12. Cross product, cont.

• Note: unlike the dot product, the order of vectors is important: if the order is reversed, the reseulting vector is pointing in the opposite direction:

  • u×v = N

  • v×u = -N

• The cross product gives a consistent orientation: given the usual x and y axis in space, the u×v is pointing in the direction of the positive z axis.

• The cross product has numerous purposes, including finding normals and constructing translation matrices.