Some comments to a 2 years old friend as I was cleaning my stuffs ;-)
I don't understand the purpose of the comments.
We can just say that it returns the dot or the cross product, it's simpler ;-)

/ps/trunk/binaries/data/mods/public/globalscripts/vector.js
95	I didn't, don't and won't care about that, but Returns for consistency. (I know you like those things :p) 'the' is false. And as the code do more, speaking of rotation (and orientation) could be +++.
106	Among many other things
114	The second "the" is false. For consistency with the previous one, ...
115	I don't understand the comment

fatherbushido removed a subscriber: fatherbushido.Nov 12 2017, 5:55 PM

Some comments to a 2 years old friend as I was cleaning my stuffs ;-)

I'm getting(got) old. :S

Thanks for your feedback.

We can just say that it returns the dot or the cross product, it's simpler ;-)

Without the geometric interpretation, I wasn't able to understand some operations, for example this one (which is a yet to be committed follow up of the commit of this commit, i.e. rP20429).
While I had lots of linear algebra at school and university, I never saw a one-line computation of the distance of a point from a line in 2D space (used by the rivers map):

/**
 * Returns the distance of a point from a line.
 * @param {Vector2D} - lineStart, lineEnd, point
 * @param {boolean} absolute - If true, the function returns a non-negative number of the magnitude.
 *   Otherwise the sign denotes the direction.
 */
function distanceOfPointFromLine(lineStart, lineEnd, point, absolute = true)
{
	// Since the cross product is the area of the parallelogram with the vectors for sides and
	// one of the two vectors having length one, that area equals the distance between the points.
	let distance = Vector2D.sub(lineStart, lineEnd).normalize().cross(Vector2D.sub(point, lineEnd));
	return absolute ? Math.abs(distance) : distance;
}

(So I intended to retain these findings, including the intermediate ones.)

I'll look into clarifying the comments further on next occasion.

/ps/trunk/binaries/data/mods/public/globalscripts/vector.js
95	Yeah well. (Speaking of consistency, also the two cross product parallelogram comments differ in phrasing). Sure, there are two and I didn't describe the orientation. The idea was to use the geometric definition of perpendicular, https://en.wikipedia.org/wiki/Perpendicular. In particular I wanted to use the special word we have for the 90° angle while we don't have special words for the other angles. I guess mostly a clarification could be added stating which of the two orthogonal vectors is returned.
115	I squashed two sentences into one possibly awkward one: The returned number is the length of said 3D vector. The returned number is the area of a parallelogram where each side of the parallelogram is described by one of the two vectors.
280	(I did notice the article here but not above)