public static void removeEdgesInOrderFromOuterBoundary(VHalfEdge _outeredge, int length_cutoff) {
// Collect a list of outer edges
OrderedEdgeList outeredges = new OrderedEdgeList(_outeredge);
// System.out.println();
// System.out.println("************************************************");
// System.out.println("*** removeEdgesInOrderFromOuterBoundary()");
// Remove edges until we can't remove any more
boolean haschanged;
int edgesremoved = 0;
do {
haschanged = false;
Iterator<VHalfEdge> iter = outeredges.values().iterator();
while (iter.hasNext()) {
VHalfEdge edge = iter.next();
// System.out.println("Considering removal of edge (" + edge.vertex.id + "," +
// edge.getConnectedVertex().id + ") - length=" + edge.getLength());
// Return if the length of the given edge is less than or equal to
// the minimum value allowed (i.e. the cut-off value)
if (edge.getLength() <= length_cutoff) {
return;
}
// Cannot remove if removal would leave only _one_ edge
// left coming from the given vertex.
if (edge.vertex.getEdges().size() <= 2
|| edge.getConnectedVertex().getEdges().size() <= 2) {
// System.out.println("Irregular");
continue;
}
// Cannot remove if removal would leave a _point_ where
// _two shapes_ are connected
VHalfEdge inneredge = edge.getConnectedVertex().getEdge(edge.vertex);
VVertex innertriangletopvertex = inneredge.next.getConnectedVertex();
if (innertriangletopvertex.getEdge(TriangulationRepresentation.OUTER_VERTEXNUMBER)
!= null) {
// System.out.println("Irregular");
continue;
}
// Remove the edge if it's valid to do so
iter.remove();
edgesremoved++;
removeSingleOuterEdge(edge, outeredges);
haschanged = true;
break;
}
} while ((haschanged)
&& (TriangulationRepresentation.MAX_EDGES_TO_REMOVE < 0
|| edgesremoved < TriangulationRepresentation.MAX_EDGES_TO_REMOVE));
}
public int compare(VHalfEdge e1, VHalfEdge e2) {
if (e1.getLength() > e2.getLength()) return -1;
else if (e1.getLength() < e2.getLength()) return 1;
else {
// Note: duplicates are removed from the TreeMap that uses
// this comparator - so we really don't want to edges to
// be considered identical (not specified in java documentation)
if (e1.getY() < e2.getY()) return -1;
else if (e1.getY() > e2.getY()) return 1;
else if (e1.getX() < e2.getX()) return -1;
else if (e1.getX() > e2.getX()) return 1;
else return 0;
}
}
private static void removeSingleOuterEdge(VHalfEdge outeredge, OrderedEdgeList outeredges) {
// System.out.println("Removing edge (" + outeredge.vertex.id + "," +
// outeredge.getConnectedVertex().id + ")");
// Get inner halfedge
VHalfEdge inneredge = outeredge.getConnectedVertex().getEdge(outeredge.vertex);
// System.out.println(" - Got inner edge (" + inneredge.vertex.id + "," +
// inneredge.getConnectedVertex().id + ")");
// Remove halfedges (both inner and outer)
// System.out.println(" - Removing both inner and outer edge");
if (outeredge.vertex.removeEdge(outeredge) == false) {
throw new RuntimeException("Outer edge not removed successfully");
}
if (inneredge.vertex.removeEdge(inneredge) == false) {
throw new RuntimeException("Inner edge not removed successfully");
}
// Get previous edge
VHalfEdge previousedge = null;
// System.out.println(" - Determining previous edge");
for (VHalfEdge tmpedge : outeredge.vertex.getEdges()) {
// System.out.println(" + Considering (" + tmpedge.vertex.id + "," + tmpedge.next.vertex.id
// + ")");
VHalfEdge tmppreviousedge =
tmpedge.getConnectedVertex().getEdge(TriangulationRepresentation.OUTER_VERTEXNUMBER);
if (tmppreviousedge != null && tmppreviousedge.next == outeredge) {
previousedge = tmppreviousedge;
break;
}
}
if (previousedge == null) {
throw new RuntimeException("Previous edge was null");
}
// System.out.println(" - Found Previous Edge (" + previousedge.vertex.id + "," +
// previousedge.next.vertex.id + ")");
// Relink and relabel nodes appropriately
VHalfEdge newouteredge = inneredge.next;
// System.out.println(" - Set Previous Edge Next to Vertex " + newouteredge.vertex.id);
previousedge.next = newouteredge;
do {
// System.out.println(" + Set Edge (" + newouteredge.vertex.id + "," +
// newouteredge.next.vertex.id + ") as Outer Edge");
outeredges.addEdge(newouteredge);
newouteredge.vertexnumber = TriangulationRepresentation.OUTER_VERTEXNUMBER;
} while ((newouteredge = newouteredge.next).next != inneredge);
outeredges.addEdge(newouteredge);
newouteredge.vertexnumber = TriangulationRepresentation.OUTER_VERTEXNUMBER;
newouteredge.next = outeredge.next;
// System.out.println(" - Set Edge (" + newouteredge.vertex.id + "," +
// newouteredge.next.vertex.id + ") as Outer Edge and to point to Edge (" +
// outeredge.next.vertex.id + "," + outeredge.next.next.vertex.id + ")");
// Reset previous edges details
inneredge.vertexnumber = outeredge.vertexnumber = -99;
// inneredge.vertex = outeredge.vertex = null;
inneredge.next = outeredge.next = null;
}