Killer Game Programming in Java

An Overview of Java 2D

Java 2D offers a set of graphics features that address the inadequacies in the older AWT graphics classes. Weaknesses in AWT include only supporting single pixel thickness lines, limited fonts, poor shape manipulation (e.g., no rotation), and no special fills, gradients, or patterns inside shapes.

Java 2D replaces most of the shape primitives in AWT (e.g., rectangles, arcs, lines, ellipses, polygons) with versions that can take double or floating pointing coordinates, though many people still use the old drawLine(), drawRect(), and fillRect() methods. Of more interest is the ability to create arbitrary geometric shapes by using set operations on other shapes with union, intersection, subtraction, and exclusive-or. A GeneralPath class permits a shape to be built from a series of connected lines and curves, and curves can be defined using splines. (A spline's curviness is specified using a series of control point.)

Java 2D distinguishes between shape stroking and filling. Stroking is the drawing of lines and shape outlines, which may employ various patterns and thicknesses. Shape filling can use a solid color (as in AWT), and patterns, color gradients, and images acting as textures.

Affine transformations can be applied to shapes and images, including translation, rotation, scaling, and shearing, and groups of transformations can be composed together. drawImage() can be supplied with such a transformation, which is applied before the image is rendered. Shapes ...