I know the intent of those two lines (it's for translating the trailer to it's new position relative to the tractor), but as to why the present calculation of t works at all is a mystery to me too! I suspect when the movement or change in heading isn't too great, which is almost all of the time, the calculation will be close enough. For very small movements and rapid heading changes, such as when the machine is moving from a dead stop, you might see the virtual implement spin around, but that's mitigated by the code that just springs the trailer to straight back when thing change too rapidly.
As it was, my t factor would error on pulling the trailer too much to the inside of the turn, but I figured that would probably be okay since most implements tend to draft to the inside of the turn anyway, especially when you have multiple trailers. I suspect there's a method using calculus to work out the curve of the turn, rather than using a straight line, but I also suspect it wouldn't really matter to the ultimate accuracy of the thing!
I think I enjoy the technical aspects of minutia like this than the bigger issues of graphical user interfaces or even actually using AOG for real work! haha.
Glad to see you've got good weather and things have dried out! Got about 3 or 4 tenths of rain in the last 12 hours and it's actually quite welcome. After the flood waters receded, things got dry quickly!
Last edited by torriem; 05-10-2018 at 12:03 PM.