found::SphericalDistanceDeterminationAlgorithm Class Reference

The DistanceDeterminationAlgorithm class houses the Distance Determination Algorithm. More...

#include <distance.hpp>

Inheritance diagram for found::SphericalDistanceDeterminationAlgorithm:

Collaboration diagram for found::SphericalDistanceDeterminationAlgorithm:

Public Member Functions
	SphericalDistanceDeterminationAlgorithm (decimal radius, Camera &&cam)
	Creates a SphericalDeterminationAlgorithm, which deduces the Position vector of a sattelite from Earth by modeling Earth as a sphere.
PositionVector	Run (const Points &p) override
	Obtains the position of the planet relative to the camera.
Public Member Functions inherited from found::FunctionStage< Points, PositionVector >
	FunctionStage ()=default
	Constructs a new Stage.
virtual	~FunctionStage ()=default
	Destroys this.
void	DoAction () override
	Executes Run (with a stored input and storing the output)
Points &	GetResource ()
	Returns the stored input of this.
PositionVector *&	GetProduct ()
	Returns the stored output of this.
Public Member Functions inherited from found::Stage< Input, Output >
virtual Output	Run (Input input)=0
	Runs this stage.

Protected Member Functions
Vec3	getCenter (const Vec3 &a, const Vec3 &b, const Vec3 &c)
	Returns the center of earth as a 3d Vector.
PositionVector	Run (const Vec3 &a, const Vec3 &b, const Vec3 &c)
	Returns the position of the planet relative to the camera.

Protected Attributes
Camera	cam_
	cam_ field instance describes the camera settings used for the photo taken
decimal	radius_
	radius_ field instance describes the defined radius of earth.
Vec3	center_
	Calculated center vector.
decimal	r_
	Calculated radius.
Protected Attributes inherited from found::FunctionStage< Points, PositionVector >
Points	resource
	The stored input for this.
PositionVector *	product
	The pointer to the stored output for this.

Detailed Description

The DistanceDeterminationAlgorithm class houses the Distance Determination Algorithm.

This algorithm calculates the distance from Earth based on the pixels of Earth's Edge found in the image.

Note

This class assumes that Earth is a perfect sphere

Constructor & Destructor Documentation

SphericalDistanceDeterminationAlgorithm()

found::SphericalDistanceDeterminationAlgorithm::SphericalDistanceDeterminationAlgorithm ( decimal  radius, Camera &&  cam  )

inline

Creates a SphericalDeterminationAlgorithm, which deduces the Position vector of a sattelite from Earth by modeling Earth as a sphere.

Parameters

radius	The radius of Earth
cam	The camera used to capture the picture of Earth

Member Function Documentation

getCenter()

Vec3 found::SphericalDistanceDeterminationAlgorithm::getCenter ( const Vec3 &  a, const Vec3 &  b, const Vec3 &  c  )

protected

Returns the center of earth as a 3d Vector.

Parameters

a	The first point on the edge of Earth
b	The second point on the edge of Earth
c	The third point on the edge of Earth

Returns

The center of earth as a 3d Vector

Precondition

spats.size() >= 3

a, b and c are normalized, projected points from the camera

CirclePt is a vector that points to a point on the plane. We also know the center vector should point to a point on the plane. So, we get (circlePt - center) * circleN = 0. This is equivalent to (center * circleN) = (circlePt * circleN)

We have (center - mid1/mid2) gives us the vector perpendicular to the mid1N/mid2N vector. Hence, (center - mid1)*mid1N = 0. This becomes (mid1N * center) = (mid1N * mid1). (This is the same for mid2) So we have: circleN * center = circleN * circlePt mid1N * center = mid1N * mid1 mid2N * center = mid2N * mid2 This becomes a systems of linear equation

Run() [1/2]

PositionVector found::SphericalDistanceDeterminationAlgorithm::Run ( const Points &  p )

override

Obtains the position of the planet relative to the camera.

Parameters

p	The points on the edge of Earth (in the image taken by the camera given to this)

Returns

PositionVector The position vector of the Earth relative to the camera

Precondition

p must refer to points taken by the camera that was passed to this

Postcondition

If p.size() < 3, then the result is exactly the zero vector

Run() [2/2]

PositionVector found::SphericalDistanceDeterminationAlgorithm::Run ( const Vec3 &  a, const Vec3 &  b, const Vec3 &  c  )

protected

Returns the position of the planet relative to the camera.

Parameters

a	The first point on the edge of Earth
b	The second point on the edge of Earth
c	The third point on the edge of Earth

Returns

PositionVector The position vector of the Earth relative to the camera

Precondition

p must refer to points taken by the camera that was passed to this

p.size() >= 3

a, b and c are normalized, projected points from the camera

Member Data Documentation

radius_

decimal found::SphericalDistanceDeterminationAlgorithm::radius_

protected

radius_ field instance describes the defined radius of earth.

Should be 6378.0 (km)

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The documentation for this class was generated from the following files:

• src/distance/distance.hpp
• src/distance/distance.cpp