/*
* Copyright (c) 2005, the JUNG Project and the Regents of the University of
* California All rights reserved.
*
* This software is open-source under the BSD license; see either "license.txt"
* or http://jung.sourceforge.net/license.txt for a description.
*
* Created on Aug 23, 2005
*/
package edu.uci.ics.jung.visualization.renderers;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import edu.uci.ics.jung.visualization.RenderContext;
public class BasicEdgeArrowRenderingSupport<V,E> implements EdgeArrowRenderingSupport<V, E> {
/* (non-Javadoc)
* @see edu.uci.ics.jung.visualization.renderers.EdgeArrowRenderingSupport#getArrowTransform(edu.uci.ics.jung.visualization.RenderContext, java.awt.geom.GeneralPath, java.awt.Shape)
*/
public AffineTransform getArrowTransform(RenderContext<V,E> rc, Shape edgeShape, Shape vertexShape) {
GeneralPath path = new GeneralPath(edgeShape);
float[] seg = new float[6];
Point2D p1=null;
Point2D p2=null;
AffineTransform at = new AffineTransform();
// when the PathIterator is done, switch to the line-subdivide
// method to get the arrowhead closer.
for(PathIterator i=path.getPathIterator(null,1); !i.isDone(); i.next()) {
int ret = i.currentSegment(seg);
if(ret == PathIterator.SEG_MOVETO) {
p2 = new Point2D.Float(seg[0],seg[1]);
} else if(ret == PathIterator.SEG_LINETO) {
p1 = p2;
p2 = new Point2D.Float(seg[0],seg[1]);
if(vertexShape.contains(p2)) {
at = getArrowTransform(rc, new Line2D.Float(p1,p2),vertexShape);
break;
}
}
}
return at;
}
/* (non-Javadoc)
* @see edu.uci.ics.jung.visualization.renderers.EdgeArrowRenderingSupport#getReverseArrowTransform(edu.uci.ics.jung.visualization.RenderContext, java.awt.geom.GeneralPath, java.awt.Shape)
*/
public AffineTransform getReverseArrowTransform(RenderContext<V,E> rc, Shape edgeShape, Shape vertexShape) {
return getReverseArrowTransform(rc, edgeShape, vertexShape, true);
}
/* (non-Javadoc)
* @see edu.uci.ics.jung.visualization.renderers.EdgeArrowRenderingSupport#getReverseArrowTransform(edu.uci.ics.jung.visualization.RenderContext, java.awt.geom.GeneralPath, java.awt.Shape, boolean)
*/
public AffineTransform getReverseArrowTransform(RenderContext<V,E> rc, Shape edgeShape, Shape vertexShape,
boolean passedGo) {
GeneralPath path = new GeneralPath(edgeShape);
float[] seg = new float[6];
Point2D p1=null;
Point2D p2=null;
AffineTransform at = new AffineTransform();
for(PathIterator i=path.getPathIterator(null,1); !i.isDone(); i.next()) {
int ret = i.currentSegment(seg);
if(ret == PathIterator.SEG_MOVETO) {
p2 = new Point2D.Float(seg[0],seg[1]);
} else if(ret == PathIterator.SEG_LINETO) {
p1 = p2;
p2 = new Point2D.Float(seg[0],seg[1]);
if(passedGo == false && vertexShape.contains(p2)) {
passedGo = true;
} else if(passedGo==true &&
vertexShape.contains(p2)==false) {
at = getReverseArrowTransform(rc, new Line2D.Float(p1,p2),vertexShape);
break;
}
}
}
return at;
}
/* (non-Javadoc)
* @see edu.uci.ics.jung.visualization.renderers.EdgeArrowRenderingSupport#getArrowTransform(edu.uci.ics.jung.visualization.RenderContext, java.awt.geom.Line2D, java.awt.Shape)
*/
public AffineTransform getArrowTransform(RenderContext<V,E> rc, Line2D edgeShape, Shape vertexShape) {
float dx = (float) (edgeShape.getX1()-edgeShape.getX2());
float dy = (float) (edgeShape.getY1()-edgeShape.getY2());
// iterate over the line until the edge shape will place the
// arrowhead closer than 'arrowGap' to the vertex shape boundary
while((dx*dx+dy*dy) > rc.getArrowPlacementTolerance()) {
try {
edgeShape = getLastOutsideSegment(edgeShape, vertexShape);
} catch(IllegalArgumentException e) {
System.err.println(e.toString());
return null;
}
dx = (float) (edgeShape.getX1()-edgeShape.getX2());
dy = (float) (edgeShape.getY1()-edgeShape.getY2());
}
double atheta = Math.atan2(dx,dy)+Math.PI/2;
AffineTransform at =
AffineTransform.getTranslateInstance(edgeShape.getX1(), edgeShape.getY1());
at.rotate(-atheta);
return at;
}
/**
* This is used for the reverse-arrow of a non-directed edge
* get a transform to place the arrow shape on the passed edge at the
* point where it intersects the passed shape
* @param edgeShape
* @param vertexShape
* @return
*/
protected AffineTransform getReverseArrowTransform(RenderContext<V,E> rc, Line2D edgeShape, Shape vertexShape) {
float dx = (float) (edgeShape.getX1()-edgeShape.getX2());
float dy = (float) (edgeShape.getY1()-edgeShape.getY2());
// iterate over the line until the edge shape will place the
// arrowhead closer than 'arrowGap' to the vertex shape boundary
while((dx*dx+dy*dy) > rc.getArrowPlacementTolerance()) {
try {
edgeShape = getFirstOutsideSegment(edgeShape, vertexShape);
} catch(IllegalArgumentException e) {
System.err.println(e.toString());
return null;
}
dx = (float) (edgeShape.getX1()-edgeShape.getX2());
dy = (float) (edgeShape.getY1()-edgeShape.getY2());
}
// calculate the angle for the arrowhead
double atheta = Math.atan2(dx,dy)-Math.PI/2;
AffineTransform at = AffineTransform.getTranslateInstance(edgeShape.getX1(),edgeShape.getY1());
at.rotate(-atheta);
return at;
}
/**
* Passed Line's point2 must be inside the passed shape or
* an IllegalArgumentException is thrown
* @param line line to subdivide
* @param shape shape to compare with line
* @return a line that intersects the shape boundary
* @throws IllegalArgumentException if the passed line's point1 is not inside the shape
*/
protected Line2D getLastOutsideSegment(Line2D line, Shape shape) {
if(shape.contains(line.getP2())==false) {
String errorString =
"line end point: "+line.getP2()+" is not contained in shape: "+shape.getBounds2D();
throw new IllegalArgumentException(errorString);
//return null;
}
Line2D left = new Line2D.Double();
Line2D right = new Line2D.Double();
// subdivide the line until its left segment intersects
// the shape boundary
do {
subdivide(line, left, right);
line = right;
} while(shape.contains(line.getP1())==false);
// now that right is completely inside shape,
// return left, which must be partially outside
return left;
}
/**
* Passed Line's point1 must be inside the passed shape or
* an IllegalArgumentException is thrown
* @param line line to subdivide
* @param shape shape to compare with line
* @return a line that intersects the shape boundary
* @throws IllegalArgumentException if the passed line's point1 is not inside the shape
*/
protected Line2D getFirstOutsideSegment(Line2D line, Shape shape) {
if(shape.contains(line.getP1())==false) {
String errorString =
"line start point: "+line.getP1()+" is not contained in shape: "+shape.getBounds2D();
throw new IllegalArgumentException(errorString);
}
Line2D left = new Line2D.Float();
Line2D right = new Line2D.Float();
// subdivide the line until its right side intersects the
// shape boundary
do {
subdivide(line, left, right);
line = left;
} while(shape.contains(line.getP2())==false);
// now that left is completely inside shape,
// return right, which must be partially outside
return right;
}
/**
* divide a Line2D into 2 new Line2Ds that are returned
* in the passed left and right instances, if non-null
* @param src the line to divide
* @param left the left side, or null
* @param right the right side, or null
*/
protected void subdivide(Line2D src,
Line2D left,
Line2D right) {
double x1 = src.getX1();
double y1 = src.getY1();
double x2 = src.getX2();
double y2 = src.getY2();
double mx = x1 + (x2-x1)/2.0;
double my = y1 + (y2-y1)/2.0;
if (left != null) {
left.setLine(x1, y1, mx, my);
}
if (right != null) {
right.setLine(mx, my, x2, y2);
}
}
}