My first collision algorithm

Introduction

When I started 3D programming I soon realized that a lot of things I gave for granted on all the games I played, weren’t so. For example in a 3D world there are only textures and triangles to be drawn. Collisions and a lot of things alike have to be created on your own. That means that if you want the camera not to pass through a wall you have to create an internal geometric representation of the wall and manage the logic yourself.
I want to point out that there are many approaches for handling collisions. I am only showing my approach, I think that everything should be from simple to complex. I have seen so many people trying to enter to the 3D programming world but most of them back out because a lot of tutorials demand previous background of so many areas of knowledge that people get usually overwhelmed.
About the math used in this article, I studied it at school when I was about 12 years old, so I guess you don’t need to have a solid background to understand this and won’t be rocket science.
I say again this algorithm its only my approach I think there are far more better on the web but this one its pretty simple and it puts you on the right way.

3D simulation of a lathe using solids of revolution, C# and openGL

Last month a teacher from my former college call me telling me that they were going to model all the machines in their mechanical workshop and that they will simulate all ther procesess in a 3D enviroment. They were starting with a lathe, but there was a problem, they had no idea how to make the lowering of the pieces with the lathe's blades.