Complete Maya Programming Volume II

3.6 Length

23

Figure 3.3 shows the result of scaling the vector a by 2 and - 1. A scaling of - 1 will

cause the vector to be flipped. That is, its direction is reversed.

b--a /

2xa

FIGURE 3.3

Vector scaling.

The algebraic rules for vector scaling are:

(st)a = s(ta)

(s + t)a = sa + ta

s(a + b) = sa + sb

la=a

(Associative property)

(Distributive property)

(Distributive property)

(Multiplicative identity)

3.6

LENGTH

Calculating the length of a vector is done using the standard Pythagorean theorem,

shown in Figure 3.4. This is a right triangle. That is, a triangle with one angle at

90 degrees.

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