Hello,

There are a few headers that I don’t mention in the book, or don’t detail in their entirety. This is for the sake of brevity, when the material is tangential to the chief topic, and/or when the classes are relatively simple.

For the two headers you mention, VectorHelper.h and MatrixHelper.h, these files include helper classes to simplify common uses for vectors and matrices. VectorHelper.h includes declarations for 2D, 3D and 4D vector helpers. These classes expose static const vectors like Zero (a vector with zero in each component) and One (a vector with one in each component). There is also a ToString method that represents the vector as an std::string.

For MatrixHelper there’s an Identity static const (representing a 4×4 identity matrix) and methods for getting and setting the Forward, Up, Right, and Translation components contained within a 4×4 matrix.

Paul