Język: Java
Wynik: 555 533
Po prostu poszedłem za próbą rozwiązania brutalnej siły przez iterację kształtów w kolejności malejącej powierzchni (obwód w przypadku wiązania) i wypróbowanie wszystkich możliwości pakowania, aż do znalezienia prawidłowego pakowania dla tego kształtu, w którym to miejscu pozycja kształtu jest ustalona i algorytm przechodzi do następnego kształtu. Aby, miejmy nadzieję, poprawić jakość wyniku przy poszukiwaniu prawidłowego opakowania, najpierw wypróbowuje się wszystkie możliwe pozycje z obróconym kształtem, tak aby był on wyższy niż szerszy.
Uwaga: zakłada się, że obrazy wejściowe mają wszystkie kształty oddzielone białą spacją. Przyjmuje maksymalną szerokość wyniku jako pierwszy argument i listę obrazów kształtów jako pozostałych argumentów (każdy obraz kształtu może mieć jeden lub więcej kształtów oddzielonych co najmniej jedną linią białych pikseli)
import java.awt.Color;
import java.awt.Graphics;
import java.awt.geom.AffineTransform;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import javax.imageio.ImageIO;
public class Packer {
public static void main(String[] args) throws Exception {
long t1 = System.currentTimeMillis();
int width = Integer.valueOf(args[0]);
List<Item> itemList = new ArrayList<Item>();
for (int i = 1; i < args.length; i++) {
itemList.addAll(getItems(ImageIO.read(new File(args[i]))));
}
File outputFile = new File("output.png");
if (outputFile.exists()) {
outputFile.delete();
}
outputFile.createNewFile();
ImageIO.write(pack(itemList, width), "PNG", outputFile);
long t2 = System.currentTimeMillis();
System.out.println("Finished in " + (t2 - t1) + "ms");
}
private static BufferedImage pack(List<Item> itemList, int width) {
System.out.println("Packing " + itemList.size() + " items");
Collections.sort(itemList, new Comparator<Item>() {
@Override
public int compare(Item o1, Item o2) {
return o1.area < o2.area ? 1 : (o1.area > o2.area ? -1
: (o1.perimiter < o2.perimiter ? 1
: (o1.perimiter > o2.perimiter ? -1 : 0)));
}
});
Packing packing = new Packing(width);
PackedItem.Rotation[] widthRots = { PackedItem.Rotation.ZERO,
PackedItem.Rotation.ONE_EIGHTY };
PackedItem.Rotation[] heightRots = { PackedItem.Rotation.NINETY,
PackedItem.Rotation.TWO_SEVENTY };
int count = 0;
for (Item item : itemList) {
count++;
int minSize = Math.min(item.width, item.height);
int maxSize = Math.max(item.width, item.height);
int x = 0;
int y = 0;
int rot = 0;
PackedItem.Rotation[] rots = widthRots;
if (item.width > item.height) {
rots = heightRots;
}
boolean rotsSwitched = false;
PackedItem packedItem = new PackedItem(item, rots[rot], x, y);
System.out.format("Packing item %d which is %d by %d\n", count,
item.width, item.height);
while (!packing.isValidWith(packedItem)) {
if (rot == 0) {
rot = 1;
} else {
rot = 0;
if (x + minSize >= width) {
x = 0;
y++;
if (!rotsSwitched
&& y + maxSize > packing.height) {
rotsSwitched = true;
if (item.width > item.height) {
rots = widthRots;
} else {
rots = heightRots;
}
y = 0;
}
} else {
x++;
}
}
packedItem.set(x, y, rots[rot]);
}
packing.addItem(packedItem);
System.out.format("Packed item %d\n", count);
}
return packing.getDrawing();
}
private static List<Item> getItems(BufferedImage image) {
List<Item> itemList = new ArrayList<Item>();
boolean[][] pointsProcessed = new boolean[image.getWidth()][image
.getHeight()];
for (int i = 0; i < image.getWidth(); i++) {
for (int j = 0; j < image.getHeight(); j++) {
if (pointsProcessed[i][j]) {
continue;
}
ImagePoint point = ImagePoint.getPoint(i, j, image);
if (point.getColor().equals(Color.WHITE)) {
pointsProcessed[point.x][point.y] = true;
continue;
}
Collection<ImagePoint> itemPoints = new ArrayList<ImagePoint>();
Queue<ImagePoint> pointsToProcess = new LinkedList<ImagePoint>();
pointsToProcess.add(point);
while (!pointsToProcess.isEmpty()) {
point = pointsToProcess.poll();
if (pointsProcessed[point.x][point.y]) {
continue;
}
pointsProcessed[point.x][point.y] = true;
if (point.getColor().equals(Color.WHITE)) {
continue;
}
itemPoints.add(point);
pointsToProcess.addAll(point.getNeighbors());
}
itemList.add(new Item(itemPoints));
}
}
return itemList;
}
private interface Point {
int getX();
int getY();
Color getColor();
}
private static final class ImagePoint implements Point {
private static final Map<BufferedImage, Map<Integer, Map<Integer, ImagePoint>>> POINT_CACHE = new HashMap<BufferedImage, Map<Integer, Map<Integer, ImagePoint>>>();
private final int x;
private final int y;
private final Color color;
private final BufferedImage image;
private Collection<ImagePoint> neighbors;
private ImagePoint(int x, int y, BufferedImage image) {
this.x = x;
this.y = y;
this.image = image;
this.color = new Color(image.getRGB(x, y));
}
static ImagePoint getPoint(int x, int y, BufferedImage image) {
Map<Integer, Map<Integer, ImagePoint>> imageCache = POINT_CACHE
.get(image);
if (imageCache == null) {
imageCache = new HashMap<Integer, Map<Integer, ImagePoint>>();
POINT_CACHE.put(image, imageCache);
}
Map<Integer, ImagePoint> xCache = imageCache.get(x);
if (xCache == null) {
xCache = new HashMap<Integer, Packer.ImagePoint>();
imageCache.put(x, xCache);
}
ImagePoint point = xCache.get(y);
if (point == null) {
point = new ImagePoint(x, y, image);
xCache.put(y, point);
}
return point;
}
Collection<ImagePoint> getNeighbors() {
if (neighbors == null) {
neighbors = new ArrayList<ImagePoint>();
for (int i = -1; i <= 1; i++) {
if (x + i < 0 || x + i >= image.getWidth()) {
continue;
}
for (int j = -1; j <= 1; j++) {
if ((i == j && i == 0) || y + j < 0
|| y + j >= image.getHeight()) {
continue;
}
neighbors.add(getPoint(x + i, y + j, image));
}
}
}
return neighbors;
}
@Override
public int getX() {
return y;
}
@Override
public int getY() {
return x;
}
@Override
public Color getColor() {
return color;
}
}
private static final class Item {
private final Collection<ItemPoint> points;
private final int width;
private final int height;
private final int perimiter;
private final int area;
Item(Collection<ImagePoint> points) {
int maxX = Integer.MIN_VALUE;
int minX = Integer.MAX_VALUE;
int maxY = Integer.MIN_VALUE;
int minY = Integer.MAX_VALUE;
for (ImagePoint point : points) {
maxX = Math.max(maxX, point.x);
minX = Math.min(minX, point.x);
maxY = Math.max(maxY, point.y);
minY = Math.min(minY, point.y);
}
this.width = maxX - minX;
this.height = maxY - minY;
this.perimiter = this.width * 2 + this.height * 2;
this.area = this.width * this.height;
this.points = new ArrayList<ItemPoint>(points.size());
for (ImagePoint point : points) {
this.points.add(new ItemPoint(point.x - minX, point.y - minY,
point.getColor()));
}
}
private static final class ItemPoint implements Point {
private final int x;
private final int y;
private final Color color;
public ItemPoint(int x, int y, Color color) {
this.x = x;
this.y = y;
this.color = color;
}
@Override
public int getX() {
return x;
}
@Override
public int getY() {
return y;
}
@Override
public Color getColor() {
return color;
}
}
}
private static final class PackedItem {
private final Collection<PackedPoint> points;
private Rotation rotation;
private int x;
private int y;
private AffineTransform transform;
private int modCount;
PackedItem(Item item, Rotation rotation, int x, int y) {
this.set(x, y, rotation);
this.points = new ArrayList<PackedPoint>();
for (Point point : item.points) {
this.points.add(new PackedPoint(point));
}
}
void set(int newX, int newY, Rotation newRotation) {
modCount++;
x = newX;
y = newY;
rotation = newRotation;
transform = new AffineTransform();
transform.translate(x, y);
transform.rotate(this.rotation.getDegrees());
}
void draw(Graphics g) {
Color oldColor = g.getColor();
for (Point point : points) {
g.setColor(point.getColor());
g.drawLine(point.getX(), point.getY(), point.getX(),
point.getY());
}
g.setColor(oldColor);
}
private enum Rotation {
ZERO(0), NINETY(Math.PI / 2), ONE_EIGHTY(Math.PI), TWO_SEVENTY(
3 * Math.PI / 2);
private final double degrees;
Rotation(double degrees) {
this.degrees = degrees;
}
double getDegrees() {
return degrees;
}
}
private final class PackedPoint implements Point {
private final Point point;
private final Point2D point2D;
private int x;
private int y;
private int modCount;
public PackedPoint(Point point) {
this.point = point;
this.point2D = new Point2D.Float(point.getX(), point.getY());
}
@Override
public int getX() {
update();
return x;
}
@Override
public int getY() {
update();
return y;
}
private void update() {
if (this.modCount != PackedItem.this.modCount) {
this.modCount = PackedItem.this.modCount;
Point2D destPoint = new Point2D.Float();
transform.transform(point2D, destPoint);
x = (int) destPoint.getX();
y = (int) destPoint.getY();
}
}
@Override
public Color getColor() {
return point.getColor();
}
}
}
private static final class Packing {
private final Set<PackedItem> packedItems = new HashSet<PackedItem>();
private final int maxWidth;
private boolean[][] pointsFilled;
private int height;
Packing(int maxWidth) {
this.maxWidth = maxWidth;
this.pointsFilled = new boolean[maxWidth][0];
}
void addItem(PackedItem item) {
packedItems.add(item);
for (Point point : item.points) {
height = Math.max(height, point.getY() + 1);
if (pointsFilled[point.getX()].length < point.getY() + 1) {
pointsFilled[point.getX()] = Arrays.copyOf(
pointsFilled[point.getX()], point.getY() + 1);
}
pointsFilled[point.getX()][point.getY()] = true;
}
}
BufferedImage getDrawing() {
BufferedImage image = new BufferedImage(maxWidth, height,
BufferedImage.TYPE_INT_ARGB);
Graphics g = image.getGraphics();
g.setColor(Color.WHITE);
g.drawRect(0, 0, maxWidth, height);
for (PackedItem item : packedItems) {
item.draw(g);
}
return image;
}
boolean isValidWith(PackedItem item) {
for (Point point : item.points) {
int x = point.getX();
int y = point.getY();
if (y < 0 || x < 0 || x >= maxWidth) {
return false;
}
boolean[] column = pointsFilled[x];
if (y < column.length && column[y]) {
return false;
}
}
return true;
}
}
}
Rozwiązanie, które tworzy (zajmuje około 4 minut 30 sekund na moim komputerze) to:
Patrząc na to zdjęcie, wydaje się, że wynik można poprawić, iterując wszystkie kształty po spakowaniu i próbując je nieco podnieść. Może spróbuję to zrobić później.
