private void insert1(Point2D p) {
if (contains(p)) return;
boolean newAdded = false;
if (root == null) {
initRoot(p);
} else {
TreeNode curr = root;
while (true) {
if (TreeNode.slightlyEquals(p, curr.value)) {
return;
}
if (curr.even) {
if (p.x() <= curr.value.x()) {
if (curr.left == null) {
TreeNode left = newNode(p, curr);
left.rect =
new RectHV(curr.rect.xmin(), curr.rect.ymin(), curr.value.x(), curr.rect.ymax());
curr.left = left;
break;
} else {
curr = curr.left;
}
} else {
if (curr.right == null) {
TreeNode right = newNode(p, curr);
right.rect =
new RectHV(curr.value.x(), curr.rect.ymin(), curr.rect.xmax(), curr.rect.ymax());
curr.right = right;
break;
} else {
curr = curr.right;
}
}
} else {
if (p.y() < curr.value.y()) {
if (curr.left == null) {
TreeNode left = newNode(p, curr);
left.rect =
new RectHV(curr.rect.xmin(), curr.rect.ymin(), curr.rect.xmax(), curr.value.y());
curr.left = left;
break;
} else {
curr = curr.left;
}
} else {
if (curr.right == null) {
TreeNode right = newNode(p, curr);
right.rect =
new RectHV(curr.rect.xmin(), curr.value.y(), curr.rect.xmax(), curr.rect.ymax());
curr.right = right;
break;
} else {
curr = curr.right;
}
}
}
}
}
size++;
}
private KdNode put(
KdNode nd, Point2D p, int turn, double xmin, double ymin, double xmax, double ymax) {
if (nd == null) {
sz++;
return new KdNode(p, null, null, new RectHV(xmin, ymin, xmax, ymax));
}
// Neglect nodes that collides with one
// Already in the tree
double ndx = nd.point.x();
double ndy = nd.point.y();
if (nd.point.equals(p)) return nd;
else if (turn == 0) {
if (p.x() < ndx) {
nd.left = put(nd.left, p, 1 - turn, xmin, ymin, Math.min(ndx, xmax), ymax);
} else {
nd.right = put(nd.right, p, 1 - turn, Math.max(ndx, xmin), ymin, xmax, ymax);
}
} else {
if (p.y() < ndy) {
nd.left = put(nd.left, p, 1 - turn, xmin, ymin, xmax, Math.min(ndy, ymax));
} else {
nd.right = put(nd.right, p, 1 - turn, xmin, Math.max(ndy, ymin), xmax, ymax);
}
}
return nd;
}
public boolean insert(Point2D p) {
if (p.equals(value)) {
return false;
}
if (onLeft(p)) {
if (left == null) {
final TreeNode treeNode = newNode(p, this);
treeNode.rect =
even
? new RectHV(rect.xmin(), rect.ymin(), value.x(), rect.ymax())
: new RectHV(rect.xmin(), rect.ymin(), rect.xmax(), value.y());
left = treeNode;
return true;
} else {
return left.insert(p);
}
} else if (onRight(p)) {
if (right == null) {
TreeNode treeNode = newNode(p, this);
treeNode.rect =
even
? new RectHV(rect.xmin(), value.y(), rect.xmax(), rect.ymax())
: new RectHV(rect.xmin(), value.y(), rect.xmax(), rect.ymax());
right = treeNode;
return true;
} else {
return right.insert(p);
}
}
return false;
}
private int compare(Point2D p, Point2D q, Orientation orientation) {
if (orientation == Orientation.LR) {
return Double.compare(p.x(), q.x());
} else {
return Double.compare(p.y(), q.y());
}
}
private boolean onTheRight(final Point2D point, final Point2D current, final boolean vertical) {
if (vertical) {
return point.x() >= current.x();
} else {
return point.y() >= current.y();
}
}
private double distanceToVertical(final Point2D p, final Point2D v, final boolean vertical) {
if (vertical) {
return Math.abs(p.x() - v.x());
} else {
return Math.abs(p.y() - v.y());
}
}
private boolean onTheRight(final Point2D point, final RectHV rect, final boolean vertical) {
if (vertical) {
return rect.xmin() > point.x();
} else {
return rect.ymin() > point.y();
}
}
private boolean onTheLeft(final Point2D point, final RectHV rect, final boolean vertical) {
if (vertical) {
return rect.xmax() < point.x();
} else {
return rect.ymax() < point.y();
}
}
private boolean search(KdNode nd, Point2D p, int turn) {
if (nd == null) return false;
if (nd.point.equals(p)) {
return true;
} else if (turn == 0) {
if (p.x() < nd.point.x()) return search(nd.left, p, 1 - turn);
else return search(nd.right, p, 1 - turn);
} else {
if (p.y() < nd.point.y()) return search(nd.left, p, 1 - turn);
else return search(nd.right, p, 1 - turn);
}
}
// a nearest neighbor in the set to point p; null if the set is empty
public Point2D nearest(Point2D p) {
if (p == null) throw new NullPointerException("point");
Point2D nearestPoint = null;
double nearestDist = MAX_DISTANCE;
for (Point2D currPoint : points) {
double currDist = currPoint.distanceTo(p);
if (currDist < nearestDist) {
nearestDist = currDist;
nearestPoint = currPoint;
}
}
return nearestPoint;
}
private Point2D findNearest(
Node x, Point2D p, Point2D nearest, double minDist, Orientation orientation) {
if (x == null) {
return nearest;
}
Point2D closest = nearest;
double closestDistance = minDist;
double distance = x.p.distanceSquaredTo(p);
if (distance < minDist) {
closest = x.p;
closestDistance = distance;
}
Node first, second;
if (orientation == Orientation.LR) {
if (p.x() < x.p.x()) {
first = x.lb;
second = x.rt;
} else {
first = x.rt;
second = x.lb;
}
} else {
if (p.y() < x.p.y()) {
first = x.lb;
second = x.rt;
} else {
first = x.rt;
second = x.lb;
}
}
Orientation nextOrientation = orientation.next();
if (first != null && first.rect.distanceSquaredTo(p) < closestDistance) {
closest = findNearest(first, p, closest, closestDistance, nextOrientation);
closestDistance = closest.distanceSquaredTo(p);
}
if (second != null && second.rect.distanceSquaredTo(p) < closestDistance) {
closest = findNearest(second, p, closest, closestDistance, nextOrientation);
}
return closest;
}
public boolean contains(Point2D p) {
if (p.equals(value)) {
return true;
} else if (onLeft(p)) {
return left != null && left.contains(p);
} else if (onRight(p)) {
return right != null && right.contains(p);
} else {
System.out.println("Impossible!");
return false;
}
}
private Node put(final Node x, final Point2D key, final boolean vertical) {
if (x == null) {
return new Node(key, 1);
}
double cmp;
if (vertical) {
cmp = key.x() - x.key.x();
} else {
cmp = key.y() - x.key.y();
}
if (key.equals(x.key)) {
// do nothing
} else if (cmp <= 0) {
x.left = put(x.left, key, !vertical);
x.N = 1 + size(x.left) + size(x.right);
} else if (cmp > 0) {
x.right = put(x.right, key, !vertical);
x.N = 1 + size(x.left) + size(x.right);
}
return x;
}
private Point2D get(final Node x, final Point2D key, final boolean vertical) {
if (x == null) {
return null;
}
if (x.key.equals(key)) {
return x.key;
}
double cmp;
if (vertical) {
cmp = key.x() - x.key.x();
} else {
cmp = key.y() - x.key.y();
}
if (cmp <= 0) {
return get(x.left, key, !vertical);
} else {
return get(x.right, key, !vertical);
}
}
public Point2D nearest(Point2D p, Point2D nearest) {
if (slightlyEquals(p, nearest)) return nearest;
double minDistance = p.distanceSquaredTo(nearest);
if (left != null) {
final double distanceTo = p.distanceTo(left.value);
if (distanceTo <= minDistance) {
minDistance = distanceTo;
nearest = left.value;
}
}
if (right != null) {
final double distanceTo = p.distanceTo(right.value);
if (distanceTo <= minDistance) {
minDistance = distanceTo;
nearest = right.value;
}
}
Point2D lnearest = nearest;
if (left != null && left.rect.distanceTo(nearest) < minDistance) {
lnearest = left.nearest(p, nearest);
}
Point2D rnearest = nearest;
if (right != null && right.rect.distanceTo(nearest) < minDistance) {
rnearest = right.nearest(p, nearest);
}
final double ldist = p.distanceTo(lnearest);
final double rdist = p.distanceTo(rnearest);
if (ldist < minDistance) {
nearest = lnearest;
minDistance = ldist;
}
if (rdist < minDistance) {
nearest = rnearest;
minDistance = rdist;
}
return nearest;
}
// a nearest neighbor in the set to point p; null if the set is empty
public Point2D nearest(Point2D p) {
if (p == null) throw new NullPointerException("Point2D cannot be null!");
if (set.isEmpty()) return null;
double minDistance = Double.MAX_VALUE;
Point2D minPoint = null;
for (Point2D point : set) {
double distance = p.distanceSquaredTo(point);
if (distance < minDistance) {
minDistance = distance;
minPoint = point;
}
}
return minPoint;
}
private void nearest(
final Node node, final Holder<Point2D> nearest, final Point2D p, final boolean vertical) {
if (node == null) {
return;
} else if (node.key.compareTo(p) == 0) {
nearest.value = node.key;
return;
} else if (p.distanceTo(node.key) < p.distanceTo(nearest.value)) {
nearest.value = node.key;
}
if (onTheLeft(p, node.key, vertical)) {
nearest(node.left, nearest, p, !vertical);
if (distanceToVertical(p, node.key, vertical) < p.distanceTo(nearest.value)) {
nearest(node.right, nearest, p, !vertical);
}
} else if (onTheRight(p, node.key, vertical)) {
nearest(node.right, nearest, p, !vertical);
if (distanceToVertical(p, node.key, vertical) < p.distanceTo(nearest.value)) {
nearest(node.left, nearest, p, !vertical);
}
}
}
public Point2D ceiling(Point2D p, boolean inclusive) {
requireNonNull(p);
if (value.equals(p)) {
return value;
} else if (onRight(p)) {
if (right != null && right.onLeft(p)) {
return inclusive ? value : right.value;
} else if (right != null && right.onRight(p)) {
return right.ceiling(p, inclusive);
} else {
return inclusive ? value : null;
}
} else if (onLeft(p)) {
return left == null ? inclusive ? null : value : left.ceiling(p, inclusive);
} else {
return inclusive ? value : null;
}
}
// draw all points to standard draw
public void draw() {
for (Point2D point2D : root.subSet(LOWER, HIGHER)) {
StdDraw.point(point2D.x(), point2D.y());
}
}
private Point2D find(KdNode nd, double curDist, Point2D target, int turn) {
Point2D curClosest = null;
if (nd == null) return curClosest;
// Pruning
if (nd.rect.distanceTo(target) > curDist) {
return null;
}
if (nd.point.distanceTo(target) < curDist) {
curClosest = nd.point;
curDist = nd.point.distanceTo(target);
}
// Always search the plane that target is on according to
// current node
if ((turn == 0 && target.x() < nd.point.x()) || (turn == 1 && target.y() < nd.point.y())) {
Point2D left = find(nd.left, curDist, target, 1 - turn);
if (left != null && left.distanceTo(target) < curDist) {
curClosest = left;
curDist = left.distanceTo(target);
}
Point2D right = find(nd.right, curDist, target, 1 - turn);
if (right != null && right.distanceTo(target) < curDist) {
curClosest = right;
curDist = right.distanceTo(target);
}
} else {
Point2D right = find(nd.right, curDist, target, 1 - turn);
if (right != null && right.distanceTo(target) < curDist) {
curClosest = right;
curDist = right.distanceTo(target);
}
Point2D left = find(nd.left, curDist, target, 1 - turn);
if (left != null && left.distanceTo(target) < curDist) {
curClosest = left;
curDist = left.distanceTo(target);
}
}
return curClosest;
}
public static void main(String[] args) {
String filename = args[0];
In in = new In(filename);
StdDraw.show(0);
// initialize the data structures with N points from standard input
PointSET brute = new PointSET();
KdTree kdtree = new KdTree();
while (!in.isEmpty()) {
double x = in.readDouble();
double y = in.readDouble();
Point2D p = new Point2D(x, y);
kdtree.insert(p);
brute.insert(p);
}
double x0 = 0.0, y0 = 0.0; // initial endpoint of rectangle
double x1 = 0.0, y1 = 0.0; // current location of mouse
boolean isDragging = false; // is the user dragging a rectangle
// draw the points
StdDraw.clear();
StdDraw.setPenColor(StdDraw.BLACK);
StdDraw.setPenRadius(.01);
brute.draw();
while (true) {
StdDraw.show(40);
// user starts to drag a rectangle
if (StdDraw.mousePressed() && !isDragging) {
x0 = StdDraw.mouseX();
y0 = StdDraw.mouseY();
isDragging = true;
continue;
}
// user is dragging a rectangle
else if (StdDraw.mousePressed() && isDragging) {
x1 = StdDraw.mouseX();
y1 = StdDraw.mouseY();
continue;
}
// mouse no longer pressed
else if (!StdDraw.mousePressed() && isDragging) {
isDragging = false;
}
RectHV rect =
new RectHV(Math.min(x0, x1), Math.min(y0, y1), Math.max(x0, x1), Math.max(y0, y1));
// draw the points
StdDraw.clear();
StdDraw.setPenColor(StdDraw.BLACK);
StdDraw.setPenRadius(.01);
brute.draw();
// draw the rectangle
StdDraw.setPenColor(StdDraw.BLACK);
StdDraw.setPenRadius();
rect.draw();
// draw the range search results for brute-force data structure in
// red
StdDraw.setPenRadius(.03);
StdDraw.setPenColor(StdDraw.RED);
for (Point2D p : brute.range(rect)) p.draw();
// draw the range search results for kd-tree in blue
StdDraw.setPenRadius(.02);
StdDraw.setPenColor(StdDraw.BLUE);
for (Point2D p : kdtree.range(rect)) p.draw();
StdDraw.show(40);
}
}
private static boolean slightlyEquals(Point2D p1, Point2D p2) {
return Math.abs(p1.x() - p2.x()) < 0.000001 && Math.abs(p1.y() - p2.y()) < 0.000001;
}
// draw all points to standard draw
public void draw() {
for (Point2D point : points) {
point.draw();
}
}
// draw all points to standard draw
public void draw() {
for (Point2D point : set) {
point.draw();
}
}
private double distanceTo(Point2D p1, Point2D p2) {
if (p2 == null) return Double.MAX_VALUE;
return p1.distanceTo(p2);
}
private boolean onRight(final Point2D p) {
return (even && (p.x() > value.x())) || (!even && (p.y() > value.y()));
}
private boolean onLeft(final Point2D p) {
return (even && (p.x() <= value.x())) || (!even && (p.y() <= value.y()));
}