What''s a well worded definition of the different uses of a cross product and dot product in game programming? I know what they are and how to use them but summarizing this is proving difficult.

The most common use of the cross product is to calculate a vector that is perpendicular to two other vectors. This obviously comes into play when finding surface normals. It can also be used to find the area of parallelagrams.

Dot products are used to find the angle between two vectors, and can also be used to find the distance between points and planes.

Those are just a few uses.

Dot products are very useful for projecting a vector onto another vector.

I''m not sure if this is overkill or not, but I know that the cross product can be used to determine which ''way'' to rotate. You can use the dot product to calculate how much to rotate, and the cross product to determine which way to rotate.

That, and normals.