Merge branch 'dev' into...

Merge branch 'dev' into 122-ge_s_not_closed-ge_s_multiple_connected_components-due-to-unresolved-triangulatedsurface-x-link

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Changed
+- Replaced the JavaFX-based 3D view with an OpenGL renderer (openglfx/JOGL) for smooth display of
+  large city models. Picking is now GPU-based; the 3D view requires OpenGL 3.3 (Windows/Linux).
+
 ## [3.18.3] (2026-04-16)
 
 ### Fixes

CityDoctorParent/Extensions/CityDoctorGUI/pom.xml

@@ -59,6 +59,24 @@
 			<groupId>org.openjfx</groupId>
 			<artifactId>javafx-swing</artifactId>
 		</dependency>
+		<!-- https://mvnrepository.com/artifact/com.huskerdev/openglfx-jogl -->
+		<dependency>
+			<groupId>com.huskerdev</groupId>
+			<artifactId>openglfx-jogl</artifactId>
+			<version>4.1.19</version>
+		</dependency>
+		<!-- JOGL runtime + platform natives. openglfx-jogl does not declare JOGL itself;
+		     the GUI now programs directly against com.jogamp.opengl, so depend on it explicitly.
+		     Versions are managed in the parent pom. The -main artifacts bundle the natives. -->
+		<dependency>
+			<groupId>org.jogamp.jogl</groupId>
+			<artifactId>jogl-all-main</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.jogamp.gluegen</groupId>
+			<artifactId>gluegen-rt-main</artifactId>
+		</dependency>
+
 	</dependencies>
 	<profiles>
 		<profile>

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CityDoctorController.java

@@ -130,7 +130,7 @@ public class CityDoctorController {
                 mainWindow.getOpenBtn().setDisable(true);
 
                 mainWindow.getWriteReportButton().setDisable(true);
-                mainWindow.getMeshGroup().getChildren().clear();
+                mainWindow.clearMeshView();
 
                 clearTrees();
                 mainWindow.resetSearchBar();
@@ -1660,7 +1660,7 @@ public class CityDoctorController {
     }
 
     public void errorFilterIndexChanged(Number newV) {
-        mainWindow.getMeshGroup().getChildren().clear();
+        mainWindow.clearMeshView();
         mainWindow.unselectEverything();
         mainWindow.resetSearchBar();
         renderer.clearCurrentRender();

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/HighlightController.java

 package de.hft.stuttgart.citydoctor2.gui;
 
 import java.util.List;
+import java.util.function.Supplier;
 
 import de.hft.stuttgart.citydoctor2.datastructure.Edge;
 import de.hft.stuttgart.citydoctor2.datastructure.LinearRing;
 import de.hft.stuttgart.citydoctor2.datastructure.Polygon;
 import de.hft.stuttgart.citydoctor2.datastructure.Vertex;
 import de.hft.stuttgart.citydoctor2.datastructure.LinearRing.LinearRingType;
+import de.hft.stuttgart.citydoctor2.gui.gl.FloatList;
+import de.hft.stuttgart.citydoctor2.gui.gl.GLViewport;
 import de.hft.stuttgart.citydoctor2.math.Triangle3d;
 import de.hft.stuttgart.citydoctor2.math.Vector3d;
-import javafx.application.Platform;
-import javafx.geometry.Point3D;
-import javafx.scene.Group;
-import javafx.scene.Node;
 import javafx.scene.paint.Color;
-import javafx.scene.paint.PhongMaterial;
-import javafx.scene.shape.Cylinder;
-import javafx.scene.shape.Sphere;
-import javafx.scene.transform.Rotate;
-import javafx.scene.transform.Translate;
 
+/**
+ * Accumulates highlight marker geometry (points and lines) and pushes it to the {@link GLViewport}
+ * overlay. Coordinates are recentred by the current scene center supplied by the {@link Renderer}.
+ */
 public class HighlightController {
-	
-	
-	private double scale;
-	private Group points;
-	private Group edges;
-
-	private Group highlights;
-	
-	public HighlightController(Group world) {
-		highlights = new Group();
-		points = new Group();
-		edges = new Group();
-		highlights.getChildren().add(edges);
-		highlights.getChildren().add(points);
-		Platform.runLater(() -> world.getChildren().add(highlights));
-	}
-	
-	public void clearHighlights() {
-		points.getChildren().clear();
-		edges.getChildren().clear();
-	}
-	
-	public void changeScaling(double translateZ) {
-		scale = Math.abs(translateZ);
-		scale = Math.min(150, scale);
-		scale = Math.max(10, scale);
-		scale = scale * 0.01;
-		for (Node n : points.getChildren()) {
-			n.setScaleX(scale);
-			n.setScaleY(scale);
-			n.setScaleZ(scale);
-		}
-		double edgeSize = scale / 10;
-		for (Node n : edges.getChildren()) {
-			if (n instanceof Cylinder cy) {
-				cy.setRadius(edgeSize);
-			}
-		}
-	}
-	
-	public void highlight(Polygon p, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		addHighlight(p, currentTriGeom, Color.RED, Color.BLUE);
-	}
-
-	private void addHighlight(Polygon p, TriangulatedGeometry currentTriGeom, Color extColor, Color intColor) {
-		if (currentTriGeom == null || p == null) {
-			return;
-		}
-		addHighlight(p.getExteriorRing(), currentTriGeom, extColor);
-		for (LinearRing intRing : p.getInnerRings()) {
-			addHighlight(intRing, currentTriGeom, intColor);
-		}
-	}
-	
-	public void highlight(LinearRing ring, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		if (ring.getType() == LinearRingType.EXTERIOR) {
-			addHighlight(ring, currentTriGeom, Color.RED);
-		} else {
-			addHighlight(ring, currentTriGeom, Color.BLUE);
-		}
-	}
-	
-	public void highlight(List<LinearRing> rings, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		for (LinearRing lr : rings) {
-			if (lr.getType() == LinearRingType.EXTERIOR) {
-				addHighlight(lr, currentTriGeom, Color.RED);
-			} else {
-				addHighlight(lr, currentTriGeom, Color.BLUE);
-			}
-		}
-	}
-
-	private void addHighlight(LinearRing ring, TriangulatedGeometry currentTriGeom, Color pointColor) {
-		if (currentTriGeom == null || ring == null) {
-			return;
-		}
-		Vector3d movedBy = currentTriGeom.getMovedBy();
-		for (Vertex v : ring.getVertices()) {
-			highlightPoint(movedBy, v, pointColor);
-		}
-		for (int i = 0; i < ring.getVertices().size() - 1; i++) {
-			Vertex v1 = ring.getVertices().get(i);
-			Vertex v2 = ring.getVertices().get(i + 1);
-			highlightEdge(v1, v2, movedBy);
-		}
-	}
-	
-	public void highlight(Edge e, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		addHighlight(e, currentTriGeom);
-	}
-
-	private void addHighlight(Edge e, TriangulatedGeometry currentTriGeom) {
-		if (currentTriGeom == null || e == null) {
-			return;
-		}
-		Vector3d movedBy = currentTriGeom.getMovedBy();
-		highlightEdge(e.getFrom(), e.getTo(), movedBy);
-		highlightPoint(movedBy, e.getFrom(), Color.RED);
-		highlightPoint(movedBy, e.getTo(), Color.RED);
-	}
-	
-	public void highlight(Vertex v, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		addHighlight(v, currentTriGeom, Color.RED);
-	}
-
-	public void addHighlight(Vertex v, TriangulatedGeometry currentTriGeom, Color c) {
-		if (currentTriGeom == null || v == null) {
-			return;
-		}
-		Vector3d movedBy = currentTriGeom.getMovedBy();
-		highlightPoint(movedBy, v, c);
-	}
-	
-	private void highlightPoint(Vector3d movedBy, Vertex v, Color color) {
-		Sphere sp = new Sphere(0.5);
-		sp.setMaterial(new PhongMaterial(color));
-		sp.setTranslateX(v.getX() - movedBy.getX());
-		sp.setTranslateY(v.getY() - movedBy.getY());
-		sp.setTranslateZ(v.getZ() - movedBy.getZ());
-		sp.setScaleX(scale);
-		sp.setScaleY(scale);
-		sp.setScaleZ(scale);
-		
-		sp.setUserData(new VertexClickDispatcher(v));
-		
-		points.getChildren().add(sp);
-	}
-	
-	private void highlightEdge(Vector3d v1, Vector3d v2, Vector3d movedBy) {
-		Point3D origin = new Point3D(v1.getX() - movedBy.getX(), v1.getY() - movedBy.getY(),
-				v1.getZ() - movedBy.getZ());
-		Point3D target = new Point3D(v2.getX() - movedBy.getX(), v2.getY() - movedBy.getY(),
-				v2.getZ() - movedBy.getZ());
-
-		Point3D yAxis = new Point3D(0, 1, 0);
-		Point3D diff = target.subtract(origin);
-		double height = diff.magnitude();
-
-		Point3D mid = target.midpoint(origin);
-		Translate moveToMidpoint = new Translate(mid.getX(), mid.getY(), mid.getZ());
-
-		Point3D axisOfRotation = diff.crossProduct(yAxis);
-		double angle = Math.acos(diff.normalize().dotProduct(yAxis));
-		Rotate rotateAroundCenter = new Rotate(-Math.toDegrees(angle), axisOfRotation);
-
-		Cylinder cy = new Cylinder(scale / 10, height);
-		cy.setMaterial(new PhongMaterial(Color.ORANGE));
-		cy.getTransforms().addAll(moveToMidpoint, rotateAroundCenter);
-		edges.getChildren().add(cy);
-	}
-
-	public void highlightEdges(List<Edge> errorEdges, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		for (Edge e : errorEdges) {
-			addHighlight(e, currentTriGeom);
-		}
-	}
-
-	public void highlightPolygons(List<List<Polygon>> components, TriangulatedGeometry currentTriGeom) {
-		clearHighlights();
-		for (int i = 0; i < components.size(); i++) {
-			Color extColor;
-			Color intColor = switch (i % 3) {
+
+    private final GLViewport viewport;
+    private Supplier<double[]> centerSupplier;
+
+    private final FloatList points = new FloatList();
+    private final FloatList pointColors = new FloatList();
+    private final FloatList lines = new FloatList();
+    private final FloatList lineColors = new FloatList();
+
+    public HighlightController(GLViewport viewport) {
+        this.viewport = viewport;
+    }
+
+    public void setCenterSupplier(Supplier<double[]> centerSupplier) {
+        this.centerSupplier = centerSupplier;
+    }
+
+    private double[] center() {
+        if (centerSupplier == null) {
+            return new double[3];
+        }
+        double[] c = centerSupplier.get();
+        return c == null ? new double[3] : c;
+    }
+
+    private void resetBuffers() {
+        points.clear();
+        pointColors.clear();
+        lines.clear();
+        lineColors.clear();
+    }
+
+    public void clearHighlights() {
+        resetBuffers();
+        push();
+    }
+
+    private void push() {
+        viewport.setHighlights(points.toArray(), pointColors.toArray(), lines.toArray(), lineColors.toArray());
+    }
+
+    public void changeScaling(double translateZ) {
+        // GL points/lines are sized in screen pixels, so highlight markers keep a constant on-screen
+        // size regardless of zoom distance; nothing to recompute here.
+    }
+
+    // ---- point/line accumulation ----
+
+    private void addPoint(Vertex v, Color color) {
+        double[] c = center();
+        points.add((float) (v.getX() - c[0]), (float) (v.getY() - c[1]), (float) (v.getZ() - c[2]));
+        pointColors.add((float) color.getRed(), (float) color.getGreen(), (float) color.getBlue());
+    }
+
+    private void addLine(Vector3d v1, Vector3d v2, Color color) {
+        double[] c = center();
+        lines.add((float) (v1.getX() - c[0]), (float) (v1.getY() - c[1]), (float) (v1.getZ() - c[2]));
+        lines.add((float) (v2.getX() - c[0]), (float) (v2.getY() - c[1]), (float) (v2.getZ() - c[2]));
+        float r = (float) color.getRed();
+        float g = (float) color.getGreen();
+        float b = (float) color.getBlue();
+        lineColors.add(r, g, b);
+        lineColors.add(r, g, b);
+    }
+
+    // ---- public highlight API ----
+
+    public void highlight(Polygon p) {
+        resetBuffers();
+        addHighlight(p, Color.RED, Color.BLUE);
+        push();
+    }
+
+    private void addHighlight(Polygon p, Color extColor, Color intColor) {
+        if (p == null) {
+            return;
+        }
+        addHighlight(p.getExteriorRing(), extColor);
+        for (LinearRing intRing : p.getInnerRings()) {
+            addHighlight(intRing, intColor);
+        }
+    }
+
+    public void highlight(LinearRing ring) {
+        resetBuffers();
+        if (ring.getType() == LinearRingType.EXTERIOR) {
+            addHighlight(ring, Color.RED);
+        } else {
+            addHighlight(ring, Color.BLUE);
+        }
+        push();
+    }
+
+    public void highlight(List<LinearRing> rings) {
+        resetBuffers();
+        for (LinearRing lr : rings) {
+            if (lr.getType() == LinearRingType.EXTERIOR) {
+                addHighlight(lr, Color.RED);
+            } else {
+                addHighlight(lr, Color.BLUE);
+            }
+        }
+        push();
+    }
+
+    private void addHighlight(LinearRing ring, Color pointColor) {
+        if (ring == null) {
+            return;
+        }
+        for (Vertex v : ring.getVertices()) {
+            addPoint(v, pointColor);
+        }
+        for (int i = 0; i < ring.getVertices().size() - 1; i++) {
+            Vertex v1 = ring.getVertices().get(i);
+            Vertex v2 = ring.getVertices().get(i + 1);
+            addLine(v1, v2, Color.ORANGE);
+        }
+    }
+
+    public void highlight(Edge e) {
+        resetBuffers();
+        addHighlight(e);
+        push();
+    }
+
+    private void addHighlight(Edge e) {
+        if (e == null) {
+            return;
+        }
+        addLine(e.getFrom(), e.getTo(), Color.ORANGE);
+        addPoint(e.getFrom(), Color.RED);
+        addPoint(e.getTo(), Color.RED);
+    }
+
+    public void highlight(Vertex v) {
+        resetBuffers();
+        addPoint(v, Color.RED);
+        push();
+    }
+
+    public void addHighlight(Vertex v, Color c) {
+        if (v == null) {
+            return;
+        }
+        addPoint(v, c);
+        push();
+    }
+
+    public void highlightEdges(List<Edge> errorEdges) {
+        resetBuffers();
+        for (Edge e : errorEdges) {
+            addHighlight(e);
+        }
+        push();
+    }
+
+    public void highlightPolygons(List<List<Polygon>> components) {
+        resetBuffers();
+        for (int i = 0; i < components.size(); i++) {
+            Color extColor;
+            Color intColor = switch (i % 3) {
                 case 1 -> {
                     extColor = Color.GREEN;
                     yield Color.YELLOW;
@@ -202,21 +193,24 @@ public class HighlightController {
                     yield Color.BLUE;
                 }
             };
-			// select some color pairs for exterior and inner rings
+            // select some color pairs for exterior and inner rings
             List<Polygon> component = components.get(i);
-			for (Polygon p : component) {
-				addHighlight(p, currentTriGeom, extColor, intColor);
-			}
-		}
-	}
-
-	public void addHighlight(Polygon p, TriangulatedGeometry currentTriGeom) {
-		addHighlight(p, currentTriGeom, Color.RED, Color.BLUE);
-	}
-
-	public void highlight(Triangle3d t, TriangulatedGeometry currentTriGeom) {
-		highlightEdge(t.getP1(), t.getP2(), currentTriGeom.getMovedBy());
-		highlightEdge(t.getP2(), t.getP3(), currentTriGeom.getMovedBy());
-		highlightEdge(t.getP3(), t.getP1(), currentTriGeom.getMovedBy());
-	}
+            for (Polygon p : component) {
+                addHighlight(p, extColor, intColor);
+            }
+        }
+        push();
+    }
+
+    public void addHighlight(Polygon p) {
+        addHighlight(p, Color.RED, Color.BLUE);
+        push();
+    }
+
+    public void highlight(Triangle3d t) {
+        addLine(t.getP1(), t.getP2(), Color.ORANGE);
+        addLine(t.getP2(), t.getP3(), Color.ORANGE);
+        addLine(t.getP3(), t.getP1(), Color.ORANGE);
+        push();
+    }
 }

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ListErrorVisitor.java

@@ -55,32 +55,27 @@ import javafx.scene.paint.Color;
 public class ListErrorVisitor implements ErrorVisitor {
 	
 	private HighlightController controller;
-	private TriangulatedGeometry geom;
-	
+
 	public ListErrorVisitor(HighlightController controller) {
 		this.controller = controller;
 	}
-	
-	public void setGeometry(TriangulatedGeometry geom) {
-		this.geom = geom;
-	}
 
 	@Override
 	public void visit(PolygonHoleOutsideError err) {
 		List<LinearRing> highlightedRings = new ArrayList<>();
 		highlightedRings.add(err.getPolygon().getExteriorRing());
 		highlightedRings.addAll(err.getHolesOutside());
-		controller.highlight(highlightedRings, geom);
+		controller.highlight(highlightedRings);
 	}
 
 	@Override
 	public void visit(NonManifoldEdgeError err) {
-		controller.highlightEdges(err.getEdges(), geom);
+		controller.highlightEdges(err.getEdges());
 	}
 
 	@Override
 	public void visit(MultipleConnectedComponentsError err) {
-		controller.highlightPolygons(err.getComponents(), geom);
+		controller.highlightPolygons(err.getComponents());
 	}
 
 	@Override
@@ -88,18 +83,18 @@ public class ListErrorVisitor implements ErrorVisitor {
 		List<LinearRing> highlightedRings = new ArrayList<>();
 		highlightedRings.add(err.getPolygon().getExteriorRing());
 		highlightedRings.add(err.getInnerRing());
-		controller.highlight(highlightedRings, geom);
+		controller.highlight(highlightedRings);
 	}
 
 	@Override
 	public void visit(NonManifoldVertexError err) {
-		controller.highlightPolygons(err.getComponents(), geom);
-		controller.addHighlight(err.getVertex(), geom, Color.BLUEVIOLET);
+		controller.highlightPolygons(err.getComponents());
+		controller.addHighlight(err.getVertex(), Color.BLUEVIOLET);
 	}
 
 	@Override
 	public void visit(PolygonWrongOrientationError err) {
-		controller.highlightEdges(err.getEdges(), geom);
+		controller.highlightEdges(err.getEdges());
 	}
 
 	@Override
@@ -107,12 +102,12 @@ public class ListErrorVisitor implements ErrorVisitor {
 		List<LinearRing> highlightedRings = new ArrayList<>();
 		highlightedRings.add(err.getPolygon().getExteriorRing());
 		highlightedRings.add(err.getInnerRing());
-		controller.highlight(highlightedRings, geom);
+		controller.highlight(highlightedRings);
 	}
 
 	@Override
 	public void visit(SolidNotClosedError err) {
-		controller.highlightEdges(err.getErrorEdges(), geom);
+		controller.highlightEdges(err.getErrorEdges());
 	}
 
 	@Override
@@ -127,14 +122,14 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(RingNotClosedError err) {
-		controller.highlight(err.getRing(), geom);
+		controller.highlight(err.getRing());
 	}
 
 	@Override
 	public void visit(ConsecutivePointSameError err) {
-		controller.highlight(err.getRing(), geom);
-		controller.addHighlight(err.getVertex1(), geom, Color.BLACK);
-		controller.addHighlight(err.getVertex2(), geom, Color.BLACK);
+		controller.highlight(err.getRing());
+		controller.addHighlight(err.getVertex1(), Color.BLACK);
+		controller.addHighlight(err.getVertex2(), Color.BLACK);
 	}
 
 	@Override
@@ -144,7 +139,7 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(PolygonInteriorDisconnectedError err) {
-		controller.highlight(err.getConnectedRings(), geom);
+		controller.highlight(err.getConnectedRings());
 	}
 
 	@Override
@@ -154,18 +149,18 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(RingTooFewPointsError err) {
-		controller.highlight(err.getRing(), geom);
+		controller.highlight(err.getRing());
 	}
 
 	@Override
 	public void visit(NonPlanarPolygonNormalsDeviation err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override
 	public void visit(NonPlanarPolygonDistancePlaneError err) {
-		controller.highlight(err.getPolygon(), geom);
-		controller.addHighlight(err.getVertex(), geom, Color.BLACK);
+		controller.highlight(err.getPolygon());
+		controller.addHighlight(err.getVertex(), Color.BLACK);
 	}
 
 	@Override
@@ -173,15 +168,15 @@ public class ListErrorVisitor implements ErrorVisitor {
 		List<LinearRing> rings = new ArrayList<>();
 		rings.add(err.getIntersectingRings().getValue0());
 		rings.add(err.getIntersectingRings().getValue1());
-		controller.highlight(rings, geom);
+		controller.highlight(rings);
 	}
 
 	@Override
 	public void visit(SolidSelfIntError err) {
 		controller.clearHighlights();
 		for (PolygonIntersection intersection : err.getIntersections()) {
-			controller.addHighlight(intersection.getP1(), geom);
-			controller.addHighlight(intersection.getP2(), geom);
+			controller.addHighlight(intersection.getP1());
+			controller.addHighlight(intersection.getP2());
 		}
 	}
 
@@ -192,9 +187,9 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(RingDuplicatePointError err) {
-		controller.highlight(err.getRing(), geom);
-		controller.addHighlight(err.getVertex1(), geom, Color.BLACK);
-		controller.addHighlight(err.getVertex2(), geom, Color.BLACK);
+		controller.highlight(err.getRing());
+		controller.addHighlight(err.getVertex1(), Color.BLACK);
+		controller.addHighlight(err.getVertex2(), Color.BLACK);
 	}
 
 	@Override
@@ -202,14 +197,14 @@ public class ListErrorVisitor implements ErrorVisitor {
 		List<Edge> list = new ArrayList<>();
 		list.add(err.getEdge1());
 		list.add(err.getEdge2());
-		controller.highlightEdges(list, geom);
-		controller.addHighlight(new Vertex(err.getIntersection()), geom, Color.BLACK);
+		controller.highlightEdges(list);
+		controller.addHighlight(new Vertex(err.getIntersection()), Color.BLACK);
 	}
 
 	@Override
 	public void visit(PointTouchesEdgeError err) {
-		controller.highlight(err.getEdge(), geom);
-		controller.addHighlight(err.getVertex(), geom, Color.BLACK);
+		controller.highlight(err.getEdge());
+		controller.addHighlight(err.getVertex(), Color.BLACK);
 	}
 
 	@Override
@@ -219,22 +214,22 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(NotCeilingError err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override
 	public void visit(NotFloorError err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override
 	public void visit(NotWallError err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override
 	public void visit(NotGroundError err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override
@@ -249,7 +244,7 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(DegeneratedRingError err) {
-		controller.highlight(err.getRing(), geom);
+		controller.highlight(err.getRing());
 	}
 
 	@Override
@@ -269,7 +264,7 @@ public class ListErrorVisitor implements ErrorVisitor {
 
 	@Override
 	public void visit(PolygonWithoutSurfaceError err) {
-		controller.highlight(err.getPolygon(), geom);
+		controller.highlight(err.getPolygon());
 	}
 
 	@Override

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/MainWindow.java

@@ -31,9 +31,11 @@ import javafx.scene.layout.BorderPane;
 import javafx.scene.layout.HBox;
 import javafx.scene.layout.Pane;
 import javafx.scene.layout.Priority;
+import javafx.scene.layout.Region;
 import javafx.scene.paint.Color;
-import javafx.scene.transform.Rotate;
 import javafx.stage.Stage;
+import de.hft.stuttgart.citydoctor2.gui.gl.GLViewport;
+import de.hft.stuttgart.citydoctor2.datastructure.Polygon;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -49,10 +51,6 @@ public class MainWindow extends Application {
 
     private static final Logger logger = LogManager.getLogger(MainWindow.class);
 
-    private static final double CAMERA_TRANSLATE_Z = -100.0;
-    private static final double CAMERA_INITIAL_X_ANGLE = 20.0;
-    private static final double CAMERA_INITIAL_Y_ANGLE = 120.0;
-
     @FXML
     private TreeView<Renderable> buildingsView;
 
@@ -214,19 +212,8 @@ public class MainWindow extends Application {
     private Image north;
     private Image northFlip;
 
-    private Group meshGroup;
-
-    private Group world;
-    private PerspectiveCamera camera;
-    private Rotate cameraXRotation = new Rotate();
-    private Rotate cameraZRotation = new Rotate();
-
-    private double dragX;
-    private double dragY;
+    private GLViewport glViewport;
 
-    private double cameraXRot = CAMERA_INITIAL_X_ANGLE;
-    private double cameraYRot = CAMERA_INITIAL_Y_ANGLE;
-    private double translateZ = CAMERA_TRANSLATE_Z;
     private double[] clickStart = new double[2];
 
     @FXML
@@ -245,7 +232,6 @@ public class MainWindow extends Application {
     private FeatureType selectedTab = FeatureType.BUILDING;
 
     private MainToolBar mainToolBar;
-    private SubScene geomScene;
     private ImageView northArrow;
 
     private static boolean loadFileAtStartup = false;
@@ -259,6 +245,11 @@ public class MainWindow extends Application {
     private ChangeListener<Number> filterChangeListener;
 
     public static void main(String[] args) {
+        // The embedded OpenGL canvas (openglfx) breaks JavaFX's partial-repaint accounting, leaving
+        // sibling controls (e.g. the log panel) with a stale background. Disabling Prism's dirty-region
+        // optimization forces a full scene repaint each pulse, which fixes the artifacts. Must be set
+        // before the JavaFX toolkit initializes.
+        System.setProperty("prism.dirtyopts", "false");
         setLocaleFromSettings();
         ArgumentParser argParser = new ArgumentParser(args);
         inputFile = CityDoctorValidation.getInputFile(argParser, true);
@@ -302,7 +293,7 @@ public class MainWindow extends Application {
         FXMLLoader loader = new FXMLLoader(MainWindow.class.getResource("MainWindow.fxml"));
         loader.setController(this);
         BorderPane bp = loader.load();
-        highlightController = new HighlightController(world);
+        highlightController = new HighlightController(glViewport);
         renderer = new Renderer(this, highlightController);
         clickHandler = new VertexClickHandler(errorView, renderer, stage, this);
         controller = new CityDoctorController(this, highlightController, renderer);
@@ -820,8 +811,11 @@ public class MainWindow extends Application {
         MenuItem deleteOption = new MenuItem(Localization.getText("MainWindow.delete"));
         deleteOption.setOnAction(ae -> controller.delete(featureView.getSelectionModel().getSelectedItem()));
         menu.getItems().add(deleteOption);
-        featureView.setContextMenu(menu);
+
      */
+
+        featureView.setContextMenu(menu);
+
     }
 
     public void fetchCopyAction(Renderable node) {
@@ -842,36 +836,31 @@ public class MainWindow extends Application {
     }
 
     private void setup3dView() {
-        Group root = new Group();
-        geomScene = new SubScene(root, 500, 300, true, SceneAntialiasing.BALANCED);
-        geomScene.heightProperty().bind(meshView.heightProperty());
-        geomScene.widthProperty().bind(meshView.widthProperty());
-        geomScene.setFill(Color.AZURE);
-        meshView.getChildren().add(geomScene);
-
-        geomScene.addEventFilter(MouseEvent.MOUSE_PRESSED, me -> {
+        glViewport = new GLViewport();
+        Region canvas = glViewport.getNode();
+        canvas.prefWidthProperty().bind(meshView.widthProperty());
+        canvas.prefHeightProperty().bind(meshView.heightProperty());
+        meshView.getChildren().add(canvas);
+
+        canvas.addEventFilter(MouseEvent.MOUSE_PRESSED, me -> {
             clickStart[0] = me.getScreenX();
             clickStart[1] = me.getScreenY();
         });
 
-        geomScene.addEventFilter(MouseEvent.MOUSE_RELEASED, me -> {
+        canvas.addEventFilter(MouseEvent.MOUSE_RELEASED, me -> {
             if (Math.abs(clickStart[0] - me.getScreenX()) > 3 || Math.abs(clickStart[1] - me.getScreenY()) > 3) {
                 // skip when mouse moved too much
                 return;
             }
-            Node node = me.getPickResult().getIntersectedNode();
-            if (node != null) {
-                Object o = node.getUserData();
-                if (o instanceof ClickDispatcher cd) {
-                    cd.click(me, clickHandler);
+            glViewport.requestPick(me.getX(), me.getY(), target -> {
+                if (target instanceof Polygon p) {
+                    new PolygonClickDispatcher(p).click(me, clickHandler);
                 }
-            }
+            });
         });
 
-        world = new Group();
-        root.getChildren().add(world);
-        meshGroup = new Group();
-        world.getChildren().add(meshGroup);
+        // keep the north arrow aligned with the camera after orbit drags
+        canvas.addEventFilter(MouseEvent.MOUSE_DRAGGED, me -> alignNorthArrow());
 
         north = new Image(getClass().getResourceAsStream("icons/north.png"), 50, 50, true, true);
         northFlip = new Image(getClass().getResourceAsStream("icons/north_flip.png"), 50, 50, true, true);
@@ -882,81 +871,13 @@ public class MainWindow extends Application {
         northArrow.setY(10);
         meshView.getChildren().add(northArrow);
         northArrow.setVisible(false);
-
-        AmbientLight al = new AmbientLight(Color.WHITE);
-        root.getChildren().add(al);
-        buildCamera();
-        cameraXRotation.setAxis(Rotate.X_AXIS);
-        cameraZRotation.setAxis(Rotate.Z_AXIS);
-        world.getTransforms().add(cameraXRotation);
-        world.getTransforms().add(cameraZRotation);
-        root.getChildren().add(camera);
-        geomScene.setCamera(camera);
-
-        setupMeshViewControls();
-    }
-
-    private void setupMeshViewControls() {
-        meshView.setOnMousePressed(me -> {
-            if (me.getButton() == MouseButton.PRIMARY) {
-                dragX = me.getScreenX();
-                dragY = me.getScreenY();
-            }
-            if (me.getButton() == MouseButton.SECONDARY) {
-                dragX = me.getScreenX();
-                dragY = me.getScreenY();
-            }
-        });
-
-        meshView.setOnScroll(se -> {
-            if (se.getDeltaY() < 0) {
-                translateZ += translateZ * 0.05;
-            } else {
-                translateZ -= translateZ * 0.05;
-            }
-            camera.setTranslateZ(translateZ);
-            highlightController.changeScaling(translateZ);
-        });
-
-        meshView.setOnMouseDragged(me -> {
-            if (me.getButton() == MouseButton.PRIMARY) {
-                double deltaX = me.getScreenX() - dragX;
-                double deltaY = me.getScreenY() - dragY;
-                dragX = me.getScreenX();
-                dragY = me.getScreenY();
-
-                cameraXRot += (deltaX / 3d) % 360;
-                cameraYRot += (deltaY / 3d) % 360;
-
-                cameraZRotation.setAngle(cameraXRot);
-                cameraXRotation.setAngle(cameraYRot);
-                alignNorthArrow();
-            }
-            if (me.getButton() == MouseButton.SECONDARY) {
-                double translationSpeed = Math.abs(camera.getTranslateZ()) / 1000;
-                double deltaX = me.getScreenX() - dragX;
-                double deltaY = me.getScreenY() - dragY;
-                dragX = me.getScreenX();
-                dragY = me.getScreenY();
-
-                camera.setTranslateX(camera.getTranslateX() - deltaX * translationSpeed);
-                camera.setTranslateY(camera.getTranslateY() - deltaY * translationSpeed);
-            }
-        });
-    }
-
-    private void buildCamera() {
-        camera = new PerspectiveCamera(true);
-        camera.setNearClip(0.1);
-        camera.setFarClip(10000d);
-        camera.setTranslateZ(translateZ);
-        cameraZRotation.setAngle(cameraXRot);
-        cameraXRotation.setAngle(cameraYRot);
     }
 
     public void alignNorthArrow() {
-        double absRotZ = cameraZRotation.getAngle() - 360 * Math.floor(cameraZRotation.getAngle() / 360);
-        double absRotX = cameraXRotation.getAngle() - 360 * Math.floor(cameraXRotation.getAngle() / 360);
+        double azimuth = glViewport.camera().azimuthDeg();
+        double elevation = glViewport.camera().elevationDeg();
+        double absRotZ = azimuth - 360 * Math.floor(azimuth / 360);
+        double absRotX = elevation - 360 * Math.floor(elevation / 360);
 
         double northRot;
         if (80 <= absRotX && absRotX <= 260) {
@@ -975,16 +896,11 @@ public class MainWindow extends Application {
     }
 
     public void resetCamera() {
-        cameraXRot = CAMERA_INITIAL_X_ANGLE;
-        cameraYRot = CAMERA_INITIAL_Y_ANGLE;
-        cameraZRotation.setAngle(cameraXRot);
-        cameraXRotation.setAngle(cameraYRot);
-        alignNorthArrow();
-        camera.setTranslateX(0);
-        camera.setTranslateY(0);
+        glViewport.resetCamera();
         if (controller.getOriginBB() != null) {
             zoomOutForBoundingBox(controller.getOriginBB());
         }
+        alignNorthArrow();
     }
 
     public void addFileNameToTitle(String fileName) {
@@ -1052,8 +968,14 @@ public class MainWindow extends Application {
         return mainToolBar.getGridButton();
     }
 
-    public Group getMeshGroup() {
-        return meshGroup;
+    public GLViewport getGlViewport() {
+        return glViewport;
+    }
+
+    /** Clears whatever geometry is currently displayed in the 3D view. */
+    public void clearMeshView() {
+        glViewport.setScene(null);
+        glViewport.setIndexSet(new int[0]);
     }
 
     public ToggleButton getCullingButton() {
@@ -1134,20 +1056,16 @@ public class MainWindow extends Application {
     }
 
     public void takeViewScreenshot() throws IOException {
-        WritableImage snapshot = geomScene.snapshot(null, null);
+        WritableImage snapshot = glViewport.getNode().snapshot(null, null);
         File outputFile = new File("img.png");
         BufferedImage bImage = SwingFXUtils.fromFXImage(snapshot, null);
         ImageIO.write(bImage, "png", outputFile);
     }
 
     public void zoomOutForBoundingBox(BoundingBox b) {
-        double longestSide = b.getDiagonalLength() * 0.4;
-        double d = longestSide / Math.tan(Math.toRadians(30) / 2);
-        translateZ = -d;
-        camera.setTranslateZ(translateZ);
-        camera.setTranslateX(0);
-        camera.setTranslateY(0);
-        highlightController.changeScaling(-translateZ);
+        glViewport.camera().zoomOutForBoundingBox(b.getDiagonalLength());
+        glViewport.getNode().repaint();
+        highlightController.changeScaling(glViewport.camera().distance());
         controller.setOriginBB(b);
     }
 

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/Renderer.java

@@ -4,7 +4,6 @@ import de.hft.stuttgart.citydoctor2.check.CheckError;
 import de.hft.stuttgart.citydoctor2.check.Checkable;
 import de.hft.stuttgart.citydoctor2.utils.visitors.CityObjectCollector;
 import de.hft.stuttgart.citydoctor2.datastructure.*;
-import de.hft.stuttgart.citydoctor2.gui.filter.ViewFilter;
 import de.hft.stuttgart.citydoctor2.gui.tree.*;
 import de.hft.stuttgart.citydoctor2.gui.tree.node.EdgeNode;
 import de.hft.stuttgart.citydoctor2.gui.tree.node.ErrorNode;
@@ -12,12 +11,15 @@ import de.hft.stuttgart.citydoctor2.gui.tree.node.GenericAttributeNode;
 import de.hft.stuttgart.citydoctor2.gui.tree.node.LinearRingNode;
 import de.hft.stuttgart.citydoctor2.gui.tree.node.PolygonNode;
 import de.hft.stuttgart.citydoctor2.gui.tree.node.VertexNode;
+import de.hft.stuttgart.citydoctor2.gui.gl.GLViewport;
+import de.hft.stuttgart.citydoctor2.gui.gl.IndexSetBuilder;
+import de.hft.stuttgart.citydoctor2.gui.gl.SceneBuilder;
+import de.hft.stuttgart.citydoctor2.gui.gl.SceneData;
+import de.hft.stuttgart.citydoctor2.gui.gl.TriangleMeta;
 import de.hft.stuttgart.citydoctor2.math.Triangle3d;
 import javafx.application.Platform;
 import javafx.scene.control.TreeItem;
 import javafx.scene.paint.Color;
-import javafx.scene.shape.CullFace;
-import javafx.scene.shape.DrawMode;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -28,11 +30,15 @@ public class Renderer {
 
     private static final Logger logger = LogManager.getLogger(Renderer.class);
 
-    private TriangulatedGeometry currentTriGeom;
+    private SceneData currentScene;
     private Geometry currentGeometry;
 
-    private CullFace currentCulling = CullFace.NONE;
-    private DrawMode currentDrawMode = DrawMode.FILL;
+    private boolean culling = false;
+    private boolean wireframe = false;
+
+    // LOD visibility, indexed by Lod.ordinal() (LOD0..LOD4); all enabled by default
+    private final boolean[] lodEnabled = {true, true, true, true, true};
+    private boolean roofsHidden = false;
 
     private MainWindow mainWindow;
     private HighlightController highlightController;
@@ -40,8 +46,6 @@ public class Renderer {
 
     private LoadingInfoDialog loadingDialog;
 
-    private List<ViewFilter> lodFilters = new ArrayList<>();
-    private ViewFilter roofFilter;
     private Runnable refresher;
     private Runnable errorUpdater;
 
@@ -50,138 +54,74 @@ public class Renderer {
         this.highlightController = highlightController;
         loadingDialog = new LoadingInfoDialog(mainWindow.getMainStage());
         errVisitor = new ListErrorVisitor(highlightController);
-        setupLodFilters();
     }
 
-    private void setupLodFilters() {
-        lodFilters.add(new ViewFilter() {
-
-            @Override
-            public boolean useGeometry(CityObject co, Geometry geom) {
-                return geom.getLod() == Lod.LOD1;
-            }
-
-        });
-        lodFilters.add(new ViewFilter() {
-
-            @Override
-            public boolean useGeometry(CityObject co, Geometry geom) {
-                return geom.getLod() == Lod.LOD2;
-            }
-
-        });
-        lodFilters.add(new ViewFilter() {
-
-            @Override
-            public boolean useGeometry(CityObject co, Geometry geom) {
-                return geom.getLod() == Lod.LOD3;
-            }
-
-        });
-        lodFilters.add(new ViewFilter() {
-
-            @Override
-            protected boolean useGeometry(CityObject co, Geometry geom) {
-                return geom.getLod() == Lod.LOD0;
-            }
-
-        });
-        lodFilters.add(new ViewFilter() {
-
-            @Override
-            public boolean useGeometry(CityObject co, Geometry geom) {
-                return geom.getLod() == Lod.LOD4;
-            }
-        });
-        roofFilter = new ViewFilter() {
-            @Override
-            public boolean allowedToUse(CityObject co, Geometry geom) {
-                if (!this.isEnabled()) {
-                    return true;
-                }
-                return this.useGeometry(co, geom);
-            }
-
-            @Override
-            public boolean useGeometry(CityObject co, Geometry geom) {
-                if (co instanceof BoundarySurface bs) {
-                    return bs.getType() != BoundarySurfaceType.ROOF;
-                }
-                return true;
-            }
+    private boolean triangleVisible(TriangleMeta m) {
+        int lod = m.lod();
+        boolean lodOk = lod < 0 || lod >= lodEnabled.length || lodEnabled[lod];
+        if (!lodOk) {
+            return false;
+        }
+        return !roofsHidden || !m.roof();
+    }
 
-        };
-        roofFilter.setEnable(false);
+    private void rebuildIndexSet() {
+        if (currentScene == null) {
+            return;
+        }
+        mainWindow.getGlViewport().setIndexSet(
+                IndexSetBuilder.build(currentScene.triangleMetas(), this::triangleVisible));
     }
 
     public void enableLod1() {
-        lodFilters.get(0).enable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD1.ordinal(), true);
     }
 
     public void disableLod1() {
-        lodFilters.get(0).disable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD1.ordinal(), false);
     }
 
     public void enableLod2() {
-        lodFilters.get(1).enable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD2.ordinal(), true);
     }
 
     public void disableLod2() {
-        lodFilters.get(1).disable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD2.ordinal(), false);
     }
 
     public void enableLod3() {
-        lodFilters.get(2).enable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD3.ordinal(), true);
     }
 
     public void disableLod3() {
-        lodFilters.get(2).disable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD3.ordinal(), false);
     }
 
     public void enableLod4() {
-        lodFilters.get(3).enable();
-        if (refresher != null) {
-            refresher.run();
-        }
+        setLodEnabled(Lod.LOD4.ordinal(), true);
     }
 
     public void disableLod4() {
-        lodFilters.get(3).disable();
-        if (refresher != null) {
-            refresher.run();
+        setLodEnabled(Lod.LOD4.ordinal(), false);
+    }
+
+    private void setLodEnabled(int lodOrdinal, boolean enabled) {
+        // legacy LOD0 followed LOD3 button; keep LOD0 tied to LOD3 toggle for parity
+        lodEnabled[lodOrdinal] = enabled;
+        if (lodOrdinal == Lod.LOD3.ordinal()) {
+            lodEnabled[Lod.LOD0.ordinal()] = enabled;
         }
+        Platform.runLater(this::rebuildIndexSet);
     }
 
     public void hideRoofs() {
-        roofFilter.setEnable(true);
-        if (refresher != null) {
-            refresher.run();
-        }
+        roofsHidden = true;
+        Platform.runLater(this::rebuildIndexSet);
     }
 
     public void showRoofs() {
-        roofFilter.setEnable(false);
-        if (refresher != null) {
-            refresher.run();
-        }
+        roofsHidden = false;
+        Platform.runLater(this::rebuildIndexSet);
     }
 
     public void setupRefresher(CityObject co) {
@@ -207,18 +147,7 @@ public class Renderer {
 
     private void addPolygons(CityObject co, Set<ConcretePolygon> polygons) {
         for (Geometry geom : co.getGeometries()) {
-            boolean used = false;
-            for (ViewFilter filter : lodFilters) {
-                if (filter.allowedToUse(co, geom)) {
-                    used = true;
-                    break;
-                }
-            }
-            if (used) {
-                if (roofFilter.allowedToUse(co, geom)) {
-                    addConcretePolygons(polygons, geom);
-                }
-            }
+            addConcretePolygons(polygons, geom);
         }
     }
 
@@ -244,15 +173,14 @@ public class Renderer {
     public void render(Geometry geom) {
         refresher = () -> {
             Platform.runLater(this::clearGeometryTrees);
-            currentTriGeom = TriangulatedGeometry.of(geom);
+            SceneData scene = SceneBuilder.fromPolygons(geom.getPolygons(), Color.WHITE);
             if (geom.getEdges() == null && currentGeometry != null) {
                 // if there are no edges available low memory mode is enabled
                 // clear the old geometry of all meta information
                 currentGeometry.clearMetaData();
             }
-            errVisitor.setGeometry(currentTriGeom);
             Platform.runLater(() -> {
-                setupRenderState();
+                applyScene(scene);
                 if (geom.getEdges() == null) {
                     // create edges and vertices so they can be listed in the gui
                     geom.prepareForChecking();
@@ -349,9 +277,8 @@ public class Renderer {
 
     private void render(Collection<? extends Polygon> polygons) {
         Platform.runLater(this::clearGeometryTrees);
-        currentTriGeom = TriangulatedGeometry.of(polygons);
-        errVisitor.setGeometry(currentTriGeom);
-        setupRenderState();
+        SceneData scene = SceneBuilder.fromPolygons(polygons, Color.WHITE);
+        Platform.runLater(() -> applyScene(scene));
     }
 
     private void clearGeometryTrees() {
@@ -375,10 +302,9 @@ public class Renderer {
                 clearAttributes();
             });
             Thread t = new Thread(() -> {
-                currentTriGeom = TriangulatedGeometry.of(model, lodFilters);
-                errVisitor.setGeometry(currentTriGeom);
+                SceneData scene = SceneBuilder.fromModel(model);
                 Platform.runLater(() -> {
-                    setupRenderState();
+                    applyScene(scene);
                     mainWindow.zoomOutForBoundingBox(BoundingBox.of(model));
                     loadingDialog.hide();
                 });
@@ -430,14 +356,10 @@ public class Renderer {
                 CityObjectCollector collector = new CityObjectCollector();
                 cos.forEach(cityObject -> cityObject.accept(collector));
                 collector.getCityObjects().forEach(cityObject -> addPolygons(cityObject, polygons));
-                if (baseColor != null) {
-                    currentTriGeom = TriangulatedGeometry.of(polygons, baseColor);
-                } else {
-                    currentTriGeom = TriangulatedGeometry.of(polygons);
-                }
-                errVisitor.setGeometry(currentTriGeom);
+                Color base = baseColor != null ? baseColor : Color.WHITE;
+                SceneData scene = SceneBuilder.fromPolygons(polygons, base);
                 Platform.runLater(() -> {
-                    setupRenderState();
+                    applyScene(scene);
                     mainWindow.zoomOutForBoundingBox(BoundingBox.of(polygons));
                     loadingDialog.hide();
                 });
@@ -455,49 +377,44 @@ public class Renderer {
 
     private void addConcretePolygons(Set<ConcretePolygon> polygons, Geometry geom) {
         for (Polygon p : geom.getPolygons()) {
-            if (p.getOriginal().getPartOfSurface() != null &&
-                    !roofFilter.allowedToUse(p.getOriginal().getPartOfSurface(), p.getParent())) continue;
             polygons.add(p.getOriginal());
         }
     }
 
-    private void setupRenderState() {
-        currentTriGeom.setCullFace(currentCulling);
-        currentTriGeom.setDrawMode(currentDrawMode);
-        Platform.runLater(() -> {
-            mainWindow.getMeshGroup().getChildren().clear();
-            mainWindow.getMeshGroup().getChildren().addAll(currentTriGeom.getMeshes());
-        });
+    /**
+     * Installs the freshly built scene into the viewport (FX thread), wires the highlight center
+     * supplier, applies the current wireframe/cull state and rebuilds the visible index set.
+     */
+    private void applyScene(SceneData scene) {
+        currentScene = scene;
+        GLViewport viewport = mainWindow.getGlViewport();
+        viewport.setScene(scene);
+        highlightController.setCenterSupplier(
+                () -> currentScene == null ? new double[3] : currentScene.center());
+        viewport.setWireframe(wireframe);
+        viewport.setCulling(culling);
+        rebuildIndexSet();
         mainWindow.getGridButton().setDisable(false);
         mainWindow.getCullingButton().setDisable(false);
     }
 
     public void showWireFrame(boolean show) {
-        if (currentTriGeom != null) {
-            if (show) {
-                currentDrawMode = DrawMode.LINE;
-            } else {
-                currentDrawMode = DrawMode.FILL;
-            }
-            currentTriGeom.setDrawMode(currentDrawMode);
-        }
+        wireframe = show;
+        mainWindow.getGlViewport().setWireframe(show);
     }
 
     public void enableCulling(boolean enable) {
-        if (currentTriGeom != null) {
-            if (enable) {
-                currentCulling = CullFace.BACK;
-            } else {
-                currentCulling = CullFace.NONE;
-            }
-            currentTriGeom.setCullFace(currentCulling);
-        }
+        culling = enable;
+        mainWindow.getGlViewport().setCulling(enable);
     }
 
     public void clearCurrentRender() {
         // don't render anything
+        currentScene = null;
         Platform.runLater(() -> {
-            mainWindow.getMeshGroup().getChildren().clear();
+            GLViewport viewport = mainWindow.getGlViewport();
+            viewport.setScene(null);
+            viewport.setIndexSet(new int[0]);
             clearGeometryTrees();
             clearAttributes();
         });
@@ -508,35 +425,35 @@ public class Renderer {
     }
 
     public void highlight(Polygon p) {
-        highlightController.highlight(p, currentTriGeom);
+        highlightController.highlight(p);
     }
 
     public void highlight(LinearRing lr) {
-        highlightController.highlight(lr, currentTriGeom);
+        highlightController.highlight(lr);
     }
 
     public void highlight(Edge e) {
-        highlightController.highlight(e, currentTriGeom);
+        highlightController.highlight(e);
     }
 
     public void highlight(Vertex v) {
-        highlightController.highlight(v, currentTriGeom);
+        highlightController.highlight(v);
     }
 
     public void highlight(List<LinearRing> highlightedRings) {
-        highlightController.highlight(highlightedRings, currentTriGeom);
+        highlightController.highlight(highlightedRings);
     }
 
     public void highlightEdges(List<Edge> edges) {
-        highlightController.highlightEdges(edges, currentTriGeom);
+        highlightController.highlightEdges(edges);
     }
 
     public void highlightPolygons(List<List<Polygon>> components) {
-        highlightController.highlightPolygons(components, currentTriGeom);
+        highlightController.highlightPolygons(components);
     }
 
     public void addHighlight(Vertex vertex, Color c) {
-        highlightController.addHighlight(vertex, currentTriGeom, c);
+        highlightController.addHighlight(vertex, c);
     }
 
     public void highlight(CheckError err) {
@@ -560,11 +477,11 @@ public class Renderer {
     }
 
     public void addHighlight(Polygon p) {
-        highlightController.addHighlight(p, currentTriGeom);
+        highlightController.addHighlight(p);
     }
 
     public void addHighlight(Triangle3d t) {
-        highlightController.highlight(t, currentTriGeom);
+        highlightController.highlight(t);
     }
 
     public void reset() {

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/TriangulatedGeometry.java

-package de.hft.stuttgart.citydoctor2.gui;
-
-import de.hft.stuttgart.citydoctor2.utils.visitors.CityObjectCollector;
-import de.hft.stuttgart.citydoctor2.datastructure.Polygon;
-import de.hft.stuttgart.citydoctor2.datastructure.*;
-import de.hft.stuttgart.citydoctor2.gui.filter.ViewFilter;
-import de.hft.stuttgart.citydoctor2.math.Triangle3d;
-import de.hft.stuttgart.citydoctor2.math.UnitVector3d;
-import de.hft.stuttgart.citydoctor2.math.Vector3d;
-import de.hft.stuttgart.citydoctor2.tesselation.TesselatedPolygon;
-import javafx.scene.paint.Color;
-import javafx.scene.paint.PhongMaterial;
-import javafx.scene.shape.*;
-
-import java.util.*;
-import java.util.stream.Stream;
-
-public class TriangulatedGeometry {
-
-	private static final PhongMaterial GRID_MAT = new PhongMaterial(Color.BLACK);
-
-	// random vector for calculating normal angles, for color determination
-	private static final UnitVector3d AXIS = new Vector3d(19, 0.8, 1.5).normalize();
-
-	private Vector3d movedBy;
-	private List<MeshView> meshes;
-	private List<PhongMaterial> materials;
-	
-	public static TriangulatedGeometry of(Geometry geom) {
-		return of(geom.getPolygons());
-	}
-	
-	public static TriangulatedGeometry of(Collection<? extends Polygon> polygons, Color basePolygonColor) {
-		TriangulatedGeometry triGeom = new TriangulatedGeometry();
-		triGeom.materials = new ArrayList<>();
-		triGeom.meshes = new ArrayList<>();
-		List<Vector3d> points = new ArrayList<>();
-		for (Polygon p : polygons) {
-            points.addAll(p.getExteriorRing().getVertices());
-		}
-		triGeom.movedBy = triGeom.findCenter(points);
-		
-		addPolygonDataToTriGeom(polygons, basePolygonColor, triGeom);
-		return triGeom;
-	}
-
-	private static void addPolygonDataToTriGeom(Collection<? extends Polygon> polygons, Color basePolygonColor,
-			TriangulatedGeometry triGeom) {
-		for (Polygon p : polygons) {
-			TesselatedPolygon tp = p.tesselate();
-			TriangleMesh triMesh = new TriangleMesh(VertexFormat.POINT_TEXCOORD);
-			Map<Vector3d, Integer> indexMap = new HashMap<>();
-			List<Vector3d> vertices = new ArrayList<>();
-			int index = 0;
-			for (Triangle3d t : tp.getTriangles()) {
-				index = triGeom.filterDuplicates(triMesh, indexMap, vertices, index, t.getP1());
-				index = triGeom.filterDuplicates(triMesh, indexMap, vertices, index, t.getP2());
-				index = triGeom.filterDuplicates(triMesh, indexMap, vertices, index, t.getP3());
-			}
-			
-			for (Vector3d point : vertices) {
-				float x = (float) (point.getX() - triGeom.movedBy.getX());
-				float y = (float) (point.getY() - triGeom.movedBy.getY());
-				float z = (float) (point.getZ() - triGeom.movedBy.getZ());
-				triMesh.getPoints().addAll(x, y, z);
-			}
-			triMesh.getTexCoords().addAll(0, 0);
-
-			MeshView view = new MeshView(triMesh);
-			view.setUserData(new PolygonClickDispatcher(p));
-
-			PhongMaterial mat = triGeom.calculateMaterial(p, basePolygonColor);
-			triGeom.materials.add(mat);
-			triGeom.meshes.add(view);
-		}
-	}
-	
-	public static TriangulatedGeometry of(CityDoctorModel model, List<ViewFilter> filters) {
-		List<Vector3d> points = new ArrayList<>();
-		addPointsFromCityObject(model.createFeatureStream().toList(), points);
-		
-		TriangulatedGeometry triGeom = new TriangulatedGeometry();
-		triGeom.materials = new ArrayList<>();
-		triGeom.meshes = new ArrayList<>();
-		triGeom.movedBy = triGeom.findCenter(points);
-
-		addPolygonDataFromCityObjects(model.getBuildings(), triGeom, Color.WHITE, filters);
-		addPolygonDataFromCityObjects(model.getBridges(), triGeom, Color.LIGHTSTEELBLUE, filters);
-		addPolygonDataFromCityObjects(model.getTunnels(), triGeom, Color.SLATEGRAY, filters);
-		addPolygonDataFromCityObjects(model.getLand(), triGeom, Color.TAN, filters);
-		addPolygonDataFromCityObjects(model.getTransportation(), triGeom, Color.DIMGRAY, filters);
-		addPolygonDataFromCityObjects(model.getVegetation(), triGeom, Color.LIGHTGREEN, filters);
-		addPolygonDataFromCityObjects(model.getWater(), triGeom, Color.LIGHTSKYBLUE, filters);
-		addPolygonDataFromCityObjects(model.getCityFurniture(), triGeom, Color.BLUEVIOLET, filters);
-		addPolygonDataFromCityObjects(model.getOtherCityObjects(), triGeom, Color.BLACK, filters);
-		
-		return triGeom;
-	}
-
-
-
-	private static void addPolygonDataFromCityObjects(Stream<? extends CityObject> cos,
-													  TriangulatedGeometry triGeom, Color color, List<ViewFilter> filters) {
-		CityObjectCollector collector = new CityObjectCollector();
-		cos.forEach(cityObject -> cityObject.accept(collector));
-		collector.getCityObjects().forEach(cityObject -> addPolygonData(cityObject, triGeom, color, filters));
-	}
-
-	private static void addPolygonData(CityObject co, TriangulatedGeometry triGeom, Color color, List<ViewFilter> filters) {
-		for (Geometry geom : co.getGeometries()) {
-			if (isGeometryFiltered(co, geom, filters)) {
-				continue;
-			}
-			List<Polygon> polygons = new ArrayList<>();
-			for (Polygon p : geom.getPolygons()) {
-				if (p.isLink()) {
-					continue;
-				}
-				polygons.add(p);
-			}
-			addPolygonDataToTriGeom(polygons, color, triGeom);
-		}
-	}
-	
-	private static boolean isGeometryFiltered(CityObject co, Geometry geom, List<ViewFilter> filters) {
-		for (ViewFilter filter : filters) {
-			if (filter.allowedToUse(co, geom)) {
-				return false;
-			}
-		}
-		return true;
-	}
-
-	private static void addPointsFromCityObject(List<? extends CityObject> cos, List<Vector3d> points) {
-		CityObjectCollector collector = new CityObjectCollector();
-		cos.forEach(cityObject -> cityObject.accept(collector));
-		collector.getCityObjects().forEach(cityObject -> addPoints(cityObject, points));
-	}
-
-	private static void addPoints(CityObject co, List<Vector3d> points) {
-		for (Geometry geom : co.getGeometries()) {
-			for (Polygon p : geom.getPolygons()) {
-				if (p.isLink()) {
-					continue;
-				}
-                points.addAll(p.getExteriorRing().getVertices());
-			}
-		}
-	}
-
-	public static TriangulatedGeometry of(Collection<? extends Polygon> polygons) {
-		return of(polygons, Color.WHITE);
-	}
-
-	private int filterDuplicates(TriangleMesh triMesh, Map<Vector3d, Integer> indexMap, List<Vector3d> vertices,
-			int index, Vector3d v) {
-		Integer vertexIndex = indexMap.get(v);
-		if (vertexIndex == null) {
-			indexMap.put(v, index);
-			vertices.add(v);
-			vertexIndex = index;
-			index++;
-		}
-		triMesh.getFaces().addAll(vertexIndex, 0);
-		return index;
-	}
-
-	private PhongMaterial calculateMaterial(Polygon p, Color baseColor) {
-		Vector3d normal = p.calculateNormalNormalized();
-
-		if (p.getRenderColor() != null && p.getRenderColor() != Color.WHITE) {
-			baseColor = p.getRenderColor();
-		}
-
-		double cos = normal.dot(AXIS);
-		double acos = Math.acos(cos);
-		// normalize to range [0.3, 0.9]
-		acos = acos / Math.PI;
-		acos = acos * 0.6 + 0.3;
-
-		Color derivedColor = baseColor.deriveColor(0, 1.0, acos, 1.0);
-		return new PhongMaterial(derivedColor);
-	}
-
-
-	private Vector3d findCenter(List<Vector3d> points) {
-		double xMin = Double.MAX_VALUE;
-		double yMin = Double.MAX_VALUE;
-		double zMin = Double.MAX_VALUE;
-
-		double xMax = Double.NEGATIVE_INFINITY;
-		double yMax = Double.NEGATIVE_INFINITY;
-		double zMax = Double.NEGATIVE_INFINITY;
-
-		for (Vector3d point : points) {
-			if (point.getX() < xMin) {
-				xMin = point.getX();
-			}
-			if (point.getX() > xMax) {
-				xMax = point.getX();
-			}
-			if (point.getY() < yMin) {
-				yMin = point.getY();
-			}
-			if (point.getY() > yMax) {
-				yMax = point.getY();
-			}
-			if (point.getZ() < zMin) {
-				zMin = point.getZ();
-			}
-			if (point.getZ() > zMax) {
-				zMax = point.getZ();
-			}
-		}
-
-		// center
-		double x = (xMax - xMin) / 2 + xMin;
-		double y = (yMax - yMin) / 2 + yMin;
-		double z = (zMax - zMin) / 2 + zMin;
-		return new Vector3d(x, y, z);
-	}
-
-	public Vector3d getMovedBy() {
-		return movedBy;
-	}
-
-	public void setCullFace(CullFace currentCulling) {
-		for (MeshView mesh : meshes) {
-			mesh.setCullFace(currentCulling);
-		}
-	}
-
-	public void setDrawMode(DrawMode currentDrawMode) {
-		if (currentDrawMode == DrawMode.LINE) {
-			for (MeshView mesh : meshes) {
-				mesh.setDrawMode(currentDrawMode);
-				mesh.setMaterial(GRID_MAT);
-			}
-		} else if (currentDrawMode == DrawMode.FILL) {
-			for (int i = 0; i < meshes.size(); i++) {
-				MeshView mesh = meshes.get(i);
-				mesh.setDrawMode(currentDrawMode);
-				mesh.setMaterial(materials.get(i));
-			}
-		}
-	}
-
-	public List<MeshView> getMeshes() {
-		return meshes;
-	}
-}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ValidationView.java

@@ -46,7 +46,7 @@ public class ValidationView extends View {
 	public void onHide() {
 		Platform.runLater(() -> {
 			mainWindow.unselectEverything();
-			mainWindow.getMeshGroup().getChildren().clear();
+			mainWindow.clearMeshView();
 			mainWindow.clearHighlights();
 			mainWindow.getErrorTree().getRoot().getChildren().clear();
 			mainWindow.getPolygonsView().getRoot().getChildren().clear();

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/FloatList.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import java.util.Arrays;
+
+/** Growable primitive float array to avoid boxing when building large vertex buffers. */
+public class FloatList {
+    private float[] data;
+    private int size;
+
+    public FloatList() { this(1024); }
+    public FloatList(int initialCapacity) { data = new float[Math.max(1, initialCapacity)]; }
+
+    public void add(float v) {
+        ensure(size + 1);
+        data[size++] = v;
+    }
+
+    public void add(float a, float b, float c) {
+        ensure(size + 3);
+        data[size++] = a;
+        data[size++] = b;
+        data[size++] = c;
+    }
+
+    private void ensure(int capacity) {
+        if (capacity > data.length) {
+            int newCap = data.length;
+            while (newCap < capacity) {
+                newCap <<= 1;
+            }
+            data = Arrays.copyOf(data, newCap);
+        }
+    }
+
+    public int size() { return size; }
+
+    /** Resets the list to empty without releasing the backing array. */
+    public void clear() { size = 0; }
+
+    public float[] toArray() { return Arrays.copyOf(data, size); }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/GLViewport.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import com.huskerdev.grapl.gl.GLProfile;
+import com.huskerdev.openglfx.canvas.GLCanvas;
+import com.huskerdev.openglfx.jogl.JOGLExecutor;
+import com.huskerdev.openglfx.jogl.events.JOGLRenderEvent;
+import com.jogamp.opengl.GL;
+import com.jogamp.opengl.GL3;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Consumer;
+import javafx.animation.AnimationTimer;
+import javafx.application.Platform;
+import javafx.scene.input.MouseButton;
+import javafx.scene.paint.Color;
+
+/** OpenGL viewport embedded in JavaFX via openglfx. Replaces the legacy SubScene. */
+public class GLViewport {
+
+    private static final Color BACKGROUND = Color.AZURE;
+
+    private final GLCanvas canvas;
+    private final OrbitCamera camera = new OrbitCamera();
+    private final GlScene scene = new GlScene();
+    private final PickingFramebuffer picking = new PickingFramebuffer();
+    private final HighlightOverlay overlay = new HighlightOverlay();
+
+    private ShaderProgram sceneProgram;
+    private ShaderProgram pickProgram;
+    private ShaderProgram pointProgram;
+    private boolean initialized;
+
+    // state set off-thread, consumed in render callback
+    private final AtomicReference<SceneData> pendingScene = new AtomicReference<>();
+    private final AtomicReference<int[]> pendingIndexSet = new AtomicReference<>();
+    // last index set seen; retained so it can be (re)applied after the scene is uploaded or the GL
+    // context is recreated (the index buffer only exists once the scene's buffers have been generated)
+    private volatile int[] lastIndices;
+    private volatile boolean wireframe = false;
+    private volatile boolean cull = false;
+    private volatile float pointScale = 20f;
+    private volatile float lineScale = 4f;
+
+    // highlight marker data, uploaded on the GL thread when dirty
+    private volatile float[] hlPoints = new float[0];
+    private volatile float[] hlPointColors = new float[0];
+    private volatile float[] hlLines = new float[0];
+    private volatile float[] hlLineColors = new float[0];
+    private volatile boolean highlightsDirty = false;
+
+    // pick request: logical (JavaFX) screen coords + callback (invoked on FX thread with resolved Object)
+    private volatile double[] pickRequest;
+    private volatile Consumer<Object> pickCallback;
+    private SceneData currentScene;
+
+    // drag state
+    private double lastX;
+    private double lastY;
+
+    // optional hook invoked after a camera interaction (orbit/pan/zoom) so a coupled viewport can be
+    // kept in sync and redrawn (used by the dual-viewport healer)
+    private Runnable interactionListener;
+
+    // on-demand render request. openglfx can drop a repaint() that arrives while a frame is rendering
+    // (its requestRepaint is an unconditional notify with no pending flag), so a single repaint is not
+    // reliable. This flag + pump re-deliver repaint() each pulse until a frame consumes the request,
+    // then the pump stops itself so an idle viewport has no per-pulse cost.
+    private volatile boolean renderRequested;
+    private final AnimationTimer repaintPump = new AnimationTimer() {
+        @Override
+        public void handle(long now) {
+            if (renderRequested) {
+                canvas.repaint();
+            } else {
+                stop();
+            }
+        }
+    };
+
+    public GLViewport() {
+        // args: executor, profile, flipY=false, msaa=4, fps=0.0
+        // fps=0 -> on-demand rendering: a frame is drawn only when repaint() is called (every state
+        // change / input does so), so an idle viewport allocates and renders nothing.
+        canvas = new GLCanvas(new JOGLExecutor(), GLProfile.CORE, false, 4, 0.0);
+        canvas.addOnInitEvent(ev -> {
+            // GL context (re)created: shaders/buffers from any previous context are gone. Drop our
+            // handles and re-queue the current scene so it is re-uploaded into the new context.
+            initialized = false;
+            scene.markContextLost();
+            if (currentScene != null) {
+                pendingScene.set(currentScene);
+            }
+        });
+        canvas.addOnRenderEvent(ev -> render((JOGLRenderEvent) ev));
+        canvas.addOnReshapeEvent(ev -> { /* aspect handled per-frame from width/height */ });
+        // on-demand mode: repaint when the canvas is resized so the framebuffer tracks the new size
+        canvas.widthProperty().addListener((obs, ov, nv) -> requestRender());
+        canvas.heightProperty().addListener((obs, ov, nv) -> requestRender());
+        installInputHandlers();
+    }
+
+    public GLCanvas getNode() { return canvas; }
+
+    // ---- public API (called from FX / worker threads) ----
+
+    public void setScene(SceneData data) { pendingScene.set(data); requestRender(); }
+
+    public void setIndexSet(int[] indices) { pendingIndexSet.set(indices); requestRender(); }
+
+    public void setWireframe(boolean on) { wireframe = on; requestRender(); }
+
+    public void setCulling(boolean on) { cull = on; requestRender(); }
+
+    public void setPointScale(float scale) { pointScale = scale; requestRender(); }
+
+    /** points: xyz, pointColors rgb-per-point; lines: xyz pairs, lineColors rgb-per-line-vertex. */
+    public void setHighlights(float[] points, float[] pointColors, float[] lines, float[] lineColors) {
+        this.hlPoints = points;
+        this.hlPointColors = pointColors;
+        this.hlLines = lines;
+        this.hlLineColors = lineColors;
+        this.highlightsDirty = true;
+        requestRender();
+    }
+
+    public OrbitCamera camera() { return camera; }
+
+    /** Hook invoked after a camera interaction so a coupled viewport can sync and redraw. */
+    public void setInteractionListener(Runnable listener) { this.interactionListener = listener; }
+
+    /** Public redraw trigger (e.g. for a coupled viewport). */
+    public void requestRedraw() { requestRender(); }
+
+    /** Clears the displayed geometry (draws nothing) until a new scene is set. */
+    public void clearScene() {
+        currentScene = null;
+        lastIndices = new int[0];
+        setIndexSet(new int[0]);
+    }
+
+    /**
+     * Requests a redraw. Sets the render flag, wakes the canvas immediately (best effort), and starts
+     * the pump so the request is re-delivered until a frame actually consumes it. Call on the FX thread.
+     */
+    private void requestRender() {
+        renderRequested = true;
+        canvas.repaint();
+        repaintPump.start(); // idempotent while running
+    }
+
+    public void requestPick(double x, double y, Consumer<Object> callback) {
+        pickRequest = new double[]{x, y};
+        pickCallback = callback;
+        requestRender();
+    }
+
+    // ---- render callback (GL thread) ----
+
+    private void render(JOGLRenderEvent ev) {
+        // consume the render request; if new state arrives during this frame, requestRender re-arms it
+        renderRequested = false;
+        GL3 gl = ev.getGl();
+        int w = ev.width;
+        int h = ev.height;
+        int defaultFbo = ev.fbo;
+
+        if (!initialized) {
+            sceneProgram = new ShaderProgram(gl, "scene.vert", "scene.frag");
+            pickProgram = new ShaderProgram(gl, "pick.vert", "pick.frag");
+            pointProgram = new ShaderProgram(gl, "point.vert", "point.geom", "point.frag");
+            overlay.init(gl);
+            gl.glEnable(GL.GL_DEPTH_TEST);
+            gl.glEnable(GL.GL_MULTISAMPLE); // anti-aliasing for the multisampled framebuffer
+            initialized = true;
+        }
+
+        SceneData newScene = pendingScene.getAndSet(null);
+        boolean uploadedNow = false;
+        if (newScene != null) {
+            scene.upload(gl, newScene);
+            currentScene = newScene;
+            uploadedNow = true;
+        }
+        int[] newIndices = pendingIndexSet.getAndSet(null);
+        if (newIndices != null) {
+            lastIndices = newIndices;
+        }
+        // Apply the index set only once the scene's buffers exist (the element buffer is created by
+        // upload). Re-apply after a fresh upload so the indices survive a scene swap or context loss.
+        if (scene.hasData() && lastIndices != null && (newIndices != null || uploadedNow)) {
+            scene.setIndexSet(gl, lastIndices);
+        }
+        if (highlightsDirty) {
+            overlay.setPoints(gl, hlPoints, hlPointColors);
+            overlay.setLines(gl, hlLines, hlLineColors);
+            highlightsDirty = false;
+        }
+
+        camera.setAspect(h == 0 ? 1f : (float) w / h);
+        float[] mvp = camera.viewProjection();
+
+        gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, defaultFbo);
+        gl.glViewport(0, 0, w, h);
+        gl.glClearColor((float) BACKGROUND.getRed(), (float) BACKGROUND.getGreen(),
+                (float) BACKGROUND.getBlue(), 1f);
+        gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
+        if (cull) {
+            gl.glEnable(GL.GL_CULL_FACE);
+        } else {
+            gl.glDisable(GL.GL_CULL_FACE);
+        }
+        gl.glPolygonMode(GL.GL_FRONT_AND_BACK, wireframe ? GL3.GL_LINE : GL3.GL_FILL);
+
+        sceneProgram.use(gl);
+        gl.glUniformMatrix4fv(sceneProgram.uniform(gl, "uMVP"), 1, false, mvp, 0);
+        scene.draw(gl);
+        // wireframe applies to the geometry only; highlight markers always render filled
+        gl.glPolygonMode(GL.GL_FRONT_AND_BACK, GL3.GL_FILL);
+        // highlight markers sit at the same depth as geometry edges (and the wireframe lines); use
+        // LEQUAL so the later-drawn markers win depth ties instead of being rejected by GL_LESS
+        gl.glDepthFunc(GL.GL_LEQUAL);
+        // edge markers reuse the flat scene program (pos + colour)
+        overlay.drawLines(gl, lineScale);
+        // vertex markers use the sphere-impostor program (geometry shader -> camera-facing quads)
+        pointProgram.use(gl);
+        gl.glUniformMatrix4fv(pointProgram.uniform(gl, "uMVP"), 1, false, mvp, 0);
+        gl.glUniform2f(pointProgram.uniform(gl, "uViewport"), (float) w, (float) h);
+        gl.glUniform1f(pointProgram.uniform(gl, "uPointSize"), pointScale);
+        overlay.drawPoints(gl);
+        gl.glDepthFunc(GL.GL_LESS); // restore for the next frame's scene pass
+
+        double[] req = pickRequest;
+        if (req != null && currentScene != null) {
+            picking.resize(gl, w, h);
+            picking.bind(gl);
+            gl.glClearColor(0, 0, 0, 1);
+            gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
+            gl.glPolygonMode(GL.GL_FRONT_AND_BACK, GL3.GL_FILL);
+            pickProgram.use(gl);
+            gl.glUniformMatrix4fv(pickProgram.uniform(gl, "uMVP"), 1, false, mvp, 0);
+            scene.draw(gl);
+            // click coords are logical (JavaFX) px; the picking buffer is physical px. Scale by the
+            // framebuffer/canvas ratio so HiDPI displays read the pixel actually under the cursor.
+            double cw = canvas.getWidth();
+            double ch = canvas.getHeight();
+            float sx = cw > 0 ? (float) (w / cw) : 1f;
+            float sy = ch > 0 ? (float) (h / ch) : 1f;
+            int px = Math.round((float) req[0] * sx);
+            int py = Math.round((float) req[1] * sy);
+            int id = picking.readId(gl, px, py);
+            Object target = currentScene.pickRegistry().resolve(id);
+            Consumer<Object> cb = pickCallback;
+            pickRequest = null;
+            pickCallback = null;
+            gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, defaultFbo);
+            if (cb != null) {
+                Platform.runLater(() -> cb.accept(target));
+            }
+        }
+    }
+
+    // ---- input ----
+
+    private void installInputHandlers() {
+        canvas.setOnMousePressed(e -> { lastX = e.getX(); lastY = e.getY(); });
+        canvas.setOnMouseDragged(e -> {
+            double dx = e.getX() - lastX;
+            double dy = e.getY() - lastY;
+            lastX = e.getX();
+            lastY = e.getY();
+            if (e.getButton() == MouseButton.PRIMARY) {
+                camera.orbit(dx / 3.0, dy / 3.0);
+            } else if (e.getButton() == MouseButton.SECONDARY) {
+                double speed = Math.abs(camera.distance()) / 1000.0;
+                camera.pan(-dx * speed, dy * speed);
+            }
+            requestRender();
+            notifyInteraction();
+        });
+        canvas.setOnScroll(e -> {
+            camera.zoom(e.getDeltaY() < 0 ? 1.05 : 0.95);
+            requestRender();
+            notifyInteraction();
+        });
+    }
+
+    public void resetCamera() { camera.reset(); requestRender(); }
+
+    private void notifyInteraction() {
+        if (interactionListener != null) {
+            interactionListener.run();
+        }
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/GlScene.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import com.jogamp.opengl.GL;
+import com.jogamp.opengl.GL3;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+
+/** GPU resources for the global scene mesh. Single VBO (pos+color+id), one index buffer redrawn per frame. */
+public class GlScene {
+
+    private int vao = 0;
+    private int vboPos;
+    private int vboColor;
+    private int vboId;
+    private int ebo;
+    private int indexCount;
+    private boolean uploaded;
+
+    public void upload(GL3 gl, SceneData data) {
+        if (!uploaded) {
+            int[] ids = new int[3];
+            gl.glGenVertexArrays(1, ids, 0);
+            vao = ids[0];
+            int[] buffers = new int[4];
+            gl.glGenBuffers(4, buffers, 0);
+            vboPos = buffers[0];
+            vboColor = buffers[1];
+            vboId = buffers[2];
+            ebo = buffers[3];
+        }
+        gl.glBindVertexArray(vao);
+
+        uploadFloat(gl, vboPos, data.positions(), 0, 3);
+        uploadFloat(gl, vboColor, data.colors(), 1, 3);
+        uploadInt(gl, vboId, data.ids(), 2);
+
+        gl.glBindVertexArray(0);
+        uploaded = true;
+    }
+
+    private void uploadFloat(GL3 gl, int vbo, float[] data, int location, int components) {
+        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vbo);
+        FloatBuffer fb = toFloatBuffer(data);
+        gl.glBufferData(GL.GL_ARRAY_BUFFER, (long) data.length * Float.BYTES, fb, GL.GL_STATIC_DRAW);
+        gl.glEnableVertexAttribArray(location);
+        gl.glVertexAttribPointer(location, components, GL.GL_FLOAT, false, 0, 0L);
+    }
+
+    private void uploadInt(GL3 gl, int vbo, int[] data, int location) {
+        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vbo);
+        IntBuffer ib = toIntBuffer(data);
+        gl.glBufferData(GL.GL_ARRAY_BUFFER, (long) data.length * Integer.BYTES, ib, GL.GL_STATIC_DRAW);
+        gl.glEnableVertexAttribArray(location);
+        gl.glVertexAttribIPointer(location, 1, GL3.GL_INT, 0, 0L); // integer attribute, not normalized
+    }
+
+    /** Re-uploads which triangles to draw (element indices). Cheap; called on filter/LOD changes. */
+    public void setIndexSet(GL3 gl, int[] indices) {
+        if (!uploaded || vao == 0) {
+            // buffers not generated yet; the caller re-applies once the scene is uploaded
+            return;
+        }
+        gl.glBindVertexArray(vao);
+        gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, ebo);
+        IntBuffer ib = toIntBuffer(indices);
+        gl.glBufferData(GL.GL_ELEMENT_ARRAY_BUFFER, (long) indices.length * Integer.BYTES, ib,
+                GL.GL_DYNAMIC_DRAW);
+        gl.glBindVertexArray(0);
+        indexCount = indices.length;
+    }
+
+    public void draw(GL3 gl) {
+        if (vao == 0 || indexCount == 0) {
+            return;
+        }
+        gl.glBindVertexArray(vao);
+        gl.glDrawElements(GL.GL_TRIANGLES, indexCount, GL.GL_UNSIGNED_INT, 0L);
+        gl.glBindVertexArray(0);
+    }
+
+    public boolean hasData() { return uploaded; }
+
+    /**
+     * Forgets GL handles after the context was lost/recreated, without issuing GL calls (the old
+     * handles belong to a dead context). The next {@link #upload} regenerates everything.
+     */
+    public void markContextLost() {
+        vao = 0;
+        indexCount = 0;
+        uploaded = false;
+    }
+
+    public void dispose(GL3 gl) {
+        if (vao != 0) {
+            gl.glDeleteVertexArrays(1, new int[]{vao}, 0);
+            gl.glDeleteBuffers(4, new int[]{vboPos, vboColor, vboId, ebo}, 0);
+            vao = 0;
+            uploaded = false;
+        }
+    }
+
+    private static FloatBuffer toFloatBuffer(float[] data) {
+        ByteBuffer bb = ByteBuffer.allocateDirect(data.length * Float.BYTES).order(ByteOrder.nativeOrder());
+        FloatBuffer fb = bb.asFloatBuffer();
+        fb.put(data).flip();
+        return fb;
+    }
+
+    private static IntBuffer toIntBuffer(int[] data) {
+        ByteBuffer bb = ByteBuffer.allocateDirect(data.length * Integer.BYTES).order(ByteOrder.nativeOrder());
+        IntBuffer ib = bb.asIntBuffer();
+        ib.put(data).flip();
+        return ib;
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/HighlightOverlay.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import com.jogamp.opengl.GL;
+import com.jogamp.opengl.GL3;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+
+/**
+ * Dynamic overlay for highlight markers: points for vertices, lines for edges. Positions are in the same
+ * recentred world space as the scene. Colour rides in the color attribute; id attribute is 0.
+ */
+public class HighlightOverlay {
+
+    private int pointVao;
+    private int pointPos;
+    private int pointColor;
+    private int pointId;
+    private int pointCount;
+
+    private int lineVao;
+    private int linePos;
+    private int lineColor;
+    private int lineId;
+    private int lineVertexCount;
+
+    private boolean created;
+
+    public void init(GL3 gl) {
+        int[] v = new int[2];
+        gl.glGenVertexArrays(2, v, 0);
+        pointVao = v[0];
+        lineVao = v[1];
+        int[] b = new int[6];
+        gl.glGenBuffers(6, b, 0);
+        pointPos = b[0]; pointColor = b[1]; pointId = b[2];
+        linePos = b[3]; lineColor = b[4]; lineId = b[5];
+        created = true;
+    }
+
+    /** points: xyz triplets; pointColors: rgb triplets (one per point). */
+    public void setPoints(GL3 gl, float[] points, float[] pointColors) {
+        pointCount = points.length / 3;
+        configure(gl, pointVao, pointPos, points, pointColor, pointColors, pointId, pointCount);
+    }
+
+    /** lines: xyz pairs of endpoints (6 floats per segment); lineColors: rgb per line vertex. */
+    public void setLines(GL3 gl, float[] lines, float[] lineColors) {
+        lineVertexCount = lines.length / 3;
+        configure(gl, lineVao, linePos, lines, lineColor, lineColors, lineId, lineVertexCount);
+    }
+
+    private void configure(GL3 gl, int vao, int posVbo, float[] pos, int colVbo, float[] col,
+                           int idVbo, int vertexCount) {
+        gl.glBindVertexArray(vao);
+        bindFloat(gl, posVbo, pos, 0, 3);
+        bindFloat(gl, colVbo, col, 1, 3);
+        // id attribute all zeros so overlay never matches uSelectedId
+        int[] zeros = new int[vertexCount];
+        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, idVbo);
+        gl.glBufferData(GL.GL_ARRAY_BUFFER, (long) zeros.length * Integer.BYTES, toInt(zeros),
+                GL.GL_DYNAMIC_DRAW);
+        gl.glEnableVertexAttribArray(2);
+        gl.glVertexAttribIPointer(2, 1, GL3.GL_INT, 0, 0L);
+        gl.glBindVertexArray(0);
+    }
+
+    private void bindFloat(GL3 gl, int vbo, float[] data, int loc, int comp) {
+        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vbo);
+        gl.glBufferData(GL.GL_ARRAY_BUFFER, (long) data.length * Float.BYTES, toFloat(data),
+                GL.GL_DYNAMIC_DRAW);
+        gl.glEnableVertexAttribArray(loc);
+        gl.glVertexAttribPointer(loc, comp, GL.GL_FLOAT, false, 0, 0L);
+    }
+
+    /** Draws the edge markers as lines. The caller must bind a program that reads pos+color. */
+    public void drawLines(GL3 gl, float lineWidth) {
+        if (!created || lineVertexCount == 0) {
+            return;
+        }
+        gl.glLineWidth(lineWidth);
+        gl.glBindVertexArray(lineVao);
+        gl.glDrawArrays(GL.GL_LINES, 0, lineVertexCount);
+        gl.glBindVertexArray(0);
+    }
+
+    /**
+     * Draws the vertex markers as GL_POINTS. The caller must bind the sphere-impostor program (a
+     * geometry shader expands each point into a camera-facing quad shaded as a sphere).
+     */
+    public void drawPoints(GL3 gl) {
+        if (!created || pointCount == 0) {
+            return;
+        }
+        gl.glBindVertexArray(pointVao);
+        gl.glDrawArrays(GL.GL_POINTS, 0, pointCount);
+        gl.glBindVertexArray(0);
+    }
+
+    public void clear() {
+        pointCount = 0;
+        lineVertexCount = 0;
+    }
+
+    private static FloatBuffer toFloat(float[] d) {
+        FloatBuffer fb = ByteBuffer.allocateDirect(Math.max(1, d.length) * Float.BYTES)
+                .order(ByteOrder.nativeOrder()).asFloatBuffer();
+        fb.put(d).flip();
+        return fb;
+    }
+
+    private static IntBuffer toInt(int[] d) {
+        IntBuffer ib = ByteBuffer.allocateDirect(Math.max(1, d.length) * Integer.BYTES)
+                .order(ByteOrder.nativeOrder()).asIntBuffer();
+        ib.put(d).flip();
+        return ib;
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/IndexSetBuilder.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import java.util.List;
+import java.util.function.Predicate;
+
+/** Builds the element index set (triangle vertex indices) for the triangles passing the filter. */
+public final class IndexSetBuilder {
+
+    private IndexSetBuilder() {}
+
+    public static int[] build(List<TriangleMeta> metas, Predicate<TriangleMeta> include) {
+        IntList out = new IntList();
+        for (TriangleMeta m : metas) {
+            if (include.test(m)) {
+                int base = m.triangleIndex() * 3;
+                out.add(base);
+                out.add(base + 1);
+                out.add(base + 2);
+            }
+        }
+        return out.toArray();
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/IntList.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import java.util.Arrays;
+
+/** Growable primitive int array. */
+public class IntList {
+    private int[] data;
+    private int size;
+
+    public IntList() { this(1024); }
+    public IntList(int initialCapacity) { data = new int[Math.max(1, initialCapacity)]; }
+
+    public void add(int v) {
+        if (size + 1 > data.length) {
+            data = Arrays.copyOf(data, data.length << 1);
+        }
+        data[size++] = v;
+    }
+
+    public int get(int index) { return data[index]; }
+
+    public int size() { return size; }
+
+    public int[] toArray() { return Arrays.copyOf(data, size); }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/Mat4.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+/**
+ * Minimal column-major 4x4 float matrix helpers, layout-compatible with OpenGL uniform uploads
+ * (element index = column*4 + row).
+ */
+public final class Mat4 {
+
+    private Mat4() {}
+
+    public static float[] identity() {
+        float[] m = new float[16];
+        m[0] = m[5] = m[10] = m[15] = 1f;
+        return m;
+    }
+
+    public static float[] translation(float x, float y, float z) {
+        float[] m = identity();
+        m[12] = x;
+        m[13] = y;
+        m[14] = z;
+        return m;
+    }
+
+    /** Returns a * b (column-major). */
+    public static float[] multiply(float[] a, float[] b) {
+        float[] r = new float[16];
+        for (int col = 0; col < 4; col++) {
+            for (int row = 0; row < 4; row++) {
+                float sum = 0f;
+                for (int k = 0; k < 4; k++) {
+                    sum += a[k * 4 + row] * b[col * 4 + k];
+                }
+                r[col * 4 + row] = sum;
+            }
+        }
+        return r;
+    }
+
+    /** Returns m * (x,y,z,w) as a length-4 array. */
+    public static float[] transform(float[] m, float x, float y, float z, float w) {
+        return new float[] {
+            m[0] * x + m[4] * y + m[8]  * z + m[12] * w,
+            m[1] * x + m[5] * y + m[9]  * z + m[13] * w,
+            m[2] * x + m[6] * y + m[10] * z + m[14] * w,
+            m[3] * x + m[7] * y + m[11] * z + m[15] * w
+        };
+    }
+
+    public static float[] rotationX(float rad) {
+        float c = (float) Math.cos(rad);
+        float s = (float) Math.sin(rad);
+        float[] m = identity();
+        m[5] = c;  m[9]  = -s;
+        m[6] = s;  m[10] = c;
+        return m;
+    }
+
+    public static float[] rotationZ(float rad) {
+        float c = (float) Math.cos(rad);
+        float s = (float) Math.sin(rad);
+        float[] m = identity();
+        m[0] = c;  m[4] = -s;
+        m[1] = s;  m[5] = c;
+        return m;
+    }
+
+    /** Right-handed perspective projection (camera looks down -Z). */
+    public static float[] perspective(float fovyRad, float aspect, float near, float far) {
+        float f = (float) (1.0 / Math.tan(fovyRad / 2.0));
+        float[] m = new float[16];
+        m[0] = f / aspect;
+        m[5] = f;
+        m[10] = (far + near) / (near - far);
+        m[11] = -1f;
+        m[14] = (2f * far * near) / (near - far);
+        return m;
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/MeshAccumulator.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import de.hft.stuttgart.citydoctor2.math.Triangle3d;
+import de.hft.stuttgart.citydoctor2.math.Vector3d;
+
+/**
+ * Builds interleaved-by-attribute vertex arrays from triangles. Vertices are stored per triangle corner
+ * (3 per triangle) so a triangle's vertices occupy a contiguous, predictable range — which lets the
+ * draw index set be built by triangle without dedup bookkeeping.
+ */
+public class MeshAccumulator {
+
+    private final Vector3d center;
+    private final FloatList positions = new FloatList();
+    private final FloatList colors = new FloatList();
+    private final IntList ids = new IntList();
+    private int vertexCount;
+
+    public MeshAccumulator(Vector3d center) {
+        this.center = center;
+    }
+
+    public void addTriangle(Triangle3d t, int id, float r, float g, float b) {
+        addVertex(t.getP1(), id, r, g, b);
+        addVertex(t.getP2(), id, r, g, b);
+        addVertex(t.getP3(), id, r, g, b);
+    }
+
+    private void addVertex(Vector3d p, int id, float r, float g, float b) {
+        positions.add((float) (p.getX() - center.getX()),
+                      (float) (p.getY() - center.getY()),
+                      (float) (p.getZ() - center.getZ()));
+        colors.add(r, g, b);
+        ids.add(id);
+        vertexCount++;
+    }
+
+    public int vertexCount() { return vertexCount; }
+
+    public float[] positions() { return positions.toArray(); }
+
+    public float[] colors() { return colors.toArray(); }
+
+    public int[] ids() { return ids.toArray(); }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/OrbitCamera.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+/**
+ * Orbit camera reproducing the legacy JavaFX interaction model: world is rotated about Z then X, the
+ * camera sits at {@code distance} along -Z (negative distance = farther away) and pans in X/Y.
+ */
+public class OrbitCamera {
+
+    private static final double INITIAL_AZIMUTH = 180.0;
+    private static final double INITIAL_ELEVATION = -60.0;
+    private static final double INITIAL_DISTANCE = 100.0;
+    private static final double FOVY_RAD = Math.toRadians(30);
+    private static final float NEAR = 0.1f;
+    private static final float FAR = 10000f;
+
+    private double azimuthDeg = INITIAL_AZIMUTH;
+    private double elevationDeg = INITIAL_ELEVATION;
+    private double distance = INITIAL_DISTANCE;
+    private double panX = 0;
+    private double panY = 0;
+    private float aspect = 1.0f;
+
+    public void setAspect(float aspect) {
+        if (aspect > 0) {
+            this.aspect = aspect;
+        }
+    }
+
+    public void orbit(double deltaAzimuthDeg, double deltaElevationDeg) {
+        azimuthDeg += deltaAzimuthDeg;
+        elevationDeg += deltaElevationDeg;
+    }
+
+    public void pan(double dx, double dy) {
+        panX += dx;
+        panY += dy;
+    }
+
+    /** factor > 1 moves farther, < 1 moves closer. */
+    public void zoom(double factor) {
+        distance *= factor;
+    }
+
+    /** Matches legacy MainWindow.zoomOutForBoundingBox distance computation. */
+    public void zoomOutForBoundingBox(double diagonalLength) {
+        double longestSide = diagonalLength * 0.4;
+        distance = longestSide / Math.tan(FOVY_RAD / 2.0);
+        panX = 0;
+        panY = 0;
+    }
+
+    public void reset() {
+        azimuthDeg = INITIAL_AZIMUTH;
+        elevationDeg = INITIAL_ELEVATION;
+        distance = INITIAL_DISTANCE;
+        panX = 0;
+        panY = 0;
+    }
+
+    /** Copies the orbit/zoom/pan state from another camera (but not its aspect ratio). */
+    public void copyOrbitFrom(OrbitCamera other) {
+        this.azimuthDeg = other.azimuthDeg;
+        this.elevationDeg = other.elevationDeg;
+        this.distance = other.distance;
+        this.panX = other.panX;
+        this.panY = other.panY;
+    }
+
+    public double distance() { return distance; }
+
+    /** Current azimuth (rotation about Z) in degrees. */
+    public double azimuthDeg() { return azimuthDeg; }
+
+    /** Current elevation (rotation about X) in degrees. */
+    public double elevationDeg() { return elevationDeg; }
+
+    /** Combined projection * view * model-rotation, column-major, ready for a GL uniform. */
+    public float[] viewProjection() {
+        float[] proj = Mat4.perspective((float) FOVY_RAD, aspect, NEAR, FAR);
+        float[] view = Mat4.translation((float) -panX, (float) -panY, (float) -distance);
+        float[] rot = Mat4.multiply(
+                Mat4.rotationX((float) Math.toRadians(elevationDeg)),
+                Mat4.rotationZ((float) Math.toRadians(azimuthDeg)));
+        return Mat4.multiply(proj, Mat4.multiply(view, rot));
+    }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/PickRegistry.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Maps picking ids (1-based) to the model objects they represent. */
+public class PickRegistry {
+
+    private final List<Object> targets = new ArrayList<>();
+
+    /** Registers a target and returns its non-zero picking id. */
+    public int register(Object target) {
+        targets.add(target);
+        return targets.size(); // id = index + 1
+    }
+
+    /** Resolves a picking id to its target, or null for background / unknown id. */
+    public Object resolve(int id) {
+        if (id <= 0 || id > targets.size()) {
+            return null;
+        }
+        return targets.get(id - 1);
+    }
+
+    public int size() { return targets.size(); }
+}

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/gl/PickingCodec.java

+package de.hft.stuttgart.citydoctor2.gui.gl;
+
+/** Encodes integer ids into RGB bytes for GPU color-picking. Id 0 is reserved for background. */
+public final class PickingCodec {
+
+    private PickingCodec() {}
+
+    public static int red(int id)   { return id & 0xFF; }
+    public static int green(int id) { return (id >> 8) & 0xFF; }
+    public static int blue(int id)  { return (id >> 16) & 0xFF; }
+
+    public static int decode(int r, int g, int b) {
+        return (r & 0xFF) | ((g & 0xFF) << 8) | ((b & 0xFF) << 16);
+    }
+}