Is there a way to show uv from meshview to flat drawing in javafx?

Question

is there a way to show uv coords on gui like blender blender uv ?

Answer 1

Displaying uv coordinates to path

There is no built in gui object , but we can create a custom one with paths . We can retrieve uv indices from faces[] in mesh object and get its values in texcoords[]

This is a single javafx app you can try . as far as i know there is no way to get mesh instance from a Shape3D object , so this works for trianglefaces custom mesh in meshview object only . I can't set mesh.fxml 'cause it will overflow char limit .

App.java

public class App extends Application {
    
    @Override
    public void start(Stage stage) throws IOException {
        Image uvImage = new Image("/uv.jpg");
        
        PerspectiveCamera pc = new PerspectiveCamera(true);
        pc.setTranslateZ(-6);
        MeshView mv = loadMeshView();
        PhongMaterial pm = new PhongMaterial();
        pm.setDiffuseMap(uvImage);
        mv.setMaterial(pm);
        Group group3d = new Group(pc, mv);
        
        RotateTransition animation = new RotateTransition(Duration.seconds(4), mv);
         animation.setInterpolator(Interpolator.LINEAR);
        animation.setAxis(Rotate.Y_AXIS);
        animation.setByAngle(360);
        animation.setCycleCount(100);
       
        
        animation.play();
        SubScene subScene = new SubScene(group3d, 400, 400, true, SceneAntialiasing.BALANCED);
        subScene.setFill(Color.AQUAMARINE);
        subScene.setCamera(pc);
        
        ImageView imageView = new ImageView(uvImage);
        imageView.setFitHeight(400);
        imageView.setFitWidth(400);
        Group groupUv = new Group(imageView);
        
        makeUvLines(groupUv, mv);
        Text u = new Text("U");
        Text v = new Text("V");
        v.setTranslateY(200);
        v.setTranslateX(-20);
        u.setTranslateX(200);
        u.setTranslateY(420);
        
        Line uLine = new Line(0, 0, 0, 400);
        Polygon uArrow = new Polygon(0, 0, 8, 8, -8, 8);
        Polygon vArrow = new Polygon(400, 400, 392, 408, 392, 392);
        
        Line vLine = new Line(0, 400, 400, 400);
        
        Pane ap = new Pane(groupUv, uLine, vLine, uArrow, vArrow, u, v);
        ap.setPrefSize(400, 400);
        ap.setMaxSize(400, 400);
        ap.setStyle("-fx-background-color:yellow");
        HBox.setHgrow(ap, Priority.NEVER);
        
        HBox hb = new HBox(subScene, ap);
        hb.setSpacing(30);
        hb.setAlignment(Pos.CENTER);
        
        var scene = new Scene(hb, 800, 600);
        stage.setTitle("JavaFX UV Visualizer");
        stage.setScene(scene);
        stage.show();
    }
    
    public static void main(String[] args) {
        launch();
    }
    
    private void makeUvLines(Group groupUv, MeshView meshView) {
        TriangleMesh mesh = (TriangleMesh) meshView.getMesh();
        
        int[] faces = mesh.getFaces().toArray(new int[mesh.getFaces().size()]);
        float[] texCoords = mesh.getTexCoords().toArray(new float[mesh.getTexCoords().size()]);
        
        for (int i = 0; i < faces.length; i++) {
            float scale = 400;
            float startU = texCoords[2 * faces[i + 1]];
            float startV = texCoords[((2 * faces[i + 1]) + 1)];
            
            float u1 = texCoords[2 * faces[i + 3]];
            float v1 = texCoords[((2 * faces[i + 3]) + 1)];
            
            float endU = texCoords[2 * faces[i + 5]];
            float endV = texCoords[((2 * faces[i + 5]) + 1)];
            
            Path p = new Path(
                    new MoveTo(startU * scale, startV * scale),
                    new LineTo(u1 * scale, v1 * scale),
                    new LineTo(endU * scale, endV * scale),
                    new ClosePath()
            );
            p.setStroke(Color.ORANGE);
            p.setFill(Color.color(0.1, 0.3, 0.1, 0.7));
            groupUv.getChildren().add(p);
            
            i += 5;
        }        
        
    }
    
    private MeshView loadMeshView() throws IOException {
        FXMLLoader loader = new FXMLLoader(App.class.getResource("/mesh.fxml"));
        loader.load();
        MeshView meshView = loader.getRoot();
        
        return meshView;
    }
    
}

uv.jpg