In this article I’m going to explain homogeneous coordinates (a.k.a. 4D coordinates) as simply as I can. In previous articles, we’ve used 4D vectors for matrix multiplication, but I’ve never really defined what the fourth dimension actually is. Now it’s time to take a closer look at projective geometry.

Also, welcome back! It has been a while since my last post. Hopefully I will find some time in the next couple of months to finish up the Modern OpenGL Series of articles. The code for article 08 is done, but writing the article will take some time.