Learning Java

Filling Shapes

Iguana fills its shapes with a number of colors, using the setPaint( ) method of Graphics2D. setPaint( ) sets the current color in the graphics context, so we set it to a different color before each drawing operation. This method accepts any object that implements the Paint interface. The 2D API includes three implementations of this interface, representing solid colors, color gradients, and textures.

Solid Colors

The java.awt.Color class handles color in Java. A Color object describes a single color. You can create an arbitrary Color by specifying the red, green, and blue values, either as integers between 0 and 255 or as floating-point values between 0.0 and 1.0. You can also use getColor( ) to look up a named color in the system properties table, as described in Chapter 9. getColor( ) takes a String color property name, retrieves the integer value from the Properties list, and returns the Color object that corresponds to that color.

The Color class also defines a number of static final color values; these are what we used in the Iguana example. These constants, such as Color.black and Color.red, provide a convenient set of basic color objects for your drawings.

Color Gradients

A color gradient is a smooth blend from one color to another. The GradientPaint class encapsulates this idea in a handy implementation of the Paint interface. All you need to do is specify two points and the color at each point. The GradientPaint will take care of the details so ...