Flight Director Deviations Ecuations

[ATMaster]

Hi! Does someone know how the two magenta bars of the Flight Director are represented on the PFD?

http://prosim-ar.com/wp-content/uploads/2010/12/pfd.png

Are there any regulation including the equations describing the behavour of the needles? I know how to compute deviations, based on the applicable full scale deflection, but I do not know how this is translated into the bars position, taking into account the fact of the current aircraft heading.

Thanks for your help!

[TinyTim2]

You would need to know a lot more information to be able to quote actual computations . Why do you need exact formulae ?