Hi Tim,

re:
> I know that the mirror function outside of Node Editor requires
> two points to mirror on (on any axis)

It's not actually just 2 points that set up the regular mirror command, it's 2 points _on a construction plane_ . The regular command picks up the plane implicitly from the viewport where you pick the 2 points. So it's actually 3 things are input with the regular mirror command - a coordinate frame (origin point and x,y,z axis directions) plus 2 points in the x/y plane of that coordinate frame. It actually bundles these up as 2 things since it takes the coordinate frame's origin as the first point also.

Looking at the code for the mirror node in transform2.js, it looks like it is expecting to get a coordinate frame for the input and then it's the x-axis line of that coordinate frame that is used as the mirror line.

So to get it to mirror in some other direction that then world x axis you have to give it a coordinate frame that has its x axis direction oriented along the mirror line. I'm not sure how that is done though, there is a FrameByVecs node which takes xaxis and yaxis directions but I don't know why it doesn't also have an origin point input as well.

- Michael