/** {@inheritDoc} */
public void process(final LGraph layeredGraph, final IElkProgressMonitor monitor) {
monitor.begin("End label placement", 1);
double labelSpacing = layeredGraph.getProperty(LayeredOptions.SPACING_EDGE_LABEL);
// Initialize the offset maps
northOffset = Maps.newHashMap();
southOffset = Maps.newHashMap();
portLabelOffsetHint = Maps.newHashMap();
for (Layer layer : layeredGraph.getLayers()) {
for (LNode node : layer.getNodes()) {
for (LEdge edge : node.getOutgoingEdges()) {
for (LLabel label : edge.getLabels()) {
// Only consider end labels
if (label.getProperty(LayeredOptions.EDGE_LABELS_PLACEMENT) == EdgeLabelPlacement.TAIL
|| label.getProperty(LayeredOptions.EDGE_LABELS_PLACEMENT)
== EdgeLabelPlacement.HEAD) {
placeEndLabel(node, edge, label, labelSpacing);
}
}
}
}
}
monitor.done();
}
/**
* Places the given end label of the given edge starting at the given node.
*
* @param node source node of the edge.
* @param edge the edge whose end label to place.
* @param label the end label to place.
* @param labelSpacing space between objects and labels.
*/
private void placeEndLabel(
final LNode node, final LEdge edge, final LLabel label, final double labelSpacing) {
// Get the nearest port (source port for tail labels, target port for head labels)
LPort port = null;
if (label.getProperty(LayeredOptions.EDGE_LABELS_PLACEMENT) == EdgeLabelPlacement.TAIL) {
port = edge.getSource();
} else if (label.getProperty(LayeredOptions.EDGE_LABELS_PLACEMENT) == EdgeLabelPlacement.HEAD) {
port = edge.getTarget();
}
// Initialize offset with zero if no offset was present
if (!northOffset.containsKey(port.getNode())) {
northOffset.put(port.getNode(), 0.0);
}
if (!southOffset.containsKey(port.getNode())) {
southOffset.put(port.getNode(), 0.0);
}
if (!portLabelOffsetHint.containsKey(port)) {
portLabelOffsetHint.put(port, 0.0);
}
// Calculate end label position based on side choice
// Port side undefined can be left out, because there would be no reasonable
// way of handling them
if (label.getProperty(InternalProperties.LABEL_SIDE) == LabelSide.ABOVE) {
placeEndLabelUpwards(node, label, port, labelSpacing);
} else {
placeEndLabelDownwards(node, label, port, labelSpacing);
}
}