Other rigidbody code before calculates internal data from state data

194 Chapter 10 Laws of Motion for Rigid Bodies

Excerpt from include/cyclone/body.h

/** * Holds the angular orientation of the rigid body in world space. / Quaternion orientation; /* * Holds a transform matrix for converting body space into world * space and vice versa. This can be achieved by calling the * getPointIn*Space functions. Matrix4 transformMatrix;

I call this “derived data,” and it is the first of a handful we’ll add to the rigid body. If you are working on a highly memory-starved machine, you may want to remove these data: they are only copies of existing information in a more convenient form. You can simply calculate them as they are needed. The same is true for all the derived data I will add to the rigid body.

Let’s add a function to the class to calculate the transform matrix and a function to calculate all derived data. Initially calculateDerivedData will only calculate the transform matrix:

Excerpt from src/body.cpp

/** * and orientation.

2*orientation.k*orientation.k;
const Vector3 &position,

const Quaternion &orientation)

* Inline function that creates a transform matrix from a position