g2d.graph

Class Manifold

java.lang.Object

g2d.graph.Manifold

public class Manifold
extends java.lang.Object

An attempt to speed up two Glyphish methods in large IOPGraph objects. The two methods being:

 Glyphish getGlyphThing(Point2D p2d)
 void paint(Graphics2D g2d, Rectangle2D rect2d)
 

The underlying graph bounds is overlain with a grid of smaller rectangles, called charts. The dimension of these charts are configurable via the fields:

 public static int CHART_W = 1000;
 public static int CHART_H = 1000;
 

or by the parameters to the sole contructor. Currently manifolds are automatically used if the size of the graph exceeds

 public static int THRESHOLD = 200;
 

All these fields need to be set to the desired values before the graph is laid out.

Since:

July 2005.

Author:

Ian A. Mason.

Field Summary

Fields

Modifier and Type	Field and Description
static int	CHART_H The default chart height.
static int	CHART_W The default chart width.
static int	COLUMN Just for code reduction -- used to indicate we are processing columns.
static int	ROW Just for code reduction -- used to indicate we are processing rows.
static int	THRESHOLD The threshold, in graph size, when manifolds are used automatically.

Constructor Summary

Constructors

Constructor and Description
Manifold(int width, int height, int w, int h) Constructs a Manifold object.

Method Summary

Modifier and Type	Method and Description
void	add(Glyphish glyph) Adds glyphish thing to the appropriate charts.
Glyphish	getGlyphThing(java.awt.geom.Point2D p2d) One of the optimized methods, returns the glyph located at the specified point, or null if none exists.
void	paint(java.awt.Graphics2D g2d, java.awt.geom.Rectangle2D rect2d) One of the optimimized methods, paints only those charts that intersect with the given rectangle.

Methods inherited from class java.lang.Object

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

Field Detail

ROW

public static final int ROW

Just for code reduction -- used to indicate we are processing rows.

See Also:

Constant Field Values

COLUMN

public static final int COLUMN

Just for code reduction -- used to indicate we are processing columns.

See Also:

Constant Field Values

THRESHOLD

public static int THRESHOLD

The threshold, in graph size, when manifolds are used automatically.

CHART_W

public static int CHART_W

The default chart width.

CHART_H

public static int CHART_H

The default chart height.

Constructor Detail

Manifold

public Manifold(int width,
                int height,
                int w,
                int h)

Constructs a Manifold object.

Parameters:

width - an int specifying the width of the rectangle being covered.

height - an int specifying the height of the rectangle being covered.

w - an int specifying the width of the covering charts.

h - an int specifying the height of the covering charts.

Method Detail

getGlyphThing

public Glyphish getGlyphThing(java.awt.geom.Point2D p2d)

One of the optimized methods, returns the glyph located at the specified point, or null if none exists.

Parameters:

p2d - a point of interest.

Returns:

the glyphish thing at the desired location.

paint

public void paint(java.awt.Graphics2D g2d,
                  java.awt.geom.Rectangle2D rect2d)

One of the optimimized methods, paints only those charts that intersect with the given rectangle. Doesn't quite follow the painter's algorithm, so may need fixing!

Parameters:

g2d - a Graphics2D object, to be used in the painting process.

rect2d - a Rectangle2D object, the area to be painted.

add

public void add(Glyphish glyph)

Adds glyphish thing to the appropriate charts.

Parameters:

glyph - a Glyphish object