/**
* Inserted edges are checked to see if an identical edge already exists. If so, the edge is not
* inserted, but its label is merged with the existing edge.
*/
protected void insertUniqueEdge(Edge e) {
// <FIX> MD 8 Oct 03 speed up identical edge lookup
// fast lookup
Edge existingEdge = edgeList.findEqualEdge(e);
// If an identical edge already exists, simply update its label
if (existingEdge != null) {
Label existingLabel = existingEdge.getLabel();
Label labelToMerge = e.getLabel();
// check if new edge is in reverse direction to existing edge
// if so, must flip the label before merging it
if (!existingEdge.isPointwiseEqual(e)) {
labelToMerge = new Label(e.getLabel());
labelToMerge.flip();
}
existingLabel.merge(labelToMerge);
// compute new depth delta of sum of edges
int mergeDelta = depthDelta(labelToMerge);
int existingDelta = existingEdge.getDepthDelta();
int newDelta = existingDelta + mergeDelta;
existingEdge.setDepthDelta(newDelta);
} else { // no matching existing edge was found
// add this new edge to the list of edges in this graph
// e.setName(name + edges.size());
edgeList.add(e);
e.setDepthDelta(depthDelta(e.getLabel()));
}
}
public Geometry buffer(Geometry g, double distance) {
PrecisionModel precisionModel = workingPrecisionModel;
if (precisionModel == null) precisionModel = g.getPrecisionModel();
// factory must be the same as the one used by the input
geomFact = g.getFactory();
OffsetCurveBuilder curveBuilder = new OffsetCurveBuilder(precisionModel, bufParams);
OffsetCurveSetBuilder curveSetBuilder = new OffsetCurveSetBuilder(g, distance, curveBuilder);
List bufferSegStrList = curveSetBuilder.getCurves();
// short-circuit test
if (bufferSegStrList.size() <= 0) {
return createEmptyResultGeometry();
}
// BufferDebug.runCount++;
// String filename = "run" + BufferDebug.runCount + "_curves";
// System.out.println("saving " + filename);
// BufferDebug.saveEdges(bufferEdgeList, filename);
// DEBUGGING ONLY
// WKTWriter wktWriter = new WKTWriter();
// Debug.println("Rings: " + wktWriter.write(convertSegStrings(bufferSegStrList.iterator())));
// wktWriter.setMaxCoordinatesPerLine(10);
// System.out.println(wktWriter.writeFormatted(convertSegStrings(bufferSegStrList.iterator())));
computeNodedEdges(bufferSegStrList, precisionModel);
graph = new PlanarGraph(new OverlayNodeFactory());
graph.addEdges(edgeList.getEdges());
List subgraphList = createSubgraphs(graph);
PolygonBuilder polyBuilder = new PolygonBuilder(geomFact);
buildSubgraphs(subgraphList, polyBuilder);
List resultPolyList = polyBuilder.getPolygons();
// just in case...
if (resultPolyList.size() <= 0) {
return createEmptyResultGeometry();
}
Geometry resultGeom = geomFact.buildGeometry(resultPolyList);
return resultGeom;
}