maspack.matrix
Class Point2d

java.lang.Object
  maspack.matrix.VectorObject
      maspack.matrix.Vector2d
          maspack.matrix.Point2d

public class Point2d

extends Vector2d

A 2D spatial point. The only difference between a point and a vector is in the the way it is transformed by an affine transformation. In homogeneous coordinates, a point is assigned a 1 in for its third entry, so the affine transformation of a point takes the form
A p + b

Field Summary

Fields inherited from class maspack.matrix.Vector2d

x, y

Constructor Summary

Point2d()
Creates a Point2d and initializes it to zero.

Point2d(double x, double y)
Creates a Point2d with the supplied element values.

Point2d(Vector2d v)
Creates a Point2d by copying a vector

Method Summary

void	inverseTransform(AffineTransform2dObject X) Applies an inverse affine transformation to this point, in place.
void	inverseTransform(AffineTransform2dObject X, Vector2d p1) Applies an inverse affine transformation to the point p1, and places the result in this vector.
void	transform(AffineTransform2dObject X) Applies a affine transformation to this point, in place.
void	transform(AffineTransform2dObject X, Vector2d p1) Applies a affine transformation to the point p1, and places the result in this point.

Methods inherited from class maspack.matrix.Vector2d

absolute, absolute, add, add, angle, combine, cross, cross, distance, distanceSquared, dot, epsilonEquals, equals, get, get, infinityNorm, interpolate, interpolate, inverseTransform, inverseTransform, length, lengthSquared, maxAbsIndex, maxElement, minAbsIndex, minElement, negate, negate, normalize, normalize, oneNorm, perpendicular, scale, scale, scaleAdd, scaleAdd, set, set, set, set, setRandom, setRandom, setRandom, setZero, size, sort, sort, sortAbsolute, sub, sub, transform, transform

Methods inherited from class maspack.matrix.VectorObject

dot, epsilonEquals, equals, equals, get, isFixedSize, norm, normSquared, scan, set, setSize, toString, toString, toString

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Point2d

public Point2d()

Creates a Point2d and initializes it to zero.

Point2d

public Point2d(Vector2d v)

Creates a Point2d by copying a vector

Parameters:

v - vector to be copied

Point2d

public Point2d(double x,
               double y)

Creates a Point2d with the supplied element values.

Parameters:

x - first element

y - second element

Method Detail

transform

public void transform(AffineTransform2dObject X)

Applies a affine transformation to this point, in place.

Overrides:

transform in class Vector2d

Parameters:

X - affine transformation

transform

public void transform(AffineTransform2dObject X,
                      Vector2d p1)

Applies a affine transformation to the point p1, and places the result in this point.

Overrides:

transform in class Vector2d

Parameters:

X - affine transformation

p1 - point to be transformed

inverseTransform

public void inverseTransform(AffineTransform2dObject X)

Applies an inverse affine transformation to this point, in place.

Overrides:

inverseTransform in class Vector2d

Parameters:

X - affine transformation

inverseTransform

public void inverseTransform(AffineTransform2dObject X,
                             Vector2d p1)

Applies an inverse affine transformation to the point p1, and places the result in this vector.

Overrides:

inverseTransform in class Vector2d

Parameters:

X - affine transformation

p1 - point to be transformed