These tutorials focus mainly on OpenGL, Win32 programming and the ODE physics engine. OpenGL has moved on to great heights and I don't cover the newest features but cover all of the basic concepts you will need with working example programs.
Working with the Win32 API is a great way to get to the heart of Windows and is just as relevant today as ever before. Whereas ODE has been marginalized as hardware accelerated physics becomes more common.
Games and graphics utilities can be made quickly and easily using game engines like Unity so this and Linux development in general will be the focus of my next tutorials.
Portals
By Alan Baylis 30/01/2002
Download for Visual Studio 7.0
To calculate the potentially visible set (PVS) of leaves I have decided to use portals. This example calculates the non-arbitrary portals based on the partitioning planes in the BSP tree. I call them non-arbitrary because they are not added manually to the world data as they are in other editors such as MaxEd (the editor for Max Payne), in other words, if the world geometry changes the portals will be recalculated automatically. Next month I will release the calculation of the PVS but I have yet to decide on the final process.