Function cv_core::geom::reproject_along_translation

pub fn reproject_along_translation(
    from: Vector2<f32>, 
    to: NormalizedKeyPoint, 
    translation: Vector3<f32>
) -> f32

This function consumes a from xy coordinate, a to NormalizedKeyPoint, and a direction to translate along.

• t the translation vector
• b the from point
• a the to epipolar point
• O the optical center
• @ the virtual image plane

     t<---b
         /
        /
@@@a@@@/@@@@@
   |  /
   | /
   |/
   O

The from coordinate is actually the relative 3d coordinate in camera space, but the z is truncated because it is not required to compute the translation, otherwise it would be a [CameraPoint]. Effectively, from is a [CameraPoint] without a z component.

The to coordinate is just a normalized keypoint that we wish to find the optimal translation to reproject as close as possible to.

The translation is a vector which will be scaled (multiplied) by the return value to get the actual 3d translation to move from from to to in 3d space.

See the document notes/derivation_of_reproject_along_translation.md in the repository for how this was derived.