Skip to Main Content
Physics for Game Developers, 2nd Edition
book

Physics for Game Developers, 2nd Edition

by Bryan Bywalec, David M Bourg
April 2013
Intermediate to advanced content levelIntermediate to advanced
575 pages
15h 54m
English
O'Reilly Media, Inc.
Content preview from Physics for Game Developers, 2nd Edition

Appendix A. Vector Operations

This appendix implements a class called Vector that encapsulates all of the vector operations that you need when writing 2D or 3D rigid-body simulations. Although Vector 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 constructors, 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);
     Vector& operator/=(float s);

     Vector operator-(void);

};

// Constructor
inline Vector::Vector(void)
{
     x = 0;
     y = 0;
     z = 0;
}

// Constructor
inline Vector::Vector(float xi, float yi, float zi)
{
     x = xi;
     y = yi;
     z = zi;
}

Magnitude

The Magnitude method simply calculates the scalar magnitude of the vector according to the formula:

|v| =

This is for ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Game Physics Engine Development, 2nd Edition

Game Physics Engine Development, 2nd Edition

Ian Millington

Publisher Resources

ISBN: 9781449361037Errata PageSupplemental Content