Article: Basic OpenGL Lighting

I have mixed feelings about this article. As stated at the beginning, the article is targeted at beginners, and the author is a beginner himself. And that's exactly the problem.

The author tries to write about a topic he doesn't fully understand himself. There are a few correct parts, a few totally incorrect parts, but mostly broad confusion about terminology and technical concepts.

The article is about OpenGL's built in lighting. The central part of every lighting system is the illumination model, the Phong model in the case of the fixed function pipeline. This illumination model is the core of the entire system, and its understanding is vital in order to grasp concepts such as diffuse or specular light, surface properties or vertex normals. The author doesn't mention it with one word.

He also skims over very important aspects with a simple "Do not panic if you have not understood even a single a word of the last two paragraphs" - I suspect that he didn't understand a single word of them either ;) Yet, this is very important information, such as the actual difference between positional vs. directional light and when to use them, local vs. infinite viewer, or simply the fact that light positions are in eye space (which can drive you mad, if you don't know it).

I personally don't like the idea of beginners writing for beginners, simply because it will spread misconceptions and downright incorrect information. But well, even from an objective point of view, the article contains a lot of fragmentary half truths. It reads more like a personal journal of his experience with OpenGLs lighting (in the order he discovered the functionality) than a well structured article.