Function mul

mul<T>(a, b, dst?): T
Multiplies two 3-by-3 matrices with a on the left and b on the right
Type Parameters
- T extends BaseArgType = number[]
Parameters
- a: BaseArgType
  The matrix on the left.
- b: BaseArgType
  The matrix on the right.
- Optional dst: T
  matrix to hold result. If not passed a new one is created.
Returns T
The matrix product of a and b.