prajna.viz.render

Class StepEdgeRenderer

java.lang.Object

prajna.viz.render.StepEdgeRenderer

All Implemented Interfaces:

EdgeRenderer

public class StepEdgeRenderer
extends java.lang.Object
implements EdgeRenderer

Class which draws a Step-style edge. The edge is composed entirely of horizontal and vertical lines. The steps can be formatted to either go horizontally or vertically. (the default).

If the steps are formatted to be vertical, an edge between a pair of nodes will be drawn with a vertical line from the higher node's center, to a horizontal line, then a vertical line to the lower node's center. If there are multiple edges from the higher node, the horizontal line is drawn at the same level, to appear as a continuous line. The same happens with the horizontal style, but with the horizontal and vertical lines switched.

Author:

Edward Swing

Constructor Summary

Constructors

Constructor and Description
StepEdgeRenderer()

Method Summary

Methods

Modifier and Type	Method and Description
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.
protected java.util.List<java.awt.Point>	getAllPoints(java.lang.Object edge, java.awt.Point origLoc, java.awt.Point destLoc) Method to return the sequence of points used to draw a particular edge.
java.awt.Color	getColor() Gets the color for the Renderer
java.util.List<java.awt.Point>	getEdgePoints(java.lang.Object edge, java.awt.Point origLoc, java.awt.Point destLoc) Calculate the sequence of points used to draw the path for a particular edge.
void	highlightEdge(java.awt.Graphics g, java.lang.Object edge, java.awt.Point origLoc, java.awt.Point destLoc) Highlights the edge into the Graphics Context.
boolean	isHorizontal() Returns whether the arrangement is oriented horizontally or vertically
boolean	pickEdge(java.lang.Object edge, java.awt.Point pickPoint, java.awt.Point origLoc, java.awt.Point destLoc) Checks whether the specified pickpoint is within the drawn area for the edge.
void	setColor(java.awt.Color edgeColor) Sets the color for the EdgeRenderer.
void	setHorizontal(boolean horizontalFlag) Sets the initial direction for arrangement.

Methods inherited from class java.lang.Object

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

Constructor Detail

StepEdgeRenderer

public StepEdgeRenderer()

Method Detail

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. This method retrieves the calculated series of points for the step, and draws a polyline.

Specified by:

drawEdge in interface EdgeRenderer

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

getAllPoints

protected java.util.List<java.awt.Point> getAllPoints(java.lang.Object edge,
                                          java.awt.Point origLoc,
                                          java.awt.Point destLoc)

Method to return the sequence of points used to draw a particular edge. The list is returned in a strict order, and includes the arrow head at the end of the edge, next to the destination node.

Parameters:

edge - the GraphEdge to figure the points for

origLoc - location of the origin node

destLoc - location of the destination node

Returns:

a list of points for the edge.

getColor

public java.awt.Color getColor()

Gets the color for the Renderer

Specified by:

getColor in interface EdgeRenderer

Returns:

the color for this renderer

getEdgePoints

public java.util.List<java.awt.Point> getEdgePoints(java.lang.Object edge,
                                           java.awt.Point origLoc,
                                           java.awt.Point destLoc)

Calculate the sequence of points used to draw the path for a particular edge. The list is returned in a strict order. The list does not include any decorative elements, such as arrowheads.

Specified by:

getEdgePoints in interface EdgeRenderer

Parameters:

edge - the GraphEdge to figure the points for

origLoc - location of the origin node

destLoc - location of the destination node

Returns:

a list of points for the edge.

highlightEdge

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

Highlights the edge into the Graphics Context. This renderer uses a thickened line to highlight edges

Specified by:

highlightEdge in interface EdgeRenderer

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

isHorizontal

public boolean isHorizontal()

Returns whether the arrangement is oriented horizontally or vertically

Returns:

true if the arrangement is oriented horizontally, false if it is oriented vertically

pickEdge

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

Checks whether the specified pickpoint is within the drawn area for the edge. For speed, this renderer checks the vertical space directly above the lower node (or the space to the left of the node on the right) since there may be multiple edges obscuring each other coming from the same higher node.

Specified by:

pickEdge in interface EdgeRenderer

Parameters:

edge - the edge 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

setColor

public void setColor(java.awt.Color edgeColor)

Sets the color for the EdgeRenderer. If not set, the default color is black.

Specified by:

setColor in interface EdgeRenderer

Parameters:

edgeColor - the color for this renderer

setHorizontal

public void setHorizontal(boolean horizontalFlag)

Sets the initial direction for arrangement. This determines which direction the arrangement uses for its first tier. If the flag is set to true, the first tier is arranged horizontally. If it is false, the first tier is vertically arranged.

Parameters:

horizontalFlag - whether to arrange horizontally or vertically.