It may be a problem with the view slewing TrackIR stuff.
Yep, looks like you introduced several bugs with that feature. See the first attached screenshot, for example.
There are a number of issues here. First of all, you neglected to include the HUD_nose_x and HUD_nose_y in all the appropriate places, so the FS1 HUD no longer aligns properly. Second of all, it looks like your HUD_get_nose_coordinates function does not default to 0 -- which it should -- when the viewer is level and pointed directly ahead.
I've added the missing HUD_nose_x and HUD_nose_y offsets in hudreticle.cpp so that the FS1 HUD now displays properly; see the second attached screenshot. However, the centering code is still broken. I've disabled it for the time being, so why don't you take a look and see if you can fix it. I bet once you fix that bug, this thread's bug will be fixed as well.
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