Java Reference
In-Depth Information
•
Transformation
: Before being stroked and filled, graphics primitives are geo-
metrically transformed. They may be rotated,
translated
(moved),
scaled
(stretched), or otherwise manipulated. The transformation attribute converts
graphicsprimitivesfromuserspacetodevicespace;thedefaulttransformation
maps 72 user space coordinates to one inch on the output device.
•
Composite rule
:
Graphics2D
combines graphics primitive colors with the
drawing surface's existing colors byusingacomposite rule, which determines
the manner in which the combining occurs.
•
Clipping shape
:
Graphics2D
restrictsitsrenderingoperationstotheinterior
of a clipping shape; pixels outside of this shape are not affected. The clipping
shape defaults to the entire drawing surface.
•
Rendering hints
:
Graphics2D
recognizesvariousrenderinghintsthatcanbe
specifiedtocontrolrendering.Forexample,youcanspecify
antialiasing
tore-
move the jagged edges that often surround shapes (e.g., lines) and text.
Graphics primitives enter this pipeline via various
Graphics
methods (e.g.,
drawLine()
and
fillOval()
) and the following
Graphics2D
methods:
•
void fill(Shape s)
fillsashape'sinteriorwiththecurrentpaint.Shapes
implement the
Shape
interface.
•
void draw(Shape s)
draws a shape's outline with the current paint.
• The
drawstring()
methodsdrawtextviacharactershapeswiththecurrent
paint.
• The
drawImage()
methods draw images.
Note
Althoughyoucancall
Graphics
methodstodrawshapes,thesemethodsare
limited in that they only accept integer coordinates. Furthermore, these shapes (apart
from polygon-based shapes) are not reusable. Regarding polygonal shapes, they can
only consist of straight line-segments. In contrast, Java 2D's
Shape
classes, which I
briefly introduce later in this chapter don't have these limitations.
Figure 7-16
conceptualizes the rendering pipeline into separate operations. Opera-
tions could be combined in a particular implementation.
