edu.neu.ccs.gui
Class PlotMarkAlgorithm

java.lang.Object
  edu.neu.ccs.gui.PlotMarkAlgorithm

public abstract class PlotMarkAlgorithm

extends Object

Class PlotMarkAlgorithm defines the requirements for an algorithm that will produce a scalable shape defined in the neighborhood of a given point. This class is intended to be used in constructors for the class PlotMark.

This class provides several static instances of itself.

The following changes were made in 2.6.0:

• The minimum size parameter was reduced from 1 to 0 to permit the base case of each shape to be created.
• A new circle algorithm named BetterCircle was introduced that produces elegant, symmetrical circles for small values of the size parameter.
• The methods QuarterCircleData and BetterCirclePath on which the algorithm BetterCircle is based are made available as public static methods.
• The earlier circle algorithm was renamed as JavaCircle and is still available.
• Algorithms for a “slider thumb” shape have been added.

Since:

2.4.0

Version:

2.6.0

Field Summary

static PlotMarkAlgorithm	Asterisk The asterisk algorithm.
static PlotMarkAlgorithm	BetterCircle The better circle algorithm for creation of plot marks.
static PlotMarkAlgorithm	BluntWedgeE The blunt-wedge-facing-east algorithm.
static PlotMarkAlgorithm	BluntWedgeN The blunt-wedge-facing-north algorithm.
static PlotMarkAlgorithm	BluntWedgeS The blunt-wedge-facing-south algorithm.
static PlotMarkAlgorithm	BluntWedgeW The blunt-wedge-facing-west algorithm.
static PlotMarkAlgorithm	Cross The cross sign algorithm.
static PlotMarkAlgorithm	Diamond The diamond algorithm.
static PlotMarkAlgorithm	HBar The horizontal bar algorithm.
static PlotMarkAlgorithm	JavaCircle The Java circle algorithm.
static PlotMarkAlgorithm	Plus The plus sign algorithm.
static PlotMarkAlgorithm	SharpWedgeE The sharp-wedge-facing-east algorithm.
static PlotMarkAlgorithm	SharpWedgeN The sharp-wedge-facing-north algorithm.
static PlotMarkAlgorithm	SharpWedgeS The sharp-wedge-facing-south algorithm.
static PlotMarkAlgorithm	SharpWedgeW The sharp-wedge-facing-west algorithm.
static PlotMarkAlgorithm	Square The square algorithm.
static PlotMarkAlgorithm	ThumbE The thumb-facing-east algorithm.
static PlotMarkAlgorithm	ThumbN The thumb-facing-north algorithm.
static PlotMarkAlgorithm	ThumbS The thumb-facing-south algorithm.
static PlotMarkAlgorithm	ThumbW The thumb-facing-west algorithm.
static PlotMarkAlgorithm	VBar The vertical bar algorithm.
static PlotMarkAlgorithm	WedgeE The wedge-facing-east algorithm.
static PlotMarkAlgorithm	WedgeN The wedge-facing-north algorithm.
static PlotMarkAlgorithm	WedgeS The wedge-facing-south algorithm.
static PlotMarkAlgorithm	WedgeW The wedge-facing-west algorithm.

Constructor Summary

PlotMarkAlgorithm()

Method Summary

static Shape	BetterCirclePath(int x, int y, int radius) Returns a full circle path with the given center (x,y) and the given radius using the method QuarterCircleData for the computation.
abstract Shape	makeShape(double x, double y, int size) Returns a shape constructed in the neighborhood of the given point and scaled with the given size.
Shape	makeShape(Point2D p, int size) Returns a shape constructed in the neighborhood of the given point and scaled with the given size.
static int[][]	QuarterCircleData(int radius) Returns the data for construction of a quarter circle path of the given radius.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

HBar

public static final PlotMarkAlgorithm HBar

The horizontal bar algorithm.

Produces the line segment path (x-size,y) to (x+size,y).

When used in a PlotMark, the fill setting should be false.

VBar

public static final PlotMarkAlgorithm VBar

The vertical bar algorithm.

Produces the line segment path (x,y-size) to (x,y+size).

When used in a PlotMark, the fill setting should be false.

Plus

public static final PlotMarkAlgorithm Plus

The plus sign algorithm.

Produces the combined path with 2 line segments:

• (x-size,y) to (x+size,y)
• (x,y-size) to (x,y+size)

When used in a PlotMark, the fill setting should be false.

Cross

public static final PlotMarkAlgorithm Cross

The cross sign algorithm.

Produces the combined path with 2 line segments:

• (x-size,y-size) to (x+size,y+size)
• (x+size,y-size) to (x-size,y+size)

When used in a PlotMark, the fill setting should be false.

Asterisk

public static final PlotMarkAlgorithm Asterisk

The asterisk algorithm.

Produces the combined path with 4 line segments:

• (x-size,y) to (x+size,y)
• (x,y-size) to (x,y+size)
• (x-size,y-size) to (x+size,y+size)
• (x+size,y-size) to (x-size,y+size)

When used in a PlotMark, the fill setting should be false.

Square

public static final PlotMarkAlgorithm Square

The square algorithm.

Returns new XSquare(x, y, size).

Diamond

public static final PlotMarkAlgorithm Diamond

The diamond algorithm.

Produces the closed path with 4 vertices:

• (x,y-size)
• (x+size,y)
• (x,y+size)
• (x-size,y)

BetterCircle

public static PlotMarkAlgorithm BetterCircle

The better circle algorithm for creation of plot marks.

Uses the method BetterCirclePath which is in turn based on the method QuarterCircleData. The path produced has 8-fold symmetry about the horizontal, vertical, and two diagonal axes. Its appearance for small values of size is much better than that given by Java's algorithm.

On the other hand, for large values of size, this algorithm is more computationally intensive than the JavaCircle technique.

If size > 16384, this algorithm will revert to the JavaCircle algorithm.

JavaCircle

public static final PlotMarkAlgorithm JavaCircle

The Java circle algorithm.

Returns:

    new XCircle(x, y, size)

This is equivalent to the pure Java call:

    new Ellipse2D.Double(x-size, y-size, 2*size, 2*size)

Warning: For small values of size, the circle constructed by Java does not have 8-fold symmetry about the horizontal, vertical, and two diagonal axes. The circle is therefore not very pleasing aesthetically.

See BetterCircle.

WedgeN

public static final PlotMarkAlgorithm WedgeN

The wedge-facing-north algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+size,y+(2*size))
• (x-size,y+(2*size))

WedgeE

public static final PlotMarkAlgorithm WedgeE

The wedge-facing-east algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-(2*size),y+size)
• (x-(2*size),y-size)

WedgeS

public static final PlotMarkAlgorithm WedgeS

The wedge-facing-south algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-size,y-(2*size))
• (x+size,y-(2*size))

WedgeW

public static final PlotMarkAlgorithm WedgeW

The wedge-facing-west algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+(2*size),y-size)
• (x+(2*size),y+size)

BluntWedgeN

public static final PlotMarkAlgorithm BluntWedgeN

The blunt-wedge-facing-north algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+size,y+size)
• (x-size,y+size)

BluntWedgeE

public static final PlotMarkAlgorithm BluntWedgeE

The blunt-wedge-facing-east algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-size,y+size)
• (x-size,y-size)

BluntWedgeS

public static final PlotMarkAlgorithm BluntWedgeS

The blunt-wedge-facing-south algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-size,y-size)
• (x+size,y-size)

BluntWedgeW

public static final PlotMarkAlgorithm BluntWedgeW

The blunt-wedge-facing-west algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+size,y-size)
• (x+size,y+size)

SharpWedgeN

public static final PlotMarkAlgorithm SharpWedgeN

The sharp-wedge-facing-north algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+size,y+(3*size))
• (x-size,y+(3*size))

SharpWedgeE

public static final PlotMarkAlgorithm SharpWedgeE

The sharp-wedge-facing-east algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-(3*size),y+size)
• (x-(3*size),y-size)

SharpWedgeS

public static final PlotMarkAlgorithm SharpWedgeS

The sharp-wedge-facing-south algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x-size,y-(3*size))
• (x+size,y-(3*size))

SharpWedgeW

public static final PlotMarkAlgorithm SharpWedgeW

The sharp-wedge-facing-west algorithm.

Produces the closed path with 3 vertices:

• (x,y)
• (x+(3*size),y-size)
• (x+(3*size),y+size)

ThumbN

public static final PlotMarkAlgorithm ThumbN

The thumb-facing-north algorithm.

Produces the closed path with 5 vertices:

• (x,y)
• (x+size,y+size)
• (x+size,y+(2*size))
• (x-size,y+(2*size))
• (x-size,y+size)

ThumbE

public static final PlotMarkAlgorithm ThumbE

The thumb-facing-east algorithm.

Produces the closed path with 5 vertices:

• (x,y)
• (x-size,y+size)
• (x-(2*size),y+size)
• (x-(2*size),y-size)
• (x-size,y-size)

ThumbS

public static final PlotMarkAlgorithm ThumbS

The thumb-facing-south algorithm.

Produces the closed path with 5 vertices:

• (x,y)
• (x-size,y-size)
• (x-size,y-(2*size))
• (x+size,y-(2*size))
• (x+size,y-size)

ThumbW

public static final PlotMarkAlgorithm ThumbW

The thumb-facing-west algorithm.

Produces the closed path with 5 vertices:

• (x,y)
• (x+size,y-size)
• (x+(2*size),y-size)
• (x+(2*size),y+size)
• (x+size,y+size)

Constructor Detail

PlotMarkAlgorithm

public PlotMarkAlgorithm()

Method Detail

makeShape

public final Shape makeShape(Point2D p,
                             int size)

Returns a shape constructed in the neighborhood of the given point and scaled with the given size.

If the given point is null, returns an empty shape.

Otherwise calls makeShape(double, double, int).

Parameters:

p - the point defining where to place the shape

size - the scale size

makeShape

public abstract Shape makeShape(double x,
                                double y,
                                int size)

Returns a shape constructed in the neighborhood of the given point and scaled with the given size.

When defined this method may return an empty shape but should not return null.

The scale size should be forced to at least 0 before building the shape.

Parameters:

x - the x-coordinate of the point defining where to place the shape

y - the y-coordinate of the point defining where to place the shape

size - the scale size

QuarterCircleData

public static int[][] QuarterCircleData(int radius)

Returns the data for construction of a quarter circle path of the given radius.

Assume that the int[][] returned has the name data. Then data is normally of size 2. Let:

    int[] xx = data[0];

    int[] yy = data[1];

Then, the array xx contains the x-coordinates of desired data points and the array yy the corresponding y-coordinates. In particular, the arrays have the same length, say, k. The ends of the arrays are as follows:

xx[0] equals radius.

yy[0] equals 0.

xx[k-1] equals 0.

yy[k-1] equals radius.

More generally, the data is constructed to include the boundary points (x,y) whose distance from the origin is less than or equal to radius+0.5. A horizontal or vertical run of boundary points is represented by the two endpoints of the run.

The path associated with the quarter circle data is designed to be symmetrical relative to the main diagonal.

Note that:

• If radius <= 0 returns the array { { 0 }, { 0 } }
• If radius > 16384 returns null.

The latter constraint is due to a desire to do all internal computations in integer arithmetic.

Parameters:

radius - the radius of the desired quarter circle

BetterCirclePath

public static Shape BetterCirclePath(int x,
                                     int y,
                                     int radius)

Returns a full circle path with the given center (x,y) and the given radius using the method QuarterCircleData for the computation. Since that method provides only a quarter of a circle, the remaining path points are generated via symmetry. In particular, 8-fold symmetry about the horizontal, vertical, and two diagonal axes is therefore guaranteed.

If radius > 16384, the method QuarterCircleData cannot be used so this method returns an XCircle-based path instead.

Parameters:

x - the circle x-center

y - the circle y-center

radius - the circle radius