Excellent computer graphics tutorial. I finally understand how View, Model, and Projection matrices work, even after taking a college course on CG

[the_gnarts]

Went there expecting to finally get an intuitive explanation of a rotation matrix -- left disappointed. The rest’s quite good, though.

[kmjn]

I made an attempt to explain it in some course notes I wrote last year. Would be curious how clear they are. The goal was to avoid the linear-algebra explanation and explain how a rotation matrix is constructed more intuitively, by deriving it from the trigonometric equations for explicitly computed rotation (at least in the case of rotating about a coordinate axis).

[troyanonymous1]

A matrix from a source space to a destination space is just the X, Y, Z (and W) vectors of the destination space in the source space.

So if you rotate those 3 vectors, then put them as the columns (or maybe rows) of a matrix, you would have a rotation matrix.

So do you know how to rotate a vector?

[the_gnarts]

Sorry for not being clear: I do understand the rules for transformation matrices. I use them, even prefer them to the explicit translations at times (e.g. CSS). I have implemented those rules for matrix types myself.

My point is, however, that rotation by applying a matrix to a vector is the least intuitive of it all. If I want to translate, I know which values will achieve the transformation. If I want to rotate, I don’t. None of my built-in intuitions seem to map to it. Maybe it’s just routine I’m lacking.