3D Lingo Dictionary > C-D > dot()

 

dot()

Syntax

vector1.dot(vector2)

Description

3D vector method; returns the sum of the products of the x, y, and z components of two vectors. If both vectors are normalized, the dot is the cosine of the angle between the two vectors.

To manually arrive at the dot of two vectors, multiply the x component of vector1 by the x component of vector2, then multiply the y component of vector1 by the y component of vector2, then multiply the z component of vector1 by the z component of vector2, and finally add the three products together.

This method is identical to dotProduct().

Example

In this example, the angle between the vectors pos5 and pos6 is 45 degrees. The getNormalized function returns the normalized values of pos5 and pos6, and stores them in the variables norm1 and norm2. The dot of norm1 and norm2 is 0.7071, which is the cosine of 45 degrees.

pos5 = vector(100, 100, 0)
pos6 = vector(0, 100, 0)
put pos5.angleBetween(pos6)
-- 45.0000
norm1 = pos5.getNormalized()
put norm1
-- vector( 0.7071, 0.7071, 0.0000 )
norm2 = pos6.getNormalized()
put norm2
-- vector( 0.0000, 1.0000, 0.0000 )
put norm1.dot(norm2)
-- 0.7071

See also

dotProduct(), getNormalized, normalize