ADOBE AFTER EFFECTS 7.0
User Guide
573
Vector Math methods
Vector Math functions are global methods that perform operations on arrays, treating them as mathematical vectors.
Unlike built-in JavaScript methods, such as
Mat h . s i n
, these methods are not used the
Mat h
prefix . Unless otherwise
specified, Vector Math methods are lenient about dimensions and return a value that is the dimension of the largest
Array, filling in missing elements with zeros. For example, the expression
[ 1 0 , 2 0 ] + [ 1 , 2 , 3 ]
returns
[ 1 1 , 2 2 , 3 ]
.
add(vec1, vec2)
Return type: Array. Adds two vectors.
Argument type:
vec1
and
vec2
are Arrays.
sub(vec1, vec2)
Return type: Array.
Argument type:
vec1
and
vec2
are Arrays.
Subtracts two vectors.
mul(vec, amount)
Return type: Array.
Argument type:
vec
is an Array,
amount
is a Number.
Multiplies every element of the vector by the amount.
div(vec, amount)
Return type: Array.
Argument type:
vec
is an Array,
amount
is a Number.
Divides every element of the vector by the amount.
clamp(value, limit1, limit2)
Return type: Number or Array.
Argument type:
value
,
limit1
, and
limit2
are Numbers or Arrays.
The value of each component of
value
is constrained to fall between the values of the corresponding values of
limit1
and
limit2
.
dot(vec1, vec2)
Return type: Number.
Argument type:
vec1
and
vec2
are Arrays.
Returns the dot (inner) product of the vector arguments.
cross(vec1, vec2)
Return type: Array [2 or 3].
Argument type:
vec1
and
vec2
are Arrays [2 or 3].
Returns the vector cross product of
vec1
and
vec2
. Refer to a math reference or JavaScript guide for more infor-
mation.
normalize(vec)
Return type: Array.
Argument type:
vec
is an Array.
Normalizes the vector so that its length is 1.0. This is a short way of writing
d iv ( ve c , l e ng t h ( ve c ) )
.
length(vec)
Return type: Number.
Argument type:
vec
is an Array.
Returns the length of vector
vec.
length(point1, point2)
Return type: Number.
Argument type:
point1
and
point2
are Arrays.
Summary of Contents for AFTER EFFECTS 7.0
Page 1: ...Chapter 1 User Guide...
