Complete Maya Programming Volume II

~/~0 CHAPTER 3 Vectors

C++ API

The triangle's area is calculated using the following.

MVector a( 1.0, 0.0, 0.0 );

MVector b( 0.0, 1.0, 0.0 );

MVector c- a ^ b;

double triArea = 0.5 * c.length();

3.11

POINTS VERSUS VECTORS

Because a point and a vector both have three dimensions, it may seem logical to con-

sider them equivalent. They are, in fact, geometrically and mathematically different.

Geometrically, a vector has a direction and a length, whereas a point has a position.

Mathematically, a point and a vector are represented by homogeneous coordinates as

follows.

P = (Px, Py, Pz, 1)

v = (Vx, Vy, Vz, O)