prajna.viz.render

Class ArrowEdgeRenderer

java.lang.Object

prajna.viz.render.SimpleEdgeRenderer

prajna.viz.render.ArrowEdgeRenderer

All Implemented Interfaces:

EdgeRenderer

public class ArrowEdgeRenderer
extends SimpleEdgeRenderer

Class which draws a directed edge with an arrow to represent the the direction of the edge. By default, the arrowhead is placed at the middle of the edge line segment (to try to avoid being obscured by nodes). This behavior can be changed by specifying how far along the edge the arrowhead should be drawn.

Author:

Edward Swing

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ArrowEdgeRenderer.ArrowHeadLocation Enumeration representing the location of the arrowhead

Constructor Summary

Constructors

Constructor and Description
ArrowEdgeRenderer()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	drawArrowhead(java.awt.Graphics g, double xApex, double yApex, double angle) Draws the arrowhead.
void	drawEdge(java.awt.Graphics g, java.lang.Object edge, java.awt.Point origLoc, java.awt.Point destLoc) Draws the edge into the Graphics Context.
ArrowEdgeRenderer.ArrowHeadLocation	getArrowheadLocation() Gets the location of the Arrowhead, relative to the edge.
int	getArrowheadSize() Gets the size used for the arrowhead.
int	getOffset() Get the offset used by this renderer when the arrowhead location is set to OFFSET.
boolean	pickEdge(java.lang.Object edge, java.awt.Point pickPoint, java.awt.Point origLoc, java.awt.Point destLoc) Checks whether the specified pick point is within the drawn area for the edge.
void	setArrowheadLocation(ArrowEdgeRenderer.ArrowHeadLocation loc) Sets the location of the Arrowhead, relative to the edge.
void	setArrowheadSize(int size) Sets the size used for the arrowhead.
void	setOffset(int pixelOffset) Set the offset value used to render the arrowhead from the location of the center or destination node.

Methods inherited from class prajna.viz.render.SimpleEdgeRenderer

getColor, getEdgeColor, getEdgePoints, getHighlight, highlightEdge, setColor, setHighlight

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrowEdgeRenderer

public ArrowEdgeRenderer()

Method Detail

drawArrowhead

protected void drawArrowhead(java.awt.Graphics g,
                 double xApex,
                 double yApex,
                 double angle)

Draws the arrowhead.

Parameters:

g - the Graphics context to display in

xApex - the X coordinate of the point of the arrowhead

yApex - the Y coordinate of the point of the arrowhead

angle - the angle that the arrowhead is pointing

drawEdge

public void drawEdge(java.awt.Graphics g,
            java.lang.Object edge,
            java.awt.Point origLoc,
            java.awt.Point destLoc)

Draws the edge into the Graphics Context. Draws a line between the nodes, and then draws an arrowhead at the specified point along the edge. If the arrowhead location is set to MIDDLE, the center point of the edge is the location of the arrowhead. If the arrowhead location is END, the destination coordinate is used as the location. If the arrowhead location is OFFSET, the arrowhead is placed near the destination location, offset by a number of pixels, specified by the setOffset() method.

Specified by:

drawEdge in interface EdgeRenderer

Overrides:

drawEdge in class SimpleEdgeRenderer

Parameters:

g - the Graphics context to display the edge

edge - the edge to display

origLoc - location of the origin node

destLoc - location of the destination node

getArrowheadLocation

public ArrowEdgeRenderer.ArrowHeadLocation getArrowheadLocation()

Gets the location of the Arrowhead, relative to the edge. Valid values are MIDDLE (the default) or END.

Returns:

the arrowhead location

getArrowheadSize

public int getArrowheadSize()

Gets the size used for the arrowhead.

Returns:

size the size of the arrowhead, in pixels

getOffset

public int getOffset()

Get the offset used by this renderer when the arrowhead location is set to OFFSET.

Returns:

the offset value, in pixels

pickEdge

public boolean pickEdge(java.lang.Object edge,
               java.awt.Point pickPoint,
               java.awt.Point origLoc,
               java.awt.Point destLoc)

Checks whether the specified pick point is within the drawn area for the edge.

Specified by:

pickEdge in interface EdgeRenderer

Overrides:

pickEdge in class SimpleEdgeRenderer

Parameters:

edge - the node to check for picking

pickPoint - the coordinate of the point to check

origLoc - location of the origin node

destLoc - location of the destination node

Returns:

whether the point is in the drawn area for this edge

setArrowheadLocation

public void setArrowheadLocation(ArrowEdgeRenderer.ArrowHeadLocation loc)

Sets the location of the Arrowhead, relative to the edge. Valid values are MIDDLE (the default), END, or OFFSET.

Parameters:

loc - the arrowhead location

setArrowheadSize

public void setArrowheadSize(int size)

Sets the size used for the arrowhead.

Parameters:

size - the size of the arrowhead, in pixels

setOffset

public void setOffset(int pixelOffset)

Set the offset value used to render the arrowhead from the location of the center or destination node. The default value is 0.

Parameters:

pixelOffset - the offset, in pixels