Completed clue6

src/clue6/Main.java

@@ -0,0 +1,96 @@
+package clue6;
+
+import javax.imageio.ImageIO;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+
+public class Main {
+
+	public static void main(String[] args) {
+		try {
+			FileInputStream stream = new FileInputStream("clue6_data.png");
+			BufferedImage image = ImageIO.read(stream);
+			stream.close();
+			int width  = image.getWidth();
+			int height = image.getHeight();
+			int[] raw  = image.getRGB(0, 0, width, height, null, 0, width);
+			int[] output = new int[width * height];
+
+			for (int i = 0; i < width * height; ++i)
+				output[i] = 0xFF000000;
+
+			for (int i = 0; i < width * height; ++i) {
+				if (raw[i] != 0xFFFFFFFF) {
+					int other = findMatch(i, raw);
+					raw[i]     = 0xFFFFFFFF;
+					raw[other] = 0xFFFFFFFF;
+					if (i == 7559)
+						System.out.println(other % width + ", " + other / width);
+					connect(
+						i % width, i / width,
+						other % width, other / width,
+						width, output
+					);
+				}
+			}
+
+			image.setRGB(0, 0, width, height, output, 0, width);
+			ImageIO.write(image, "png", new File("clue6_output.png"));
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	private static int findMatch(int index, int[] data) {
+		int i = index;
+		while (++i < data.length && data[index] != data[i]);
+		return i;
+	}
+
+	private static void connect(int x0, int y0, int x1, int y1, int width, int[] write) {
+		boolean flip = (y0 > y1) != (x0 > x1);
+		int temp = x0;
+		x0 = Math.min(temp, x1);
+		x1 = Math.max(temp, x1);
+		temp = y0;
+		y0 = Math.min(temp, y1);
+		y1 = Math.max(temp, y1);
+		if (x0 == x1) {
+			for (int i = y0; i <= y1; ++i)
+				emit(x0, i, width, write);
+		}
+		else if (y0 == y1) {
+			for (int i = x0; i <= x1; ++i)
+				emit(i, y0, width, write);
+		}
+		else {
+			float xDiff = x1 - x0 + 1;
+			float yDiff = y1 - y0 + 1;
+			for (int i = 0; i < xDiff - 1; ++i) {
+				float begin = i / xDiff;
+				float end = (i + 1) / xDiff;
+				float avg = (begin + end) / 2;
+				for (int j = (int) (begin * yDiff); j <= end * yDiff; ++j) {
+					if (flip) {
+						if (j < avg * yDiff)
+							emit(x0 + i, y1 - j, width, write);
+						else
+							emit(x0 + i + 1, y1 - j, width, write);
+					}
+					else {
+						if (j < avg * yDiff)
+							emit(x0 + i, y0 + j, width, write);
+						else
+							emit(x0 + i + 1, y0 + j, width, write);
+					}
+				}
+			}
+		}
+	}
+
+	private static void emit(int x, int y, int width, int[] write) {
+		write[x + y * width] = 0xFFFF2277;
+	}
+}