java - 对于 3d 星场(在 JavaFX 中),使标签与查看者的视角保持一致

标签 java javafx javafx-11 openjfx

注意 :我找到了一个解决方案并编辑了这个例子来展示如何做到这一点。我将把这段代码移到我更大的应用程序中。
我编写了一个 3d 恒星图表应用程序,它接收 GAIA 恒星数据并向您显示 3d 表示。您可以根据查询的属性查询和绘制一组恒星对象。此应用程序旨在帮助科幻小说作家和爱好者将空间区域中的真实关系可视化。
当我构建 View 时,我绘制了代表星星的球体(半径、颜色等)。
我标记了这些星星中的每一个,以便用户可以识别感兴趣的星星。
所以我的问题是,当我旋转 View (实际上是相机)时,标签会转动,用户会发现这很不方便。那么如何在旋转 View 时让它们面向相机呢?
一些细节。我保留两组。一个是绘制的所有星星,一个是标签。星星和标签都绘制在同一点上。单独组的原因是能够独立于星星打开和关闭标签(可用性问题)。
因此,当我旋转视野时,我想取一组标签并将每个标签转换为面向相机。
示例:(茎从赤道平面投影到恒星,网格映射赤道平面用于透视)
enter image description here
随着 View 的转变:
enter image description here
这是工作示例。我找到了一个 FXyz 库示例并将其更改为我想要的。 FXyz 中唯一使用的是 Mathutils.clamp(...)。

import javafx.application.Application;
import javafx.application.Platform;
import javafx.geometry.Point3D;
import javafx.scene.*;
import javafx.scene.control.Label;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.Background;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.text.Font;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;

import java.util.HashMap;
import java.util.Random;

import static org.fxyz3d.geometry.MathUtils.clamp;

/**
 * example for floating labels
 */
public class StarFieldExample extends Application {

    final double sceneWidth = 600;
    final double sceneHeight = 600;

    private double mousePosX;
    private double mousePosY;
    private double mouseOldX;
    private double mouseOldY;
    private double mouseDeltaX;
    private double mouseDeltaY;

    private final Font font = new Font("arial", 10);

    // We'll use custom Rotate transforms to manage the coordinate conversions
    private final Rotate rotateX = new Rotate(0, Rotate.X_AXIS);
    private final Rotate rotateY = new Rotate(0, Rotate.Y_AXIS);
    private final Rotate rotateZ = new Rotate(0, Rotate.Z_AXIS);

    private final Group root = new Group();
    private final Group nodeGroup = new Group();  //all 3D nodes in scene
    private final Group labelGroup = new Group(); //all generic 3D labels

    //All shapes and labels linked via hash for easy update during camera movement
    private final HashMap<Shape3D, Label> shape3DToLabel = new HashMap<>();

    private SubScene subScene;

    private final Random random = new Random();

    private final static double RADIUS_MAX = 7;
    private final static double X_MAX = 300;
    private final static double Y_MAX = 300;
    private final static double Z_MAX = 300;

    public Pane createStarField() {

        //attach our custom rotation transforms so we can update the labels dynamically
        nodeGroup.getTransforms().addAll(rotateX, rotateY, rotateZ);

        subScene = new SubScene(nodeGroup, sceneWidth, sceneHeight, true, SceneAntialiasing.BALANCED);
        subScene.setFill(Color.BLACK);

        PerspectiveCamera camera = new PerspectiveCamera(true);
        camera.setNearClip(0.1);
        camera.setFarClip(10000.0);
        camera.setTranslateZ(-1000);

        subScene.setCamera(camera);
        Group sceneRoot = new Group(subScene);
        sceneRoot.getChildren().add(labelGroup);

        generateRandomStars(20);

        subScene.setOnMousePressed((MouseEvent me) -> {
                    mousePosX = me.getSceneX();
                    mousePosY = me.getSceneY();
                    mouseOldX = me.getSceneX();
                    mouseOldY = me.getSceneY();
                }
        );

        subScene.setOnMouseDragged((MouseEvent me) -> {
                    mouseOldX = mousePosX;
                    mouseOldY = mousePosY;
                    mousePosX = me.getSceneX();
                    mousePosY = me.getSceneY();
                    mouseDeltaX = (mousePosX - mouseOldX);
                    mouseDeltaY = (mousePosY - mouseOldY);
                    double modifier = 5.0;
                    double modifierFactor = 0.1;

                    if (me.isPrimaryButtonDown()) {
                        if (me.isAltDown()) { //roll
                            rotateZ.setAngle(((rotateZ.getAngle() + mouseDeltaX * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180); // +
                        } else {
                            rotateY.setAngle(((rotateY.getAngle() + mouseDeltaX * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180); // +
                            rotateX.setAngle(
                                    clamp(
                                            (((rotateX.getAngle() - mouseDeltaY * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180),
                                            -60,
                                            60
                                    )
                            ); // -
                        }
                    }
                    updateLabels();
                }
        );

        // add to the 2D portion of this component
        Pane pane = new Pane();
        pane.setPrefSize(sceneWidth, sceneHeight);
        pane.setMaxSize(Pane.USE_COMPUTED_SIZE, Pane.USE_COMPUTED_SIZE);
        pane.setMinSize(Pane.USE_COMPUTED_SIZE, Pane.USE_COMPUTED_SIZE);
        pane.setBackground(Background.EMPTY);
        pane.getChildren().add(sceneRoot);
        pane.setPickOnBounds(false);

        subScene.widthProperty().bind(pane.widthProperty());
        subScene.heightProperty().bind(pane.heightProperty());
        Platform.runLater(this::updateLabels);
        return (pane);
    }

    public void generateRandomStars(int numberStars) {
        for (int i = 0; i < numberStars; i++) {
            double radius = random.nextDouble() * RADIUS_MAX;
            Color color = randomColor();
            double x = random.nextDouble() * X_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);
            double y = random.nextDouble() * Y_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);
            double z = random.nextDouble() * Z_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);

            String labelText = "Star " + i;
            boolean fadeFlag = random.nextBoolean();
            createSphereLabel(radius, x, y, z, color, labelText);
        }
    }

    private Color randomColor() {
        int r = random.nextInt(255);
        int g = random.nextInt(255);
        int b = random.nextInt(255);
        return Color.rgb(r, g, b);
    }


    private void createSphereLabel(double radius, double x, double y, double z, Color color, String labelText) {
        Sphere sphere = new Sphere(radius);
        sphere.setTranslateX(x);
        sphere.setTranslateY(y);
        sphere.setTranslateZ(z);
        sphere.setMaterial(new PhongMaterial(color));
        //add our nodes to the group that will later be added to the 3D scene
        nodeGroup.getChildren().add(sphere);

        Label label = new Label(labelText);
        label.setTextFill(color);
        label.setFont(font);
        labelGroup.getChildren().add(label);

        //Add to hashmap so updateLabels() can manage the label position
        shape3DToLabel.put(sphere, label);
    }

    private void updateLabels() {
        shape3DToLabel.forEach((node, label) -> {
            Point3D coordinates = node.localToScene(Point3D.ZERO, true);

            //Clipping Logic
            //if coordinates are outside of the scene it could
            //stretch the screen so don't transform them
            double x = coordinates.getX();
            double y = coordinates.getY();

            // is it left of the view?
            if (x < 0) {
                x = 0;
            }

            // is it right of the view?
            if ((x + label.getWidth() + 5) > subScene.getWidth()) {
                x = subScene.getWidth() - (label.getWidth() + 5);
            }

            // is it above the view?
            if (y < 0) {
                y = 0;
            }

            // is it below the view
            if ((y + label.getHeight()) > subScene.getHeight()) {
                y = subScene.getHeight() - (label.getHeight() + 5);
            }

            //update the local transform of the label.
            label.getTransforms().setAll(new Translate(x, y));
        });
    }

    //////////////////////////////////

    @Override
    public void start(Stage primaryStage) throws Exception {
        Pane pane = createStarField();
        root.getChildren().add(pane);
        Scene scene = new Scene(root, sceneWidth, sceneHeight);
        primaryStage.setTitle("2D Labels over 3D SubScene");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }

}

最佳答案

正如 Kleopatra 所建议的,我在此处包含代码作为答案。
于是环顾四周,在FXyz库包中找到了类似的解决方案。我修改了它以适应我想要的东西,现在我有了我想要的工作版本。
我从 FXyz 中包含的唯一部分是 MathUtils 钳位静态方法。

import javafx.application.Application;
import javafx.application.Platform;
import javafx.geometry.Point3D;
import javafx.scene.*;
import javafx.scene.control.Label;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.Background;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.text.Font;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;

import java.util.HashMap;
import java.util.Random;

import static org.fxyz3d.geometry.MathUtils.clamp;

/**
 * example for flat labels
 */
public class StarFieldExample extends Application {

    final double sceneWidth = 600;
    final double sceneHeight = 600;

    private double mousePosX;
    private double mousePosY;
    private double mouseOldX;
    private double mouseOldY;
    private double mouseDeltaX;
    private double mouseDeltaY;

    private final Font font = new Font("arial", 10);

    // We'll use custom Rotate transforms to manage the coordinate conversions
    private final Rotate rotateX = new Rotate(0, Rotate.X_AXIS);
    private final Rotate rotateY = new Rotate(0, Rotate.Y_AXIS);
    private final Rotate rotateZ = new Rotate(0, Rotate.Z_AXIS);

    private final Group root = new Group();
    private final Group nodeGroup = new Group();  //all 3D nodes in scene
    private final Group labelGroup = new Group(); //all generic 3D labels

    //All shapes and labels linked via hash for easy update during camera movement
    private final HashMap<Shape3D, Label> shape3DToLabel = new HashMap<>();

    private SubScene subScene;

    private final Random random = new Random();

    private final static double RADIUS_MAX = 7;
    private final static double X_MAX = 300;
    private final static double Y_MAX = 300;
    private final static double Z_MAX = 300;

    public Pane createStarField() {

        //attach our custom rotation transforms so we can update the labels dynamically
        nodeGroup.getTransforms().addAll(rotateX, rotateY, rotateZ);

        subScene = new SubScene(nodeGroup, sceneWidth, sceneHeight, true, SceneAntialiasing.BALANCED);
        subScene.setFill(Color.BLACK);

        PerspectiveCamera camera = new PerspectiveCamera(true);
        camera.setNearClip(0.1);
        camera.setFarClip(10000.0);
        camera.setTranslateZ(-1000);

        subScene.setCamera(camera);
        Group sceneRoot = new Group(subScene);
        sceneRoot.getChildren().add(labelGroup);

        generateRandomStars(20);

        subScene.setOnMousePressed((MouseEvent me) -> {
                    mousePosX = me.getSceneX();
                    mousePosY = me.getSceneY();
                    mouseOldX = me.getSceneX();
                    mouseOldY = me.getSceneY();
                }
        );

        subScene.setOnMouseDragged((MouseEvent me) -> {
                    mouseOldX = mousePosX;
                    mouseOldY = mousePosY;
                    mousePosX = me.getSceneX();
                    mousePosY = me.getSceneY();
                    mouseDeltaX = (mousePosX - mouseOldX);
                    mouseDeltaY = (mousePosY - mouseOldY);
                    double modifier = 5.0;
                    double modifierFactor = 0.1;

                    if (me.isPrimaryButtonDown()) {
                        if (me.isAltDown()) { //roll
                            rotateZ.setAngle(((rotateZ.getAngle() + mouseDeltaX * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180); // +
                        } else {
                            rotateY.setAngle(((rotateY.getAngle() + mouseDeltaX * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180); // +
                            rotateX.setAngle(
                                    clamp(
                                            (((rotateX.getAngle() - mouseDeltaY * modifierFactor * modifier * 2.0) % 360 + 540) % 360 - 180),
                                            -60,
                                            60
                                    )
                            ); // -
                        }
                    }
                    updateLabels();
                }
        );

        // add to the 2D portion of this component
        Pane pane = new Pane();
        pane.setPrefSize(sceneWidth, sceneHeight);
        pane.setMaxSize(Pane.USE_COMPUTED_SIZE, Pane.USE_COMPUTED_SIZE);
        pane.setMinSize(Pane.USE_COMPUTED_SIZE, Pane.USE_COMPUTED_SIZE);
        pane.setBackground(Background.EMPTY);
        pane.getChildren().add(sceneRoot);
        pane.setPickOnBounds(false);

        subScene.widthProperty().bind(pane.widthProperty());
        subScene.heightProperty().bind(pane.heightProperty());
        Platform.runLater(this::updateLabels);
        return (pane);
    }

    public void generateRandomStars(int numberStars) {
        for (int i = 0; i < numberStars; i++) {
            double radius = random.nextDouble() * RADIUS_MAX;
            Color color = randomColor();
            double x = random.nextDouble() * X_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);
            double y = random.nextDouble() * Y_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);
            double z = random.nextDouble() * Z_MAX * 2 / 3 * (random.nextBoolean() ? 1 : -1);

            String labelText = "Star " + i;
            boolean fadeFlag = random.nextBoolean();
            createSphereLabel(radius, x, y, z, color, labelText);
        }
    }

    private Color randomColor() {
        int r = random.nextInt(255);
        int g = random.nextInt(255);
        int b = random.nextInt(255);
        return Color.rgb(r, g, b);
    }


    private void createSphereLabel(double radius, double x, double y, double z, Color color, String labelText) {
        Sphere sphere = new Sphere(radius);
        sphere.setTranslateX(x);
        sphere.setTranslateY(y);
        sphere.setTranslateZ(z);
        sphere.setMaterial(new PhongMaterial(color));
        //add our nodes to the group that will later be added to the 3D scene
        nodeGroup.getChildren().add(sphere);

        Label label = new Label(labelText);
        label.setTextFill(color);
        label.setFont(font);
        labelGroup.getChildren().add(label);

        //Add to hashmap so updateLabels() can manage the label position
        shape3DToLabel.put(sphere, label);
    }

    private void updateLabels() {
        shape3DToLabel.forEach((node, label) -> {
            Point3D coordinates = node.localToScene(Point3D.ZERO, true);

            //Clipping Logic
            //if coordinates are outside of the scene it could
            //stretch the screen so don't transform them
            double x = coordinates.getX();
            double y = coordinates.getY();

            // is it left of the view?
            if (x < 0) {
                x = 0;
            }

            // is it right of the view?
            if ((x + label.getWidth() + 5) > subScene.getWidth()) {
                x = subScene.getWidth() - (label.getWidth() + 5);
            }

            // is it above the view?
            if (y < 0) {
                y = 0;
            }

            // is it below the view
            if ((y + label.getHeight()) > subScene.getHeight()) {
                y = subScene.getHeight() - (label.getHeight() + 5);
            }

            //update the local transform of the label.
            label.getTransforms().setAll(new Translate(x, y));
        });
    }

    //////////////////////////////////

    @Override
    public void start(Stage primaryStage) throws Exception {
        Pane pane = createStarField();
        root.getChildren().add(pane);
        Scene scene = new Scene(root, sceneWidth, sceneHeight);
        primaryStage.setTitle("2D Labels over 3D SubScene");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }

}

关于java - 对于 3d 星场(在 JavaFX 中),使标签与查看者的视角保持一致,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/64265755/

相关文章:

JavaFX widthProperty 不刷新

JavaFX 11 : IllegalAccessError when creating Label

Eclipse 4.9 上的 Java 11 和 E(fx)clipse JavaFX 插件 : An error has occurred - see the log file

java - ImageMagick 命令不适用于 OSX 中的 JAVA 代码

java - 具有Parsley框架的GraniteDS

java - TableView 中 RadioButton 的奇怪行为

java - 发生此错误时 Error :(1, 1) java.desktop 和 java.datatransfer 中的 java : module JavaFX reads package java. awt

java - 为什么即使网址正常,此代码也为什么会引发java.io.FileNotFoundException

java - jar 不使用包含的类或命名空间冲突

java - 将项目资源中的图像写入字节数组