I'm trying to create a HUD (heads-up display).
Looking through a camera, I have a HUD.
The two main components of the HUD are a circle around a horizon line (──┼──).
At 0,0, the horizon line rests at the center of the circle.
Like an airplane, when the (camera) nose pitches up (or down), the horizon line moves down (or up); to the left it moves right and to the right it moves left.
Herein lies the rub:
At the point at which the horizon line's cross-hair (it's center) reaches the boundary of the circle, it should stop, constrained to the inside of the circle; despite the camera's continuing rotation.
I have dynamic control over the both x,y orientations of the camera (Xx,Xy & Yx,Yy) and am able to constrain the horizon line to a square(shape) surrounding the circle but am stumped on constraining to within the circle.
A little help would be much appreciated.
DdK
