/** Paints the <tt>visualEdge</tt>. No arrowhead is drawn. */
public void paint(VisualGraphComponent component, Graphics2D g2d) {
VisualEdge vEdge = (VisualEdge) component;
Rectangle fromvertexBounds;
Rectangle tovertexBounds;
GeneralPath drawPath;
VisualVertex visualVertexA = vEdge.getVisualVertexA();
VisualVertex visualVertexB = vEdge.getVisualVertexB();
GraphLayoutManager layoutmanager = vEdge.getVisualGraph().getGraphLayoutManager();
drawPath = vEdge.getGeneralPath();
// If there is no layoutmanager or there is one but the layout has not
// been initialised, by default, let us route edges as straight lines.
if (layoutmanager == null || (layoutmanager != null && !layoutmanager.isInitialized())) {
fromvertexBounds = visualVertexA.getBounds();
tovertexBounds = visualVertexB.getBounds();
// Make sure to clear the GeneralPath() first. Otherwise, the edge's previous
// path will be redrawn as well.
drawPath.reset();
// Start the line from the center of the vEdgertex
drawPath.moveTo((float) fromvertexBounds.getCenterX(), (float) fromvertexBounds.getCenterY());
drawPath.lineTo((float) tovertexBounds.getCenterX(), (float) tovertexBounds.getCenterY());
} else {
// Let the layout manager determine how the edge will be routed.
layoutmanager.routeEdge(g2d, vEdge);
}
// Draw the line
g2d.setColor(vEdge.getOutlinecolor());
g2d.draw(drawPath);
// Draw the edge label
this.paintText(vEdge, g2d);
}
/**
* Wrapper method around the <tt>paintText()</tt> method of the <tt>VisualEdgePainter</tt>
* interface. This method performs the calculation to determine the position where the text will
* be drawn.
*/
private void paintText(VisualEdge vEdge, Graphics2D g2d) {
Point fromPoint = new Point();
Point toPoint = new Point();
GeneralPath gPath = vEdge.getGeneralPath();
PathIterator iterator = gPath.getPathIterator(null);
FontMetrics fontMetrics;
float edgeSegment[] = new float[6];
double currentLength = 0;
float cumulativeLength = 0;
float x1 = 0, y1 = 0, x2 = 0, y2 = 0;
int segmentType;
boolean firstPointInitialized = false;
// Get the total length of the edge
float edgeLength = vEdge.getEdgeLength(vEdge, fromPoint, toPoint);
while (!iterator.isDone()) {
segmentType = iterator.currentSegment(edgeSegment);
switch (segmentType) {
case PathIterator.SEG_LINETO:
case PathIterator.SEG_MOVETO:
x2 = edgeSegment[0];
y2 = edgeSegment[1];
break;
case PathIterator.SEG_QUADTO:
x2 = edgeSegment[2];
y2 = edgeSegment[3];
break;
case PathIterator.SEG_CUBICTO:
x2 = edgeSegment[4];
y2 = edgeSegment[5];
}
if (firstPointInitialized) {
currentLength = Point2D.distance(x1, y1, x2, y2);
cumulativeLength += currentLength;
}
iterator.next();
// If we are halfway through the length of the edge,
// then paint the text
if (cumulativeLength >= (edgeLength / 2) || cumulativeLength >= edgeLength) {
// Ratio of the remaining half-length over the length of the current edge
double ratio = ((edgeLength / 2) - (cumulativeLength - currentLength)) / currentLength;
fontMetrics = vEdge.getFontMetrics();
// Take into account the text's length
this.paintText(
g2d,
vEdge.getFont(),
vEdge.getFontcolor(),
vEdge.getLabel(),
(float)
(fromPoint.getX() < toPoint.getX()
? (x1 + (Math.abs(x2 - x1) * ratio))
: (x1 - (Math.abs(x2 - x1) * ratio)))
- fontMetrics.stringWidth(vEdge.getLabel()) / 2,
(float)
(fromPoint.getY() < toPoint.getY()
? (y1 + (Math.abs(y2 - y1) * ratio))
: (y1 - (Math.abs(y2 - y1) * ratio))));
break;
}
x1 = x2;
y1 = y2;
if (!firstPointInitialized) {
firstPointInitialized = true;
}
}
}