Understanding OpenGL Matrices
- by Omega
I'm starting to learn about 3D rendering and I've been making good progress. I've picked up a lot regarding matrices and the general operations that can be performed on them.
One thing I'm still not quite following is OpenGL's use of matrices. I see this (and things like it) quite a lot:
x y z n
-------
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
So my best understanding, is that it is a normalized (no magnitude) 4 dimensional, column-major matrix. Also that this matrix in particular is called the "identity matrix".
Some questions:
What is the "nth" dimension?
How and when are these applied?
My biggest confusion arises from how OpenGL makes use of this kind of data.