Frames

Coordinate systems along a curve. Not sure why this took so long as the maths is quite simple. Was first getting plans along the curve which was relatively easy as you have a normal at any point and an origin. The part I couldn't figure out was then putting points on that plane. Getting a normal vector (from the infinite amount present i.e. the plane at normal to the vector) could be done in pretty much the same way its done in 2D and having the y-value as zero. Which is where I got caught out last night when I used the get 2D normal method from some old code - as in that the z-value was set at zero.

Also one of the stupidest errors ever:

Line lv = new Line(p1s[i], p1s[1 + 1]);

vector v1 = new vector(p1s[i], p1s[1 + 1]);

it took a good hour or two to see that that 'i' was '1'.

Ball of yarn