cse1030.drawing

Class Scale

java.lang.Object

cse1030.drawing.Transformation

cse1030.drawing.Scale

public class Scale
extends Transformation

Scale transformations cause objects to stretch or shrink in size. Scale transformations are controlled by two scalar values:

1. sx: the scale factor in the horizontal direction
2. sy: the scale factor in the vertical direction

A positive value of sx greater than 1 causes the object to stretch in the horizontal direction.

A positive value of sx less than 1 causes the object to shrink in the horizontal direction.

A positive value of sy greater than 1 causes the object to stretch in the vertical direction.

A positive value of sy less than 1 causes the object to shrink in the vertical direction.

Author:

CSE1030Z

Constructor Summary

Constructors

Constructor and Description
Scale(String name, double sx, double sy) Create a scale transformation that scales in the horizontal and vertical directions.

Method Summary

Methods

Modifier and Type	Method and Description
Point2D	apply(Point2D p) Apply the scale to a point to produce a new point leaving the original point unchanged.
String	toString() Get a string representation of the scale.
void	transform(Point2D p) Transform a point changing its coordinates.

Methods inherited from class cse1030.drawing.Transformation

getName

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Scale

public Scale(String name,
     double sx,
     double sy)

Create a scale transformation that scales in the horizontal and vertical directions.

Parameters:

name - the name of the transformation

sx - the scale factor in the horizontal direction

sy - the scale factor in the vertical direction

Method Detail

transform

public void transform(Point2D p)

Transform a point changing its coordinates. For a scale of sx and sy the coordinates of the point are transformed as follows:

newx = sx * x
newy = sy * y

Specified by:

transform in class Transformation

See Also:

Transformation.transform(cse1030.drawing.Point2D)

Parameters:

p - the point to transform

apply

public Point2D apply(Point2D p)

Apply the scale to a point to produce a new point leaving the original point unchanged.

Specified by:

apply in class Transformation

See Also:

transform(cse1030.drawing.Point2D), Transformation.apply(cse1030.drawing.Point2D)

Parameters:

p - the point to apply the transformation to

Returns:

a new point equal to scaling the input point p

toString

public String toString()

Get a string representation of the scale. The returned string is the name of the scale followed by the string " : scale of factors " followed by sx followed by " and " followed by sy. For example, a scale of factors sx = 1.55 and sy = 3.008 named T1 has the following string representation:

"T1 : scale of factors 1.55 and 3.008"

Overrides:

toString in class Transformation

See Also:

Transformation.toString()

Returns:

the string representation of the shear