Game Development Reference

In-Depth Information

APPENDIX A

Vector Operations

This appendix implements a class called
Vector
that encapsulates all of the vector op‐

erations that you need when writing 2D or 3D rigid-body simulations. Although
Vec

tor
represents 3D vectors, you can easily reduce it to handle 2D vectors by eliminating

all of the
z
terms or simply constraining the
z
terms to 0 where appropriate in your

implementation.

Vector Class

The
Vector
class is defined with three components—
x
,
y
, and
z
—along with several

methods and operators that implement basic vector operations. The class has two con‐

structors, one of which initializes the vector components to 0, and the other of which

initializes the vector components to those passed to the constructor:

//------------------------------------------------------------------------

// Vector Class and vector functions

//------------------------------------------------------------------------

class Vector {

public:

float x;

float y;

float z;

Vector(void);

Vector(float xi, float yi, float zi);

float Magnitude(void);

void Normalize(void);

void Reverse(void);

Vector& operator+=(Vector u);

Vector& operator-=(Vector u);

Vector& operator*=(float s);