Struct cv_core::WorldPoint

pub struct WorldPoint(pub Point3<f64>);

A point in "world" coordinates. This means that the real-world units of the pose are unknown, but the unit of distance and orientation are the same as the current reconstruction.

The reason that the unit of measurement is typically unknown is because if the whole world is scaled by any factor n (excluding the camera itself), then the normalized image coordinates will be exactly same on every frame. Due to this, the scaling of the world is chosen arbitrarily.

To extract the real scale of the world, a known distance between two WorldPoints must be used to scale the whole world (and all translations between cameras). At that point, the world will be appropriately scaled. It is recommended not to make the WorldPoint in the reconstruction scale to the "correct" scale. This is for two reasons:

Firstly, because it is possible for scale drift to occur due to the above situation, the further in the view graph you go from the reference measurement, the more the scale will drift from the reference. It would give a false impression that the scale is known globally when it is only known locally if the whole reconstruction was scaled.

Secondly, as the reconstruction progresses, the reference points might get rescaled as optimization of the reconstruction brings everything into global consistency. This means that, while the reference points would be initially scaled correctly, any graph optimization might cause them to drift in scale as well.

Please scale your points on-demand. When you need to know a real distance in the reconstruction, please use the closest known refenence in the view graph to scale it appropriately. In the future we will add APIs to utilize references as optimization constraints when a known reference reconstruction is present.

Trait Implementations

impl AsMut<Point<f64, U3>> for WorldPoint

fn as_mut(&mut self) -> &mut Point3<f64>

Performs the conversion.

impl AsRef<Point<f64, U3>> for WorldPoint

fn as_ref(&self) -> &Point3<f64>

Performs the conversion.

impl Clone for WorldPoint

fn clone(&self) -> WorldPoint

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for WorldPoint

impl Debug for WorldPoint

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Deref for WorldPoint

type Target = Point3<f64>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl DerefMut for WorldPoint

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl From<Point<f64, U3>> for WorldPoint

fn from(original: Point3<f64>) -> WorldPoint

Performs the conversion.

impl From<WorldPoint> for Point3<f64>

fn from(original: WorldPoint) -> Point3<f64>

Performs the conversion.

impl PartialEq<WorldPoint> for WorldPoint

fn eq(&self, other: &WorldPoint) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &WorldPoint) -> bool

This method tests for !=.

impl PartialOrd<WorldPoint> for WorldPoint

fn partial_cmp(&self, other: &WorldPoint) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &WorldPoint) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &WorldPoint) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &WorldPoint) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &WorldPoint) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for WorldPoint