Package diva.canvas

Class DamageRegion

java.lang.Object

diva.canvas.DamageRegion

public abstract class DamageRegion
extends java.lang.Object

A damage region represents a region of the canvas that has been "damaged" and hence needs to be repainted. Damage regions are passed up from a component that creates the damage until they reach the JCanvas, at which point the Swing RepaintManager gets called.

Version:

$Id$

Author:

John Reekie

Pt.AcceptedRating:

Red

Method Summary

Modifier and Type	Method	Description
abstract void	apply(JCanvas canvas)	Tell the damage region to inflict itself on the given JCanvas.
void	checkCacheValid(TransformContext c)	Check transform cache validity.
static DamageRegion	createDamageRegion(TransformContext c, double x, double y, double w, double h)	Create a damage region in this context over the given rectangle.
static DamageRegion	createDamageRegion(TransformContext c, java.awt.geom.Rectangle2D r)	Create a damage region in this context over the given rectangle.
abstract void	extend(java.awt.geom.Rectangle2D r)	Extend the damage region with the given rectangle.
abstract java.awt.geom.Rectangle2D	getBounds()	Get the bounds of this damage region.
TransformContext	getContext()	Get the transform context in which this damage region was created.

Methods inherited from class java.lang.Object

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

Method Detail

apply

public abstract void apply(JCanvas canvas)

Tell the damage region to inflict itself on the given JCanvas.

Parameters:

canvas - The canvas

checkCacheValid

public void checkCacheValid(TransformContext c)

Check transform cache validity. This must be called from the repaint(DamageRegion) method of any component that has a transform context.

Parameters:

c - The TransformContext

createDamageRegion

public static DamageRegion createDamageRegion(TransformContext c,
                                              java.awt.geom.Rectangle2D r)

Create a damage region in this context over the given rectangle.

Parameters:

c - The Transform Context

r - The given rectangle

Returns:

The Damage Region.

createDamageRegion

public static DamageRegion createDamageRegion(TransformContext c,
                                              double x,
                                              double y,
                                              double w,
                                              double h)

Create a damage region in this context over the given rectangle.

Parameters:

c - The Transform Context

x - The x location of a corner of the damage region

y - The y location of a corner of the damage region

w - The width of the damage region

h - The height of the damage region

Returns:

The Damage Region.

extend

public abstract void extend(java.awt.geom.Rectangle2D r)

Extend the damage region with the given rectangle.

Parameters:

r - The rectangle to which to extend to.

getBounds

public abstract java.awt.geom.Rectangle2D getBounds()

Get the bounds of this damage region.

Returns:

The bounds of the damage region.

getContext

public TransformContext getContext()

Get the transform context in which this damage region was created.

Returns:

The transformContext.