georegression.geometry

Class UtilEllipse_F32

java.lang.Object

georegression.geometry.UtilEllipse_F32

public class UtilEllipse_F32
extends java.lang.Object

Functions for extracting information from ellipses and converting between different ellipse formats.

Constructor Summary

Constructors

Constructor and Description
UtilEllipse_F32()

Method Summary

Modifier and Type	Method and Description
static float	computeAngle(Point2D_F32 p, EllipseRotated_F32 ellipse) Computes the value of 't' used to specify a point's location
static Point2D_F32	computePoint(float t, EllipseRotated_F32 ellipse, Point2D_F32 output) Computes the point on the ellipse at location 't', where t is an angle in radians
static EllipseRotated_F32	convert(EllipseQuadratic_F32 input, EllipseRotated_F32 output) Convert from quadratic to rotated formats.
static EllipseQuadratic_F32	convert(EllipseRotated_F32 input, EllipseQuadratic_F32 output) Convert from rotated to quadratic.
static float	evaluate(float x, float y, EllipseQuadratic_F32 ellipse) Computes the value of the quadratic ellipse function at point (x,y).
static float	evaluate(float x, float y, EllipseRotated_F32 ellipse) Computes the value of the quadratic ellipse function at point (x,y).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

UtilEllipse_F32

public UtilEllipse_F32()

Method Detail

convert

public static EllipseRotated_F32 convert(EllipseQuadratic_F32 input,
                                         EllipseRotated_F32 output)

Convert from quadratic to rotated formats. Equations taken from [1].

[1] David Eberly "Information About Ellipses", Geometric Tools, LLC 2011

Parameters:

input - Input in quadratic format.

output - (Optional) Storage for converted format. Can be null.

Returns:

Ellipse in rotated format.

convert

public static EllipseQuadratic_F32 convert(EllipseRotated_F32 input,
                                           EllipseQuadratic_F32 output)

Convert from rotated to quadratic.

Parameters:

input - Input rotated format.

output - (Optional) Storage for quadratic format. Can be null.

Returns:

Ellipse in quadratic format.

evaluate

public static float evaluate(float x,
                             float y,
                             EllipseQuadratic_F32 ellipse)

Computes the value of the quadratic ellipse function at point (x,y). Should equal 0 if the point is along the ellipse.

Parameters:

x - x-coordinate

y - y-coordinate

ellipse - Ellipse equation being evaluated.

Returns:

value of ellipse equation at point (x,y)

evaluate

public static float evaluate(float x,
                             float y,
                             EllipseRotated_F32 ellipse)

Computes the value of the quadratic ellipse function at point (x,y). Should equal 1 if the point is on the ellipse.

Parameters:

x - x-coordinate

y - y-coordinate

ellipse - Ellipse equation being evaluated.

Returns:

value of ellipse equation at point (x,y)

computePoint

public static Point2D_F32 computePoint(float t,
                                       EllipseRotated_F32 ellipse,
                                       Point2D_F32 output)

Computes the point on the ellipse at location 't', where t is an angle in radians

Parameters:

t - An angle in radians from 0 to 2*PI

ellipse - Ellipse

output - (Optional) point on the ellipse . Can be null.

Returns:

Point on the ellipse

computeAngle

public static float computeAngle(Point2D_F32 p,
                                 EllipseRotated_F32 ellipse)

Computes the value of 't' used to specify a point's location

Parameters:

p - Point on the ellipse

ellipse - Ellipse

Returns:

Angle from -pi to pi