org.jdrawing
Class GridDrawingModelCache

java.lang.Object
  org.jdrawing.AbstractDrawingModelCache
      org.jdrawing.GridDrawingModelCache

All Implemented Interfaces:

DrawingModelCache, DrawingModelListener, java.util.EventListener

public class GridDrawingModelCache

extends AbstractDrawingModelCache

implements DrawingModelListener

This implementation of DrawingModelCache optimizes drawing operations by splitting all the drawing area into rectangular cells and caching elements intersecting each cell.

Constructor Summary

GridDrawingModelCache()

Method Summary

void	elementsAdded(DrawingModelEvent event) Invoked after elements have been inserted into the model.
void	elementsChanged(DrawingModelEvent event) Invoked after elements have been changed in some way.
void	elementsRemoved(DrawingModelEvent event) Invoked after elements have been removed from the model.
java.awt.Dimension	getCellSize() Return size of cells used by this cache.
java.lang.Object[]	getElementsForPoint(java.awt.geom.Point2D point) Returns elements which contain a given point.
java.lang.Object[]	getElementsForRectangle(java.awt.geom.Rectangle2D rectangle) Returns elements necessary for repainting a given area.
java.awt.geom.Rectangle2D	getModelBounds2D() Returns the high precision bounding box of all elements of the model.
void	modelChanged(DrawingModelEvent event) Invoked after the model has drastically changed in some way.
void	setCellSize(java.awt.Dimension cellSize) Set size for rectangular cells.
void	setElementRenderer(DrawingElementRenderer renderer) Sets the DrawingElementRenderer that will be used in this cache.
void	setModel(DrawingModel model) Sets the DrawingModel that will be cached by this cache.

Methods inherited from class org.jdrawing.AbstractDrawingModelCache

addDrawingModelCacheListener, fireAreaChanged, fireDrawingChanged, getDrawingModelCacheListeners, getElementRenderer, getModel, getModelBounds, removeDrawingModelCacheListener

Methods inherited from class java.lang.Object

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

Constructor Detail

GridDrawingModelCache

public GridDrawingModelCache()

Method Detail

setModel

public void setModel(DrawingModel model)

Sets the DrawingModel that will be cached by this cache.

Specified by:

setModel in interface DrawingModelCache

Overrides:

setModel in class AbstractDrawingModelCache

Parameters:

model - the DrawingModel that is to be cached

setElementRenderer

public void setElementRenderer(DrawingElementRenderer renderer)

Sets the DrawingElementRenderer that will be used in this cache. Renderer is used to obtain the bounds of an element of the model.

Specified by:

setElementRenderer in interface DrawingModelCache

Overrides:

setElementRenderer in class AbstractDrawingModelCache

Parameters:

renderer - the DrawingElementRenderer that is to be used

setCellSize

public void setCellSize(java.awt.Dimension cellSize)

Set size for rectangular cells. By default size of the cells is 256x256 pixels

Parameters:

cellSize - new size for cells

getCellSize

public java.awt.Dimension getCellSize()

Return size of cells used by this cache.

Returns:

current size of cells

getModelBounds2D

public java.awt.geom.Rectangle2D getModelBounds2D()

Returns the high precision bounding box of all elements of the model.

Specified by:

getModelBounds2D in interface DrawingModelCache

Returns:

the high precision bounding box of all elements of the model

getElementsForRectangle

public java.lang.Object[] getElementsForRectangle(java.awt.geom.Rectangle2D rectangle)

Returns elements necessary for repainting a given area. Elements are returned in order suitable for painting.

Specified by:

getElementsForRectangle in interface DrawingModelCache

Parameters:

rectangle - area that will be repainted

Returns:

elements necessary for repainting

getElementsForPoint

public java.lang.Object[] getElementsForPoint(java.awt.geom.Point2D point)

Returns elements which contain a given point. Elements are returned in order, suitable for painting.

Specified by:

getElementsForPoint in interface DrawingModelCache

Parameters:

point - the Point2D return elements containing given point

elementsAdded

public void elementsAdded(DrawingModelEvent event)

Invoked after elements have been inserted into the model. Notifies all listeners that the area occupied by the inserted element has been changed and updates cache.

Specified by:

elementsAdded in interface DrawingModelListener

Overrides:

elementsAdded in class AbstractDrawingModelCache

Parameters:

event - DrawingModelEvent object encapsulating event information

elementsRemoved

public void elementsRemoved(DrawingModelEvent event)

Invoked after elements have been removed from the model. Notifies all listeners that the area occupied by the removed element has been changed and updates cache.

Specified by:

elementsRemoved in interface DrawingModelListener

Overrides:

elementsRemoved in class AbstractDrawingModelCache

Parameters:

event - DrawingModelEvent object encapsulating event information

elementsChanged

public void elementsChanged(DrawingModelEvent event)

Invoked after elements have been changed in some way. Notifies all listeners that drawing has changed and updates cache.

Specified by:

elementsChanged in interface DrawingModelListener

Overrides:

elementsChanged in class AbstractDrawingModelCache

Parameters:

event - DrawingModelEvent object encapsulating event information

modelChanged

public void modelChanged(DrawingModelEvent event)

Invoked after the model has drastically changed in some way. Notifies all listeners that drawing has changed and updates cache.

Specified by:

modelChanged in interface DrawingModelListener

Overrides:

modelChanged in class AbstractDrawingModelCache

Parameters:

event - DrawingModelEvent object encapsulating event information