Package diva.canvas

A Java2D structured graphics package. The Diva canvas is designed to be a useful construction toolkit for interactive 2D editors, viewers, and visualization tools. It aims to be useful and flexible without constraining clients to conventional user interface idioms.

This top-level package, diva.canvas, provides the essential infrastructure of the canvas. Other sub-packages, with the exception of diva.canvas.event (which is also essential) provide additional functionality, complexity, or ease-of-use of the basic infrastructure.

This package provides:

• A Swing component, JCanvas.
• A layered canvas pane, CanvasPane, and a basic implementation, BasicCanvasPane, which provide a screen-independent coordinate system.
• A set of layers, including CanvasLayer and FigureLayer, which map onto a canvas pane and which display graphics or handle events.
• A set of abstract and concrete persistent object classes, including Figure, LeafFigure, SimpleFigure, and CompositeFigure.
• Various support classes and interfaces.

Since:

Ptolemy II 1.0

Interface Summary

Interface	Description
CanvasComponent	A CanvasComponent is an object that can be inserted into the display tree of a JCanvas.
Figure	A Figure is a persistent object drawn on the screen.
FigureContainer	The FigureContainer interface is implemented by any visible component that can contain figures.
FigureSet	The FigureSet interface is the interface implemented by any class that contain references to a set of figures.
GeometricSet	An interface for figure sets with that have their contents defined geometrically.
Site	A site represents a point on a figure.
VisibleComponent	A visible component is a canvas component that is painted onto a graphics context.
ZList	A ZList is an interface for objects that contain an ordered list of figures in z-order.

Class Summary

Class	Description
AbstractFigure	AbstractFigure is an abstract superclass implementing the Figure interface.
AbstractFigureContainer	AbstractFigureContainer is an abstract class that roots the tree of figure-containing classes.
AbstractSite	An abstract implementation of Site.
BasicZList	A basic implementation of the figure z-list, provided for initial implementations of figure containers.
CanvasDebugUtilities	A collection of canvas utilities.
CanvasLayer	A canvas layer is a single layer that lives within a CanvasPane.
CanvasPane	A canvas pane groups canvas layers.
CanvasUtilities	A collection of canvas utilities.
CompositeFigure	A CompositeFigure is a figure that contains a set of child figures.
DamageRegion	A damage region represents a region of the canvas that has been "damaged" and hence needs to be repainted.
FigureDecorator	A FigureDecorator is a figure container that contains a single child figure.
FigureLayer	A figure layer is a layer on which Figures can be drawn.
FigureWrapper	A FigureWrapper is a figure container that contains a single child figure.
GraphicsPane	A CanvasPane which has a default set of layers that are useful for interactive drawing and editing applications.
JCanvas	The JCanvas class is the center-piece of this package.
OverlayLayer	OutlineLayer is a layer that is used to display the grey figures commonly used for drag-selection, reshaping items, and so on.
PaneWrapper	A figure that wraps a whole canvas pane.
SiteDecorator	This is an abstract decorator for sites.
TransformContext	A transform context defines a transformed coordinate system.