added configuration file to define colors by polygonID

colorMappings.csv

+# polygonName, red (0 - 255), green (0 - 255), blue (0 - 255)

src/main/java/de/hft/stuttgart/citygml/viewer/CityGMLViewer.java

@@ -34,6 +34,7 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.imageio.ImageIO;
+import javax.swing.JOptionPane;
 import javax.xml.namespace.QName;
 import javax.xml.parsers.ParserConfigurationException;
 
@@ -117,6 +118,12 @@ public class CityGMLViewer {
 		}
 		try {
 			setupWindow(f);
+		} catch (Exception e) {
+			String message = e.getMessage();
+			if (e.getCause() != null) {
+				message += "\n" + e.getCause().getMessage();
+			}
+			JOptionPane.showMessageDialog(null, message, "Error", JOptionPane.ERROR_MESSAGE);
 		} finally {
 			for (PolygonViewInformation view : viewing) {
 				view.destroy();
@@ -372,9 +379,9 @@ public class CityGMLViewer {
 			try (ObservedInputStream ois = new ObservedInputStream(file);
 					CityGMLReader reader = in.createCityGMLReader(file.getAbsolutePath(), ois)) {
 				ois.addListener(p -> bar.drawProgress((int) (p * 82)));
-				
-		        int threads = Runtime.getRuntime().availableProcessors();
-		        ExecutorService service = Executors.newFixedThreadPool(threads);
+
+				int threads = Runtime.getRuntime().availableProcessors();
+				ExecutorService service = Executors.newFixedThreadPool(threads);
 				List<Future<FeatureMapper>> mappers = new ArrayList<>();
 				while (reader.hasNext()) {
 					CityGMLChunk nextChunk = reader.nextChunk();
@@ -414,8 +421,8 @@ public class CityGMLViewer {
 				Vector3d center = bbox.getCenter();
 				fMappers.forEach(m -> m.movePolygonsBy(center));
 				bar.drawProgress(82);
-				long nrOfPolygons = (long) lod1Polygons.size() + lod2Polygons.size()
-						+ lod3Polygons.size() + lod4Polygons.size();
+				long nrOfPolygons = (long) lod1Polygons.size() + lod2Polygons.size() + lod3Polygons.size()
+						+ lod4Polygons.size();
 				long[] count = new long[1];
 				log.info(() -> "Found " + nrOfPolygons + " polygons");
 				PolygonListener l = () -> {

src/main/java/de/hft/stuttgart/citygml/viewer/datastructure/Polygon.java

@@ -35,7 +35,7 @@ public class Polygon {
 	public Color getColor() {
 		return color;
 	}
-
+	
 	public Ring getExteriorRing() {
 		return exteriorRing;
 	}

src/main/java/de/hft/stuttgart/citygml/viewer/parser/FeatureMapper.java

@@ -93,7 +93,14 @@ public class FeatureMapper extends ObjectWalker {
 		if (currentPolygons == null) {
 			return;
 		}
-		Polygon viewerPoly = new Polygon(currentColor);
+		Color setColor = currentColor;
+		if (gmlPoly.getId() != null) {
+			Color mappedColor = PolygonColorMapper.getColorForPolygon(gmlPoly.getId());
+			if (mappedColor != null) {
+				setColor = mappedColor;
+			}
+		}
+		Polygon viewerPoly = new Polygon(setColor);
 		// parse rings
 		Ring extRing = new Ring();
 		viewerPoly.setExteriorRing(extRing);

src/main/java/de/hft/stuttgart/citygml/viewer/parser/PolygonColorMapper.java

+package de.hft.stuttgart.citygml.viewer.parser;
+
+import java.awt.Color;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Function;
+
+import javax.swing.JOptionPane;
+
+public class PolygonColorMapper {
+	
+	private static final String IGNORING_ALL_POLYGON_COLOR_MAPPINGS = "\nIgnoring all polygon color mappings";
+	private static Function<String, Color> producer;
+	private static Map<String, Color> colorMap;
+	
+	static {
+		loadColorMap();
+	}
+
+
+	private static void loadColorMap() {
+		Path colorMappingPath = Path.of("colorMappings.csv");
+		if (!Files.exists(colorMappingPath)) {
+			producer = s -> null;
+			return;
+		}
+		try (BufferedReader reader = Files.newBufferedReader(colorMappingPath)) {
+			colorMap = new HashMap<>();
+			String line = null;
+			while ((line = reader.readLine()) != null) {
+				if (line.startsWith("#")) {
+					// skip comments
+					continue;
+				}
+				String[] mappingStrings = line.split(",");
+				String polygonId = mappingStrings[0];
+				int r = Integer.parseInt(mappingStrings[1]);
+				if (r < 0 || r > 255) {
+					JOptionPane.showMessageDialog(null, "Wrong red value " + r + " for polygon: " + polygonId + IGNORING_ALL_POLYGON_COLOR_MAPPINGS, "Warning", JOptionPane.WARNING_MESSAGE);
+					colorMap = null;
+					producer = s -> null;
+					return;
+				}
+				int g = Integer.parseInt(mappingStrings[2]);
+				if (g < 0 || g > 255) {
+					JOptionPane.showMessageDialog(null, "Wrong green value " + g + " for polygon: " + polygonId + IGNORING_ALL_POLYGON_COLOR_MAPPINGS, "Warning", JOptionPane.WARNING_MESSAGE);
+					colorMap = null;
+					producer = s -> null;
+					return;
+				}
+				int b = Integer.parseInt(mappingStrings[3]);
+				if (b < 0 || b > 255) {
+					JOptionPane.showMessageDialog(null, "Wrong green value " + b + " for polygon: " + polygonId + IGNORING_ALL_POLYGON_COLOR_MAPPINGS, "Warning", JOptionPane.WARNING_MESSAGE);
+					colorMap = null;
+					producer = s -> null;
+					return;
+				}
+				Color color = new Color(r, g, b);
+				colorMap.put(polygonId, color);
+			}
+			if (colorMap.isEmpty()) {
+				producer = s -> null;
+			} else {
+				producer = s -> colorMap.get(s);
+			}
+		} catch (IOException e) {
+			JOptionPane.showMessageDialog(null, "Could not read mapping csv file, ignoring: " + e.getMessage(), "Warning", JOptionPane.WARNING_MESSAGE);
+		}
+	}
+	
+	
+	public static Color getColorForPolygon(String polygonId) {
+		return producer.apply(polygonId);
+	}
+	
+	private PolygonColorMapper() {
+	}
+
+}