OpenGL and FreeBSD

I have always wanted to do everything cross platform but when you dont know what youre doing and dont have much time it tends to be the last thing on your mind. So a few weeks ago I wrote a simple windows application (using OpenGL) to easily display points in 3D space instead of having to draw it on paper (doing vector maths at university at the moment). I also happen to have just set up a computer with FreeBSD (and GNOME).

Vectors

When objects are represented on a computer screen they are stored in memory as a whole lot of points which are joined up and manipulated (mathematically) such that they make pretty pictures. Each point in this imaginary space is called a point, and a line joining two points is called a vector. As you can imagine, to represent a point in two dimensional space you will need two values which represent its location (or coordinate) on a cartesian plane. Vectors are normally dealt with as originating at the origin and ending at a given point.

This is an example of a point.

And a vector from the origin to that point.

The length of the vector from its origin to end point is called the magnitude. This is the formula to calculate a vectors magnitude.

For comprehensive explanation on vectors check out the wikipedia entry.

Learn Maths

If you ever intend creating your own game (using those simple game creator applications don’t count) you will most definitely need a strong knowledge of algebra! I am currently taking a maths subject at university and am finding it rather difficult. I have found the site Purplemath which has loads of really good algebra tutorials. You can also pay them to tutor you, but the free material is really quite good.

Here are a few more maths algebra resources to consider:

• http://math.about.com/od/algebra/Algebra_Help_Tutorials.htm
• http://www.wtamu.edu/academic/anns/mps/math/mathlab/col_algebra/
• http://www.math.armstrong.edu/MathTutorial/
• http://www.sosmath.com/algebra/algebra.html

Also I found the following page helps me keep an overview of everything I have covered thus far.

XNA Game Studio Express

For those interested, I had previously started a blog with the intention of posting tutorials using XNA Game Studio Express. I did not continue with that series for a few reasons, but for anyone interested it can still be found at this address. In its current state of completeness it will be most beneficial to beginners who have never used XNA before. As always, some programming knowledge is required.