure that a wiggled amount never exceeds the 0-100 range:
const wiggled = wiggle(0.5, 500);clamp(wiggled, 0, 500);cross()
cross(vec1, vec2)
Description
Returns the vector cross product of vec1 and vec2.
Refer to a math reference or JavaScript guide for more information.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec1 | Array (2- or 3-dimensional) | First vector to calculate cross product of. |
vec2 | Array (2- or 3-dimensional) | Second vector to calculate cross product of. |
Returns
Array (2- or 3-dimensional)
div()
div(vec, amount)
Description
Divides every element of the vector by the amount.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec | Array | The vector to divide |
amount | Number | The amount to divide by |
Returns
Array
dot()
dot(vec1, vec2)
Description
Returns the dot (inner) product of the vector arguments.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec1 | Array | First vector to calculate dot product of. |
vec2 | Array | Second vector to calculate dot product of. |
Returns
Number
length()
length(vec[, point2])
Description
Returns the length of vector vec.
If a second argument is provided, instead treats the first argument as a point and returns the distance between the two points.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec | Array | The vector to normalize, or the first point to measure from. |
point2 | Array | Optional. The second point to measure to. |
Returns
Number
Example
For example, add this expression to the Focus Distance property of a camera to lock the focal plane to the camera’s point of interest so that the point of interest is in focus:
length(position, pointOfInterest)lookAt()
lookAt(fromPoint, atPoint)
Description
Orients a layer to look at a given point, from a given point.
The return value can be used as an expression for the Orientation property, making the z-axis of the layer point at atPoint.
This method is especially useful for cameras and lights.
Parameters
| Parameter | Type | Description |
|---|---|---|
fromPoint | Array (3-dimensional) | The location (in world space) of the layer to orient. |
atPoint | Array (3-dimensional) | The point (in world space) you want to point the layer at. |
Returns
Array (3-dimensional)
Example
This expression on the Orientation property of a spot light makes the light point at the anchor point of layer number 1 in the same composition:
lookAt(position, thisComp.layer(1).position)mul()
mul(vec, amount)
Description
Multiplies every element of the vector by the amount.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec | Array | The vector to multiply |
amount | Number | The amount to multiply by |
Returns
Array
normalize()
normalize(vec)
Description
Normalizes the vector so that its length is 1.0.
Using the normalize method is a short way of performing the operation div(vec, length(vec)).
Parameters
| Parameter | Type | Description |
|---|---|---|
vec | Array | The vector to normalize |
Returns
Array
sub()
sub(vec1, vec2)
Description
Subtracts two vectors.
Parameters
| Parameter | Type | Description |
|---|---|---|
vec1 | Array | The first vector |
vec2 | Array | The second vector |
Returns
Array