3D Math continued

I'm still playing around with openGL and openFrameworks and some things are falling in it's place finally. I'm working on a project to learn more about 3D math (dot and cross product) and how and when to use these. The Geon visualization of Ars Thanea is one of my inspirations for these tiny applications I'm working on.

Today I played around with the cross product which gives you a perpendicular vector between two other vectors. Somehow a couple of basic concepts with vectors and 3D math weren't clear to me. Though after I started playing with vectors I got a better understanding. One of these was how/what is that perpendicular vector the cross product returns? This is actually to simple, though one need to know how it works; Lets say you've got two vectors: a red and white one. An easy trick to understand vectors is to pick up a couple of stylos. Now take two stylos and put the bottom against each other and move the tips away from one another. Image that you put a white paper against these two stylos; this is your plane. Now when you calculate the cross product, you get a perpendicular vector, pointing away from this paper.

In the images below I've tried to make this clear. The red and white arrows are the vectors and styles you've got. The pink plane touches both of these vectors. The blue vector is the perpendicular one which is the result of the cross product.

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