Java Reference
In-Depth Information
Section 13.6 Drawing Arcs
• An arc (p. 575) is drawn as a portion of an oval.
• Arcs sweep from a starting angle by the number of degrees specified by their arc angle (p. 575).
•
Graphics
methods
drawArc
(p. 575) and
fillArc
(p. 575) are used for drawing arcs.
Section 13.7 Drawing Polygons and Polylines
• Class
Polygon
contains methods for creating polygons.
• Polygons are closed multisided shapes composed of straight-line segments.
• Polylines (p. 578) are sequences of connected points.
•
Graphics
method
drawPolyline
(p. 580) displays a series of connected lines.
•
Graphics
methods
drawPolygon
(p. 580) and
fillPolygon
(p. 581) are used to draw polygons.
•
Polygon
method
addPoint
(p. 581) adds pairs of
x
- and
y
-coordinates to the
Polygon
.
Section 13.8 Java 2D API
• The Java 2D API (p. 581) provides advanced two-dimensional graphics capabilities.
• Class
Graphics2D
(p. 581)—a subclass of
Graphics
—is used for drawing with the Java 2D API.
• The Java 2D API's classes for drawing shapes include
Line2D.Double
,
Rectangle2D.Double
,
RoundRectangle2D.Double
,
Arc2D.Double
and
Ellipse2D.Double
(p. 581).
• Class
GradientPaint
(p. 584) helps draw a shape in gradually changing colors—called a gradient
(p. 584).
•
Graphics2D
method
fill
(p. 584) draws a filled object of any type that implements interface
Shape
(
p. 584).
• Class
BasicStroke
(p. 584) helps specify the drawing characteristics of lines.
•
Graphics2D
method
draw
(p. 584) is used to draw a
Shape
object.
• Classes
GradientPaint
(p. 584) and
TexturePaint
(p. 585) help specify the characteristics for
filling shapes with colors or patterns.
• A general path (p. 586) is a shape constructed from straight lines and complex curves and is rep-
resented with an object of class
GeneralPath
(p. 586).
•
GeneralPath
method
moveTo
(p. 587) specifies the first point in a general path.
•
GeneralPath
method
lineTo
(p. 588) draws a line to the next point in the path. Each new call
to
lineTo
draws a line from the previous point to the current point.
•
GeneralPath
method
closePath
(p. 588) draws a line from the last point to the point specified
in the last call to
moveTo
. This completes the general path.
•
Graphics2D
method
translate
(p. 588) is used to move the drawing origin to a new location.
•
Graphics2D
method
rotate
(p. 588) is used to rotate the next displayed shape.
Self-Review Exercises
13.1
Fill in the blanks in each of the following statements:
a)
In Java 2D, method
of class
sets the characteristics of a stroke used
to draw a shape.
b)
Class helps specify the fill for a shape such that the fill gradually changes from
one color to another.
c)
The
method of class
Graphics
draws a line between two points.
d)
RGB is short for
,
and
.
