Java Foundation Classes in a Nutshell

You may, on occasion, have the need to create a custom AffineTransform object

fr om a set of six numbers. A number of

AffineTransform constructors and meth-

ods take matrix elements as arguments. These matrix elements are either passed in

explicitly or specified in an array. Note that the matrix-element naming system

used by the

AffineTransform class is differ ent than the system I’ve used here. The

parameter names for

AffineTransform methods are based on the following matrix:







m00

m10

m01

m11

m02

m12







This is nothing more that a differ ent naming scheme for the elements we are

alr eady familiar with:







sx

shy

shx

sy

tx

ty







When matrix elements are passed to or retur ned by an AffineTransform in an

array of

float or double values, they are stor ed in this order:





m00, m10, m01, m11, m01, m12





This corresponds to the following order using our mnemonic names:





sx, shy, sy, tx, ty





Color Spaces

The java.awt.Color class repr esents a color in Java. As we discussed earlier, Java

2D has added several new constructors to the

Color class, to support the creation

of translucent colors. Another important change to the

Color class is support for

arbitrary color spaces. A color space is a system for repr esenting a color using

some characteristic set of axes.

Java 2D introduces the

java.awt.color package for working with color spaces.

The most important piece of this package is the abstract

ColorSpace class, which

repr ...