From 911aa35577d36e5eeeacbdcbf23e72fba0c5a345 Mon Sep 17 00:00:00 2001
From: Manuel Friedli <manuel@fritteli.ch>
Date: Sat, 3 Oct 2020 23:09:50 +0200
Subject: [PATCH] Add a second page with the solution to the PDF.
---
.../java/ch/fritteli/labyrinth/Labyrinth.java | 2 +
.../ch/fritteli/labyrinth/PDFRenderer.java | 102 ++++++++++++++----
2 files changed, 82 insertions(+), 22 deletions(-)
diff --git a/src/main/java/ch/fritteli/labyrinth/Labyrinth.java b/src/main/java/ch/fritteli/labyrinth/Labyrinth.java
index 5e5be59..b5c6244 100644
--- a/src/main/java/ch/fritteli/labyrinth/Labyrinth.java
+++ b/src/main/java/ch/fritteli/labyrinth/Labyrinth.java
@@ -13,7 +13,9 @@ public class Labyrinth {
private final int width;
@Getter
private final int height;
+ @Getter
private final Position start;
+ @Getter
private final Position end;
public Labyrinth(final int width, final int height) {
diff --git a/src/main/java/ch/fritteli/labyrinth/PDFRenderer.java b/src/main/java/ch/fritteli/labyrinth/PDFRenderer.java
index 5dad450..7b2d6ae 100644
--- a/src/main/java/ch/fritteli/labyrinth/PDFRenderer.java
+++ b/src/main/java/ch/fritteli/labyrinth/PDFRenderer.java
@@ -5,12 +5,16 @@ import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
+import org.jetbrains.annotations.Nullable;
import java.awt.*;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
public class PDFRenderer implements Renderer<byte[]> {
+ private static final float MARGIN = 10;
+ private static final float SCALE = 10;
+
private PDFRenderer() {
}
@@ -20,13 +24,15 @@ public class PDFRenderer implements Renderer<byte[]> {
return new PDFRenderer();
}
+ private static boolean isValid(@NonNull final Position position) {
+ return position.getX() >= 0 && position.getY() >= 0;
+ }
+
@Override
@NonNull
public byte[] render(@NonNull final Labyrinth labyrinth) {
- final float scale = 10;
- final float margin = 5;
- final float pageWidth = labyrinth.getWidth() * scale + 2 * margin;
- final float pageHeight = labyrinth.getHeight() * scale + 2 * margin;
+ final float pageWidth = labyrinth.getWidth() * SCALE + 2 * MARGIN;
+ final float pageHeight = labyrinth.getHeight() * SCALE + 2 * MARGIN;
final PDDocument pdDocument = new PDDocument();
final PDPage page = new PDPage(new PDRectangle(pageWidth, pageHeight));
@@ -37,8 +43,22 @@ public class PDFRenderer implements Renderer<byte[]> {
pdPageContentStream.setLineWidth(1.0f);
pdPageContentStream.setStrokingColor(Color.BLACK);
pdPageContentStream.setNonStrokingColor(Color.BLACK);
- this.drawHorizonzalLines(labyrinth, pdPageContentStream, margin, scale);
- this.drawVerticalLines(labyrinth, pdPageContentStream, margin, scale);
+ this.drawHorizonzalLines(labyrinth, pdPageContentStream);
+ this.drawVerticalLines(labyrinth, pdPageContentStream);
+ } catch (IOException e) {
+ e.printStackTrace();
+ }
+ final PDPage solution = new PDPage(new PDRectangle(pageWidth, pageHeight));
+ pdDocument.addPage(solution);
+ try (PDPageContentStream pdPageContentStream = new PDPageContentStream(pdDocument, solution)) {
+ pdPageContentStream.setLineCapStyle(BasicStroke.CAP_ROUND);
+ pdPageContentStream.setLineJoinStyle(BasicStroke.JOIN_MITER);
+ pdPageContentStream.setLineWidth(1.0f);
+ pdPageContentStream.setStrokingColor(Color.BLACK);
+ pdPageContentStream.setNonStrokingColor(Color.BLACK);
+ this.drawHorizonzalLines(labyrinth, pdPageContentStream);
+ this.drawVerticalLines(labyrinth, pdPageContentStream);
+ this.drawSolution(labyrinth, pdPageContentStream);
} catch (IOException e) {
e.printStackTrace();
}
@@ -52,28 +72,29 @@ public class PDFRenderer implements Renderer<byte[]> {
return output.toByteArray();
}
- private void drawHorizonzalLines(@NonNull final Labyrinth labyrinth, @NonNull final PDPageContentStream pdPageContentStream, final float margin, final float scale) throws IOException {
+ private void drawHorizonzalLines(@NonNull final Labyrinth labyrinth,
+ @NonNull final PDPageContentStream pdPageContentStream) throws IOException {
// PDF has the origin in the lower left corner. We want it in the upper left corner, hence some magic is required.
- final float labyrinthHeight = labyrinth.getHeight() * scale;
+ final float labyrinthHeight = labyrinth.getHeight() * SCALE;
for (int y = 0; y < labyrinth.getHeight(); y++) {
boolean isPainting = false;
for (int x = 0; x < labyrinth.getWidth(); x++) {
final Tile currentTile = labyrinth.getTileAt(x, y);
if (currentTile.hasWallAt(Direction.TOP)) {
if (!isPainting) {
- pdPageContentStream.moveTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.moveTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
isPainting = true;
}
} else {
if (isPainting) {
- pdPageContentStream.lineTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.lineTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
pdPageContentStream.stroke();
isPainting = false;
}
}
}
if (isPainting) {
- pdPageContentStream.lineTo(labyrinth.getWidth() * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.lineTo(labyrinth.getWidth() * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
pdPageContentStream.stroke();
}
}
@@ -83,45 +104,46 @@ public class PDFRenderer implements Renderer<byte[]> {
final Tile currentTile = labyrinth.getTileAt(x, y - 1);
if (currentTile.hasWallAt(Direction.BOTTOM)) {
if (!isPainting) {
- pdPageContentStream.moveTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.moveTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
isPainting = true;
}
} else {
if (isPainting) {
- pdPageContentStream.lineTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.lineTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
pdPageContentStream.stroke();
isPainting = false;
}
}
}
if (isPainting) {
- pdPageContentStream.lineTo(labyrinth.getWidth() * scale + margin, labyrinthHeight - labyrinth.getHeight() * scale + margin);
+ pdPageContentStream.lineTo(labyrinth.getWidth() * SCALE + MARGIN, labyrinthHeight - labyrinth.getHeight() * SCALE + MARGIN);
pdPageContentStream.stroke();
}
}
- private void drawVerticalLines(@NonNull final Labyrinth labyrinth, @NonNull final PDPageContentStream pdPageContentStream, final float margin, final float scale) throws IOException {
+ private void drawVerticalLines(@NonNull final Labyrinth labyrinth,
+ @NonNull final PDPageContentStream pdPageContentStream) throws IOException {
// PDF has the origin in the lower left corner. We want it in the upper left corner, hence some magic is required.
- final float labyrinthHeight = labyrinth.getHeight() * scale;
+ final float labyrinthHeight = labyrinth.getHeight() * SCALE;
for (int x = 0; x < labyrinth.getWidth(); x++) {
boolean isPainting = false;
for (int y = 0; y < labyrinth.getHeight(); y++) {
final Tile currentTile = labyrinth.getTileAt(x, y);
if (currentTile.hasWallAt(Direction.LEFT)) {
if (!isPainting) {
- pdPageContentStream.moveTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.moveTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
isPainting = true;
}
} else {
if (isPainting) {
- pdPageContentStream.lineTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.lineTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
pdPageContentStream.stroke();
isPainting = false;
}
}
}
if (isPainting) {
- pdPageContentStream.lineTo(x * scale + margin, labyrinthHeight - labyrinth.getHeight() * scale + margin);
+ pdPageContentStream.lineTo(x * SCALE + MARGIN, labyrinthHeight - labyrinth.getHeight() * SCALE + MARGIN);
pdPageContentStream.stroke();
}
}
@@ -131,20 +153,56 @@ public class PDFRenderer implements Renderer<byte[]> {
final Tile currentTile = labyrinth.getTileAt(x - 1, y);
if (currentTile.hasWallAt(Direction.RIGHT)) {
if (!isPainting) {
- pdPageContentStream.moveTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.moveTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
isPainting = true;
}
} else {
if (isPainting) {
- pdPageContentStream.lineTo(x * scale + margin, labyrinthHeight - y * scale + margin);
+ pdPageContentStream.lineTo(x * SCALE + MARGIN, labyrinthHeight - y * SCALE + MARGIN);
pdPageContentStream.stroke();
isPainting = false;
}
}
}
if (isPainting) {
- pdPageContentStream.lineTo(labyrinth.getWidth() * scale + margin, labyrinthHeight - labyrinth.getHeight() * scale + margin);
+ pdPageContentStream.lineTo(labyrinth.getWidth() * SCALE + MARGIN, labyrinthHeight - labyrinth.getHeight() * SCALE + MARGIN);
pdPageContentStream.stroke();
}
}
+
+ private void drawSolution(@NonNull final Labyrinth labyrinth,
+ @NonNull final PDPageContentStream pdPageContentStream) throws IOException {
+ // Draw the solution in red
+ pdPageContentStream.setStrokingColor(Color.RED);
+ // PDF has the origin in the lower left corner. We want it in the upper left corner, hence some magic is required.
+ final float labyrinthHeight = labyrinth.getHeight() * SCALE;
+ final Position end = labyrinth.getEnd();
+ Position currentPosition = labyrinth.getStart();
+ Position previousPosition = null;
+ pdPageContentStream.moveTo(MARGIN + currentPosition.getX() * SCALE + SCALE / 2, MARGIN + labyrinthHeight - (currentPosition.getY() * SCALE + SCALE / 2));
+ do {
+ Position newCurrent = this.findNextSolutionPosition(labyrinth, previousPosition, currentPosition);
+ previousPosition = currentPosition;
+ currentPosition = newCurrent;
+ pdPageContentStream.lineTo(MARGIN + currentPosition.getX() * SCALE + SCALE / 2, MARGIN + labyrinthHeight - (currentPosition.getY() * SCALE + SCALE / 2));
+ } while (!currentPosition.equals(end));
+ pdPageContentStream.stroke();
+ }
+
+ private Position findNextSolutionPosition(@NonNull final Labyrinth labyrinth, @Nullable final Position previousPosition, @NonNull final Position currentPosition) {
+ final Tile currentTile = labyrinth.getTileAt(currentPosition);
+ for (final Direction direction : Direction.values()) {
+ if (!currentTile.hasWallAt(direction)) {
+ final Position position = direction.translate(currentPosition);
+ if (position.equals(previousPosition) || !isValid(position)) {
+ continue;
+ }
+ if (labyrinth.getTileAt(position).isSolution()) {
+ return position;
+ }
+ }
+ }
+ // We *SHOULD* never get here. ... famous last words ...
+ return null;
+ }
}