旋转后如何正确获取3D形状的屏幕坐标
How to correctly obtain screen coordinates of 3D shape after rotation
我需要能够通过绘制一个矩形区域在我的 3d 模型中 select 一些形状，并且位于该区域中的所有形状都是 selected。
如果只有 x 或 y 旋转，我可以绘制区域和 select 节点。但是 x 和 y 的大多数组合给出了不正确的结果。
我认为获取屏幕坐标中的鼠标和节点位置并进行比较会是一件简单的事情，但这并没有按预期工作。
在下面的应用程序中，您可以使用鼠标右键绘制一个区域（您必须单击一个球体才能开始，我不确定为什么，它们在子场景上的鼠标事件只有在您单击时才会触发在球体上？）。再次右键单击（再次在球体上）清除 selection。
您可以左键单击拖动来旋转模型（同样您必须从球体开始）。围绕 x 轴旋转任意数量后，您可以成功 select 一个区域。同样绕 y 轴旋转。然而，x 和 y 旋转的组合给出了错误的结果。例如沿对角线拖动节点，结果如下图
Result of selection after x and y rotation
有什么问题吗？或建议其他方法来解决这个问题？提前致谢
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Random;
import javafx.application.Application;
import javafx.geometry.Point2D;
import javafx.scene.DepthTest;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.SceneAntialiasing;
import javafx.scene.SubScene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.Slider;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.paint.Material;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Rectangle;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Transform;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;
public class ScreenSelection extends Application {
private final PerspectiveCamera camera = new PerspectiveCamera(true);
private final Group root = new Group();
private final Group world = new Group();
private final XFormWorld camPiv = new XFormWorld();
private final Slider zoom = new Slider(-100, 0, -50);
private final Button reset = new Button("Reset");
private final Pane pane = new Pane();
private final BorderPane main = new BorderPane();
double mousePosX, mousePosY, mouseOldX, mouseOldY, mouseDeltaX, mouseDeltaY;
double mouseFactorX, mouseFactorY;
public void start(Stage stage) throws Exception {
camera.setTranslateZ(zoom.getValue());
reset.setOnAction(eh -> {
camPiv.reset();
zoom.setValue(-50);
});
camera.setFieldOfView(60);
camPiv.getChildren().add(camera);
Collection<Shape3D> world = createWorld();
RectangleSelect rs = new RectangleSelect(main, world);
this.world.getChildren().addAll(world);
root.getChildren().addAll(camPiv, this.world);
SubScene subScene = new SubScene(root, -1, -1, true, SceneAntialiasing.BALANCED);
subScene.setDepthTest(DepthTest.ENABLE);
subScene.setCamera(camera);
subScene.heightProperty().bind(pane.heightProperty());
subScene.widthProperty().bind(pane.widthProperty());
zoom.valueProperty().addListener((o, oldA, newA) -> camera.setTranslateZ(newA.doubleValue()));
HBox controls = new HBox();
controls.getChildren().addAll(new HBox(new Label("Zoom: "), zoom), new HBox(reset));
pane.getChildren().addAll(controls, subScene);
MenuBar menu = new MenuBar(new Menu("File"));
main.setTop(menu);
main.setCenter(pane);
Scene scene = new Scene(main);
subScene.setOnMousePressed((MouseEvent me) -> {
mousePosX = me.getSceneX();
mousePosY = me.getSceneY();
});
subScene.setOnMouseDragged((MouseEvent me) -> {
if (me.isSecondaryButtonDown()) {
rs.onMouseDragged(me);
} else if (me.isPrimaryButtonDown()) {
mouseOldX = mousePosX;
mouseOldY = mousePosY;
mousePosX = me.getSceneX();
mousePosY = me.getSceneY();
mouseDeltaX = (mousePosX - mouseOldX);
mouseDeltaY = (mousePosY - mouseOldY);
camPiv.ry(mouseDeltaX * 180.0 / subScene.getWidth());
camPiv.rx(-mouseDeltaY * 180.0 / subScene.getHeight());
}
});
subScene.setOnMouseReleased((MouseEvent me) -> {
rs.omMouseDragReleased(me);
});
subScene.setOnMouseClicked((MouseEvent me) -> {
if (me.getButton() == MouseButton.SECONDARY) {
rs.clearSelection();
}
});
stage.setScene(scene);
stage.setWidth(800);
stage.setHeight(800);
stage.show();
}
private Collection<Shape3D> createWorld() {
List<Shape3D> shapes = new ArrayList<Shape3D>();
Random random = new Random(System.currentTimeMillis());
for (int i=0; i<4000; i++) {
double x = (random.nextDouble() - 0.5) * 30;
double y = (random.nextDouble() - 0.5) * 30 ;
double z = (random.nextDouble() - 0.5) * 30 ;
Sphere point = new Sphere(0.2);
point.setMaterial(new PhongMaterial(Color.SKYBLUE));
point.setPickOnBounds(false);
point.getTransforms().add(new Translate(x, y, z));
shapes.add(point);
}
return shapes;
}
public static void main(String[] args) {
launch(args);
}
public class XFormWorld extends Group {
Transform rotation = new Rotate();
Translate translate = new Translate();
public XFormWorld() {
getTransforms().addAll(rotation, translate);
}
public void reset() {
rotation = new Rotate();
getTransforms().set(0, rotation);
}
public void rx(double angle) {
rotation = rotation.createConcatenation(new Rotate(angle, Rotate.X_AXIS));
getTransforms().set(0, rotation);
}
public void ry(double angle) {
rotation = rotation.createConcatenation(new Rotate(angle, Rotate.Y_AXIS));
getTransforms().set(0, rotation);
}
public void tx(double amount) {
translate.setX(translate.getX() + amount);
}
}
public class RectangleSelect {
private static final int START_X = 0;
private static final int START_Y = 1;
private static final int END_X = 2;
private static final int END_Y = 3;
private double[] sceneCoords = new double[2]; //mouse drag x, y in scene coords
private double[] screenCoords = new double[2]; //mouse drag current x, y in screen coords
private double[] boundsInScreenCoords = new double[4]; //top left x, y, bottom right x,y in screen coords
private Collection<Shape3D> world;
private PhongMaterial selected = new PhongMaterial(Color.YELLOW);
private Rectangle rectangle;
public RectangleSelect(Pane pane, Collection<Shape3D> world) {
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
rectangle = new Rectangle();
rectangle.setStroke(Color.RED);
rectangle.setOpacity(0.0);
rectangle.setMouseTransparent(true);
rectangle.setFill(null);
this.world = world;
pane.getChildren().add(rectangle);
}
public void onMouseDragged(MouseEvent me) {
clearSelection();
if (sceneCoords[START_X] == Double.MIN_VALUE) {
sceneCoords[START_X] = me.getSceneX();
sceneCoords[START_Y] = me.getSceneY();
screenCoords[START_X] = me.getScreenX();
screenCoords[START_Y] = me.getScreenY();
}
double sceneX = me.getSceneX();
double sceneY = me.getSceneY();
double screenX = me.getScreenX();
double screenY = me.getScreenY();
double topX = Math.min(sceneCoords[START_X], sceneX);
double bottomX = Math.max(sceneCoords[START_X], sceneX);
double leftY = Math.min(sceneCoords[START_Y], sceneY);
double rightY = Math.max(sceneCoords[START_Y], sceneY);
boundsInScreenCoords[START_X] = Math.min(screenCoords[START_X], screenX);
boundsInScreenCoords[END_X]= Math.max(screenCoords[START_X], screenX);
boundsInScreenCoords[START_Y] = Math.min(screenCoords[START_Y], screenY);
boundsInScreenCoords[END_Y] = Math.max(screenCoords[START_Y], screenY);
world.forEach(this::selectIfInBounds);
rectangle.setX(topX);
rectangle.setY(leftY);
rectangle.setWidth(bottomX - topX);
rectangle.setHeight(rightY - leftY);
rectangle.setOpacity(1.0);
}
private void selectIfInBounds(Shape3D node) {
Point2D screenCoods = node.localToScreen(0.0, 0.0, 0.0);
if (screenCoods.getX() > boundsInScreenCoords[START_X] &&
screenCoods.getY() > boundsInScreenCoords[START_Y] &&
screenCoods.getX() < boundsInScreenCoords[END_X] &&
screenCoods.getY() < boundsInScreenCoords[END_Y]) {
Material m = node.getMaterial();
node.getProperties().put("material", m);
node.setMaterial(selected);
}
}
private void unselect(Shape3D node) {
Material m = (Material) node.getProperties().get("material");
if (m != null) {
node.setMaterial(m);
}
}
public void omMouseDragReleased(MouseEvent me) {
rectangle.setOpacity(0.0);
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
}
public void clearSelection() {
world.forEach(this::unselect);
}
}
}
感谢 user1803551 提供这些链接，第一个是一个很好的跟踪错误的用例，它确实是 GeneralTransform3D.transform(Vec3d)
中的错误
GeneralTransform3D.transform(Vec3d)的实现（在计算鼠标位置的过程中被Camera.project调用）调用了同一个点对象的两个arg变换方法。即
public Vec3d transform(Vec3d point) {
return transform(point, point);
}
用同一个对象调用它，计算很麻烦。您可能会看到，如果 pointOut 和 point 是同一个对象，那么 pointOut.y 的计算将不正确（这是来自 GeneralTransform3D.transform）
pointOut.x = (float) (mat[0] * point.x + mat[1] * point.y
+ mat[2] * point.z + mat[3]);
pointOut.y = (float) (mat[4] * point.x + mat[5] * point.y
+ mat[6] * point.z + mat[7]);
一切都很好，但不确定如何解决它
我确认这是 comments 中列出的错误。对于您的情况，我认为最简单的解决方案是旋转 world 而不是相机。由于这些是仅有的 2 个相对移动的对象，因此移动哪一个并不重要。如果你想统一变换，你也可以将缩放应用到世界而不是相机，但这并不重要。
旋转世界
通过将世界设置为 XFormWorld 使世界可旋转，并完全删除 camPiv。请注意，没有理由将 camPiv 添加到场景中，因为它是一个空组；相机只能通过 setCamera 添加，然后您可以绑定它的变换（见下文）。
您需要通过两种方式更改数学：
- 翻转
rx 和 ry 的旋转值，因为在 +x 中旋转世界就像在 -x 中旋转相机（与 y 相同).
- 更正旋转轴。如果在
x 轴上旋转，然后在 y 轴上旋转，y 轴旋转实际上会围绕 z 旋转（因为旋转矩阵规则）。这意味着新旋转的枢轴取决于当前旋转。如果您在 x 上旋转，您现在需要在 z 上旋转才能获得 y 旋转。数学很简单，但你需要知道你在做什么。
直接改造相机
即使在变换相机时也不需要 camPiv 的原因是因为您可以直接绑定到它的变换。在你的情况下，你可以做
camera.translateZProperty().bind(zoom.valueProperty());
而不是烦人的组合
camera.setTranslateZ(zoom.getValue());
zoom.valueProperty().addListener((o, oldA, newA) -> camera.setTranslateZ(newA.doubleValue()));
对于任何 Transform，将其添加到 camera.getTransforms() 并将其值（角度、平移...）绑定到 DoublePropertys，其值是您通过输入。
鼠标事件和边界拾取
您的 subScene（和 world）包含许多节点，它们之间有空 space。默认情况下，当您点击 subScene 时，只有当您点击其中的一个（非鼠标透明）节点时，事件才会传递给它。这是因为 pickOnBounds 是 false，这意味着单击 "passes through" 直到它击中某个东西。如果你加上
subScene.setPickOnBounds(true);
容器 (subScene) 将接收其框边界内的任何事件，无论那里是否有节点。
修复后会遇到新的问题：绘制矩形后松开鼠标会导致矩形消失clearSelection()。这是因为你在 onMouseClicked 中调用了那个方法，但是在拖动结束时生成了一个点击事件，因为有一个按下和一个释放。如果是单击 而不拖动 ，您想要的是清除选择。这是通过 isStillSincePress():
完成的
subScene.setOnMouseClicked(me -> {
if (me.getButton() == MouseButton.SECONDARY && me.isStillSincePress()) {
rs.clearSelection();
}
});
你没有遇到这种情况的原因是 subScene 如果发生在空的 space 上则没有收到释放事件。总结：
- 按下空按钮 space：事件未注册 - 什么都没发生。
- 按下球体：事件注册 - 三角形绘制开始。
- 释放为空 space：事件未注册 - 矩形未清除。
- 在球体上发布：事件已注册 - 矩形已清除。
布局
除非您需要绝对定位（而且您很少这样做），否则不要使用 Pane。选择一个能更好地完成工作的子类。 StackPane 允许您通过使用图层将控件放在 SubScene 之上。设置 setPickOnBounds 为 false 允许下层正常接收事件。此外，我使用 AnchorPane 将控件放在左上角。
工作解决方案
这是您修改后的代码。我在处理它的时候做了一些重构，这样我就可以更容易地使用它。我相信整个 RectangleSelect 也可以进行大量修改，但问题已经足够加载了。
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Random;
import javafx.application.Application;
import javafx.geometry.Point2D;
import javafx.geometry.Point3D;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.SceneAntialiasing;
import javafx.scene.SubScene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.Slider;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.paint.Material;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Rectangle;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Transform;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;
public class ScreenSelectionNew extends Application {
private final PerspectiveCamera camera = new PerspectiveCamera(true);
private final XFormWorld world = new XFormWorld();
private double mousePosX, mousePosY, mouseOldX, mouseOldY;
@Override
public void start(Stage stage) throws Exception {
BorderPane main = new BorderPane();
StackPane stackPane = new StackPane();
SubScene subScene = setupSubScene(main);
subScene.heightProperty().bind(stackPane.heightProperty());
subScene.widthProperty().bind(stackPane.widthProperty());
stackPane.getChildren().addAll(subScene, setupControls());
MenuBar menu = new MenuBar(new Menu("File"));
main.setTop(menu);
main.setCenter(stackPane);
Scene scene = new Scene(main);
stage.setScene(scene);
stage.setWidth(800);
stage.setHeight(800);
stage.show();
}
private SubScene setupSubScene(Pane parent) {
Collection<Shape3D> worldContent = createWorld();
world.getChildren().addAll(worldContent);
SubScene subScene = new SubScene(world, -1, -1, true, SceneAntialiasing.BALANCED);
subScene.setCamera(camera);
subScene.setPickOnBounds(true);
camera.setFieldOfView(60);
RectangleSelect rs = new RectangleSelect(parent, worldContent);
subScene.setOnMousePressed(me -> {
mousePosX = me.getX();
mousePosY = me.getY();
});
subScene.setOnMouseDragged(me -> {
if (me.isSecondaryButtonDown()) {
rs.onMouseDragged(me);
} else if (me.isPrimaryButtonDown()) {
mouseOldX = mousePosX;
mouseOldY = mousePosY;
mousePosX = me.getX();
mousePosY = me.getY();
double mouseDeltaX = (mousePosX - mouseOldX);
double mouseDeltaY = (mousePosY - mouseOldY);
world.rx(mouseDeltaY * 180.0 / subScene.getHeight());
world.ry(-mouseDeltaX * 180.0 / subScene.getWidth());
}
});
subScene.setOnMouseReleased(me -> rs.onMouseDragReleased(me));
subScene.setOnMouseClicked(me -> {
if (me.getButton() == MouseButton.SECONDARY && me.isStillSincePress()) {
rs.clearSelection();
}
});
return subScene;
}
private Pane setupControls() {
Slider zoom = new Slider(-100, 0, -50);
camera.translateZProperty().bind(zoom.valueProperty());
Button reset = new Button("Reset");
reset.setOnAction(eh -> {
world.reset();
zoom.setValue(-50);
});
HBox controls = new HBox(new Label("Zoom: "), zoom, reset);
AnchorPane anchorPane = new AnchorPane(controls);
anchorPane.setPickOnBounds(false);
return anchorPane;
}
private Collection<Shape3D> createWorld() {
List<Shape3D> shapes = new ArrayList<>();
Random random = new Random(System.currentTimeMillis());
for (int i = 0; i < 4000; i++) {
double x = (random.nextDouble() - 0.5) * 30;
double y = (random.nextDouble() - 0.5) * 30;
double z = (random.nextDouble() - 0.5) * 30;
Sphere point = new Sphere(0.2);
point.setMaterial(new PhongMaterial(Color.SKYBLUE));
point.getTransforms().add(new Translate(x, y, z));
shapes.add(point);
}
return shapes;
}
public static void main(String[] args) {
launch(args);
}
public class XFormWorld extends Group {
Transform rotation = new Rotate();
public XFormWorld() {
getTransforms().addAll(rotation);
}
public void reset() {
rotation = new Rotate();
getTransforms().set(0, rotation);
}
public void rx(double angle) {
Point3D axis = new Point3D(rotation.getMxx(), rotation.getMxy(), rotation.getMxz());
rotation = rotation.createConcatenation(new Rotate(angle, axis));
getTransforms().set(0, rotation);
}
public void ry(double angle) {
Point3D axis = new Point3D(rotation.getMyx(), rotation.getMyy(), rotation.getMyz());
rotation = rotation.createConcatenation(new Rotate(angle, axis));
getTransforms().set(0, rotation);
}
}
public class RectangleSelect {
private static final int START_X = 0;
private static final int START_Y = 1;
private static final int END_X = 2;
private static final int END_Y = 3;
private double[] sceneCoords = new double[2]; //mouse drag x, y in scene coords
private double[] screenCoords = new double[2]; //mouse drag current x, y in screen coords
private double[] boundsInScreenCoords = new double[4]; //top left x, y, bottom right x,y in screen coords
private Collection<Shape3D> world;
private PhongMaterial selected = new PhongMaterial(Color.YELLOW);
private Rectangle rectangle;
public RectangleSelect(Pane pane, Collection<Shape3D> world) {
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
rectangle = new Rectangle();
rectangle.setStroke(Color.RED);
rectangle.setOpacity(0.0);
rectangle.setMouseTransparent(true);
rectangle.setFill(null);
this.world = world;
pane.getChildren().add(rectangle);
}
public void onMouseDragged(MouseEvent me) {
clearSelection();
if (sceneCoords[START_X] == Double.MIN_VALUE) {
sceneCoords[START_X] = me.getSceneX();
sceneCoords[START_Y] = me.getSceneY();
screenCoords[START_X] = me.getScreenX();
screenCoords[START_Y] = me.getScreenY();
}
double sceneX = me.getSceneX();
double sceneY = me.getSceneY();
double screenX = me.getScreenX();
double screenY = me.getScreenY();
double topX = Math.min(sceneCoords[START_X], sceneX);
double bottomX = Math.max(sceneCoords[START_X], sceneX);
double leftY = Math.min(sceneCoords[START_Y], sceneY);
double rightY = Math.max(sceneCoords[START_Y], sceneY);
boundsInScreenCoords[START_X] = Math.min(screenCoords[START_X], screenX);
boundsInScreenCoords[END_X] = Math.max(screenCoords[START_X], screenX);
boundsInScreenCoords[START_Y] = Math.min(screenCoords[START_Y], screenY);
boundsInScreenCoords[END_Y] = Math.max(screenCoords[START_Y], screenY);
world.forEach(this::selectIfInBounds);
rectangle.setX(topX);
rectangle.setY(leftY);
rectangle.setWidth(bottomX - topX);
rectangle.setHeight(rightY - leftY);
rectangle.setOpacity(1.0);
}
private void selectIfInBounds(Shape3D node) {
Point2D screenCoods = node.localToScreen(0.0, 0.0, 0.0);
if (screenCoods.getX() > boundsInScreenCoords[START_X] &&
screenCoods.getY() > boundsInScreenCoords[START_Y] &&
screenCoods.getX() < boundsInScreenCoords[END_X] &&
screenCoods.getY() < boundsInScreenCoords[END_Y]) {
Material m = node.getMaterial();
node.getProperties().put("material", m);
node.setMaterial(selected);
}
}
private void unselect(Shape3D node) {
Material m = (Material) node.getProperties().get("material");
if (m != null) {
node.setMaterial(m);
}
}
public void onMouseDragReleased(MouseEvent me) {
rectangle.setOpacity(0.0);
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
}
public void clearSelection() {
world.forEach(this::unselect);
}
}
}
我需要能够通过绘制一个矩形区域在我的 3d 模型中 select 一些形状，并且位于该区域中的所有形状都是 selected。
如果只有 x 或 y 旋转，我可以绘制区域和 select 节点。但是 x 和 y 的大多数组合给出了不正确的结果。
我认为获取屏幕坐标中的鼠标和节点位置并进行比较会是一件简单的事情，但这并没有按预期工作。
在下面的应用程序中，您可以使用鼠标右键绘制一个区域（您必须单击一个球体才能开始，我不确定为什么，它们在子场景上的鼠标事件只有在您单击时才会触发在球体上？）。再次右键单击（再次在球体上）清除 selection。
您可以左键单击拖动来旋转模型（同样您必须从球体开始）。围绕 x 轴旋转任意数量后，您可以成功 select 一个区域。同样绕 y 轴旋转。然而，x 和 y 旋转的组合给出了错误的结果。例如沿对角线拖动节点，结果如下图
Result of selection after x and y rotation
有什么问题吗？或建议其他方法来解决这个问题？提前致谢
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Random;
import javafx.application.Application;
import javafx.geometry.Point2D;
import javafx.scene.DepthTest;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.SceneAntialiasing;
import javafx.scene.SubScene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.Slider;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.paint.Material;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Rectangle;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Transform;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;
public class ScreenSelection extends Application {
private final PerspectiveCamera camera = new PerspectiveCamera(true);
private final Group root = new Group();
private final Group world = new Group();
private final XFormWorld camPiv = new XFormWorld();
private final Slider zoom = new Slider(-100, 0, -50);
private final Button reset = new Button("Reset");
private final Pane pane = new Pane();
private final BorderPane main = new BorderPane();
double mousePosX, mousePosY, mouseOldX, mouseOldY, mouseDeltaX, mouseDeltaY;
double mouseFactorX, mouseFactorY;
public void start(Stage stage) throws Exception {
camera.setTranslateZ(zoom.getValue());
reset.setOnAction(eh -> {
camPiv.reset();
zoom.setValue(-50);
});
camera.setFieldOfView(60);
camPiv.getChildren().add(camera);
Collection<Shape3D> world = createWorld();
RectangleSelect rs = new RectangleSelect(main, world);
this.world.getChildren().addAll(world);
root.getChildren().addAll(camPiv, this.world);
SubScene subScene = new SubScene(root, -1, -1, true, SceneAntialiasing.BALANCED);
subScene.setDepthTest(DepthTest.ENABLE);
subScene.setCamera(camera);
subScene.heightProperty().bind(pane.heightProperty());
subScene.widthProperty().bind(pane.widthProperty());
zoom.valueProperty().addListener((o, oldA, newA) -> camera.setTranslateZ(newA.doubleValue()));
HBox controls = new HBox();
controls.getChildren().addAll(new HBox(new Label("Zoom: "), zoom), new HBox(reset));
pane.getChildren().addAll(controls, subScene);
MenuBar menu = new MenuBar(new Menu("File"));
main.setTop(menu);
main.setCenter(pane);
Scene scene = new Scene(main);
subScene.setOnMousePressed((MouseEvent me) -> {
mousePosX = me.getSceneX();
mousePosY = me.getSceneY();
});
subScene.setOnMouseDragged((MouseEvent me) -> {
if (me.isSecondaryButtonDown()) {
rs.onMouseDragged(me);
} else if (me.isPrimaryButtonDown()) {
mouseOldX = mousePosX;
mouseOldY = mousePosY;
mousePosX = me.getSceneX();
mousePosY = me.getSceneY();
mouseDeltaX = (mousePosX - mouseOldX);
mouseDeltaY = (mousePosY - mouseOldY);
camPiv.ry(mouseDeltaX * 180.0 / subScene.getWidth());
camPiv.rx(-mouseDeltaY * 180.0 / subScene.getHeight());
}
});
subScene.setOnMouseReleased((MouseEvent me) -> {
rs.omMouseDragReleased(me);
});
subScene.setOnMouseClicked((MouseEvent me) -> {
if (me.getButton() == MouseButton.SECONDARY) {
rs.clearSelection();
}
});
stage.setScene(scene);
stage.setWidth(800);
stage.setHeight(800);
stage.show();
}
private Collection<Shape3D> createWorld() {
List<Shape3D> shapes = new ArrayList<Shape3D>();
Random random = new Random(System.currentTimeMillis());
for (int i=0; i<4000; i++) {
double x = (random.nextDouble() - 0.5) * 30;
double y = (random.nextDouble() - 0.5) * 30 ;
double z = (random.nextDouble() - 0.5) * 30 ;
Sphere point = new Sphere(0.2);
point.setMaterial(new PhongMaterial(Color.SKYBLUE));
point.setPickOnBounds(false);
point.getTransforms().add(new Translate(x, y, z));
shapes.add(point);
}
return shapes;
}
public static void main(String[] args) {
launch(args);
}
public class XFormWorld extends Group {
Transform rotation = new Rotate();
Translate translate = new Translate();
public XFormWorld() {
getTransforms().addAll(rotation, translate);
}
public void reset() {
rotation = new Rotate();
getTransforms().set(0, rotation);
}
public void rx(double angle) {
rotation = rotation.createConcatenation(new Rotate(angle, Rotate.X_AXIS));
getTransforms().set(0, rotation);
}
public void ry(double angle) {
rotation = rotation.createConcatenation(new Rotate(angle, Rotate.Y_AXIS));
getTransforms().set(0, rotation);
}
public void tx(double amount) {
translate.setX(translate.getX() + amount);
}
}
public class RectangleSelect {
private static final int START_X = 0;
private static final int START_Y = 1;
private static final int END_X = 2;
private static final int END_Y = 3;
private double[] sceneCoords = new double[2]; //mouse drag x, y in scene coords
private double[] screenCoords = new double[2]; //mouse drag current x, y in screen coords
private double[] boundsInScreenCoords = new double[4]; //top left x, y, bottom right x,y in screen coords
private Collection<Shape3D> world;
private PhongMaterial selected = new PhongMaterial(Color.YELLOW);
private Rectangle rectangle;
public RectangleSelect(Pane pane, Collection<Shape3D> world) {
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
rectangle = new Rectangle();
rectangle.setStroke(Color.RED);
rectangle.setOpacity(0.0);
rectangle.setMouseTransparent(true);
rectangle.setFill(null);
this.world = world;
pane.getChildren().add(rectangle);
}
public void onMouseDragged(MouseEvent me) {
clearSelection();
if (sceneCoords[START_X] == Double.MIN_VALUE) {
sceneCoords[START_X] = me.getSceneX();
sceneCoords[START_Y] = me.getSceneY();
screenCoords[START_X] = me.getScreenX();
screenCoords[START_Y] = me.getScreenY();
}
double sceneX = me.getSceneX();
double sceneY = me.getSceneY();
double screenX = me.getScreenX();
double screenY = me.getScreenY();
double topX = Math.min(sceneCoords[START_X], sceneX);
double bottomX = Math.max(sceneCoords[START_X], sceneX);
double leftY = Math.min(sceneCoords[START_Y], sceneY);
double rightY = Math.max(sceneCoords[START_Y], sceneY);
boundsInScreenCoords[START_X] = Math.min(screenCoords[START_X], screenX);
boundsInScreenCoords[END_X]= Math.max(screenCoords[START_X], screenX);
boundsInScreenCoords[START_Y] = Math.min(screenCoords[START_Y], screenY);
boundsInScreenCoords[END_Y] = Math.max(screenCoords[START_Y], screenY);
world.forEach(this::selectIfInBounds);
rectangle.setX(topX);
rectangle.setY(leftY);
rectangle.setWidth(bottomX - topX);
rectangle.setHeight(rightY - leftY);
rectangle.setOpacity(1.0);
}
private void selectIfInBounds(Shape3D node) {
Point2D screenCoods = node.localToScreen(0.0, 0.0, 0.0);
if (screenCoods.getX() > boundsInScreenCoords[START_X] &&
screenCoods.getY() > boundsInScreenCoords[START_Y] &&
screenCoods.getX() < boundsInScreenCoords[END_X] &&
screenCoods.getY() < boundsInScreenCoords[END_Y]) {
Material m = node.getMaterial();
node.getProperties().put("material", m);
node.setMaterial(selected);
}
}
private void unselect(Shape3D node) {
Material m = (Material) node.getProperties().get("material");
if (m != null) {
node.setMaterial(m);
}
}
public void omMouseDragReleased(MouseEvent me) {
rectangle.setOpacity(0.0);
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
}
public void clearSelection() {
world.forEach(this::unselect);
}
}
}
感谢 user1803551 提供这些链接，第一个是一个很好的跟踪错误的用例，它确实是 GeneralTransform3D.transform(Vec3d)
中的错误GeneralTransform3D.transform(Vec3d)的实现（在计算鼠标位置的过程中被Camera.project调用）调用了同一个点对象的两个arg变换方法。即
public Vec3d transform(Vec3d point) {
return transform(point, point);
}
用同一个对象调用它，计算很麻烦。您可能会看到，如果 pointOut 和 point 是同一个对象，那么 pointOut.y 的计算将不正确（这是来自 GeneralTransform3D.transform）
pointOut.x = (float) (mat[0] * point.x + mat[1] * point.y
+ mat[2] * point.z + mat[3]);
pointOut.y = (float) (mat[4] * point.x + mat[5] * point.y
+ mat[6] * point.z + mat[7]);
一切都很好，但不确定如何解决它
我确认这是 comments 中列出的错误。对于您的情况，我认为最简单的解决方案是旋转 world 而不是相机。由于这些是仅有的 2 个相对移动的对象，因此移动哪一个并不重要。如果你想统一变换，你也可以将缩放应用到世界而不是相机，但这并不重要。
旋转世界
通过将世界设置为 XFormWorld 使世界可旋转，并完全删除 camPiv。请注意，没有理由将 camPiv 添加到场景中，因为它是一个空组；相机只能通过 setCamera 添加，然后您可以绑定它的变换（见下文）。
您需要通过两种方式更改数学：
- 翻转
rx和ry的旋转值，因为在+x中旋转世界就像在-x中旋转相机（与y相同). - 更正旋转轴。如果在
x轴上旋转，然后在y轴上旋转，y轴旋转实际上会围绕z旋转（因为旋转矩阵规则）。这意味着新旋转的枢轴取决于当前旋转。如果您在x上旋转，您现在需要在z上旋转才能获得y旋转。数学很简单，但你需要知道你在做什么。
直接改造相机
即使在变换相机时也不需要 camPiv 的原因是因为您可以直接绑定到它的变换。在你的情况下，你可以做
camera.translateZProperty().bind(zoom.valueProperty());
而不是烦人的组合
camera.setTranslateZ(zoom.getValue());
zoom.valueProperty().addListener((o, oldA, newA) -> camera.setTranslateZ(newA.doubleValue()));
对于任何 Transform，将其添加到 camera.getTransforms() 并将其值（角度、平移...）绑定到 DoublePropertys，其值是您通过输入。
鼠标事件和边界拾取
您的 subScene（和 world）包含许多节点，它们之间有空 space。默认情况下，当您点击 subScene 时，只有当您点击其中的一个（非鼠标透明）节点时，事件才会传递给它。这是因为 pickOnBounds 是 false，这意味着单击 "passes through" 直到它击中某个东西。如果你加上
subScene.setPickOnBounds(true);
容器 (subScene) 将接收其框边界内的任何事件，无论那里是否有节点。
修复后会遇到新的问题：绘制矩形后松开鼠标会导致矩形消失clearSelection()。这是因为你在 onMouseClicked 中调用了那个方法，但是在拖动结束时生成了一个点击事件，因为有一个按下和一个释放。如果是单击 而不拖动 ，您想要的是清除选择。这是通过 isStillSincePress():
subScene.setOnMouseClicked(me -> {
if (me.getButton() == MouseButton.SECONDARY && me.isStillSincePress()) {
rs.clearSelection();
}
});
你没有遇到这种情况的原因是 subScene 如果发生在空的 space 上则没有收到释放事件。总结：
- 按下空按钮 space：事件未注册 - 什么都没发生。
- 按下球体：事件注册 - 三角形绘制开始。
- 释放为空 space：事件未注册 - 矩形未清除。
- 在球体上发布：事件已注册 - 矩形已清除。
布局
除非您需要绝对定位（而且您很少这样做），否则不要使用 Pane。选择一个能更好地完成工作的子类。 StackPane 允许您通过使用图层将控件放在 SubScene 之上。设置 setPickOnBounds 为 false 允许下层正常接收事件。此外，我使用 AnchorPane 将控件放在左上角。
工作解决方案
这是您修改后的代码。我在处理它的时候做了一些重构，这样我就可以更容易地使用它。我相信整个 RectangleSelect 也可以进行大量修改，但问题已经足够加载了。
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Random;
import javafx.application.Application;
import javafx.geometry.Point2D;
import javafx.geometry.Point3D;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.SceneAntialiasing;
import javafx.scene.SubScene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.Slider;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.paint.Material;
import javafx.scene.paint.PhongMaterial;
import javafx.scene.shape.Rectangle;
import javafx.scene.shape.Shape3D;
import javafx.scene.shape.Sphere;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Transform;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;
public class ScreenSelectionNew extends Application {
private final PerspectiveCamera camera = new PerspectiveCamera(true);
private final XFormWorld world = new XFormWorld();
private double mousePosX, mousePosY, mouseOldX, mouseOldY;
@Override
public void start(Stage stage) throws Exception {
BorderPane main = new BorderPane();
StackPane stackPane = new StackPane();
SubScene subScene = setupSubScene(main);
subScene.heightProperty().bind(stackPane.heightProperty());
subScene.widthProperty().bind(stackPane.widthProperty());
stackPane.getChildren().addAll(subScene, setupControls());
MenuBar menu = new MenuBar(new Menu("File"));
main.setTop(menu);
main.setCenter(stackPane);
Scene scene = new Scene(main);
stage.setScene(scene);
stage.setWidth(800);
stage.setHeight(800);
stage.show();
}
private SubScene setupSubScene(Pane parent) {
Collection<Shape3D> worldContent = createWorld();
world.getChildren().addAll(worldContent);
SubScene subScene = new SubScene(world, -1, -1, true, SceneAntialiasing.BALANCED);
subScene.setCamera(camera);
subScene.setPickOnBounds(true);
camera.setFieldOfView(60);
RectangleSelect rs = new RectangleSelect(parent, worldContent);
subScene.setOnMousePressed(me -> {
mousePosX = me.getX();
mousePosY = me.getY();
});
subScene.setOnMouseDragged(me -> {
if (me.isSecondaryButtonDown()) {
rs.onMouseDragged(me);
} else if (me.isPrimaryButtonDown()) {
mouseOldX = mousePosX;
mouseOldY = mousePosY;
mousePosX = me.getX();
mousePosY = me.getY();
double mouseDeltaX = (mousePosX - mouseOldX);
double mouseDeltaY = (mousePosY - mouseOldY);
world.rx(mouseDeltaY * 180.0 / subScene.getHeight());
world.ry(-mouseDeltaX * 180.0 / subScene.getWidth());
}
});
subScene.setOnMouseReleased(me -> rs.onMouseDragReleased(me));
subScene.setOnMouseClicked(me -> {
if (me.getButton() == MouseButton.SECONDARY && me.isStillSincePress()) {
rs.clearSelection();
}
});
return subScene;
}
private Pane setupControls() {
Slider zoom = new Slider(-100, 0, -50);
camera.translateZProperty().bind(zoom.valueProperty());
Button reset = new Button("Reset");
reset.setOnAction(eh -> {
world.reset();
zoom.setValue(-50);
});
HBox controls = new HBox(new Label("Zoom: "), zoom, reset);
AnchorPane anchorPane = new AnchorPane(controls);
anchorPane.setPickOnBounds(false);
return anchorPane;
}
private Collection<Shape3D> createWorld() {
List<Shape3D> shapes = new ArrayList<>();
Random random = new Random(System.currentTimeMillis());
for (int i = 0; i < 4000; i++) {
double x = (random.nextDouble() - 0.5) * 30;
double y = (random.nextDouble() - 0.5) * 30;
double z = (random.nextDouble() - 0.5) * 30;
Sphere point = new Sphere(0.2);
point.setMaterial(new PhongMaterial(Color.SKYBLUE));
point.getTransforms().add(new Translate(x, y, z));
shapes.add(point);
}
return shapes;
}
public static void main(String[] args) {
launch(args);
}
public class XFormWorld extends Group {
Transform rotation = new Rotate();
public XFormWorld() {
getTransforms().addAll(rotation);
}
public void reset() {
rotation = new Rotate();
getTransforms().set(0, rotation);
}
public void rx(double angle) {
Point3D axis = new Point3D(rotation.getMxx(), rotation.getMxy(), rotation.getMxz());
rotation = rotation.createConcatenation(new Rotate(angle, axis));
getTransforms().set(0, rotation);
}
public void ry(double angle) {
Point3D axis = new Point3D(rotation.getMyx(), rotation.getMyy(), rotation.getMyz());
rotation = rotation.createConcatenation(new Rotate(angle, axis));
getTransforms().set(0, rotation);
}
}
public class RectangleSelect {
private static final int START_X = 0;
private static final int START_Y = 1;
private static final int END_X = 2;
private static final int END_Y = 3;
private double[] sceneCoords = new double[2]; //mouse drag x, y in scene coords
private double[] screenCoords = new double[2]; //mouse drag current x, y in screen coords
private double[] boundsInScreenCoords = new double[4]; //top left x, y, bottom right x,y in screen coords
private Collection<Shape3D> world;
private PhongMaterial selected = new PhongMaterial(Color.YELLOW);
private Rectangle rectangle;
public RectangleSelect(Pane pane, Collection<Shape3D> world) {
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
rectangle = new Rectangle();
rectangle.setStroke(Color.RED);
rectangle.setOpacity(0.0);
rectangle.setMouseTransparent(true);
rectangle.setFill(null);
this.world = world;
pane.getChildren().add(rectangle);
}
public void onMouseDragged(MouseEvent me) {
clearSelection();
if (sceneCoords[START_X] == Double.MIN_VALUE) {
sceneCoords[START_X] = me.getSceneX();
sceneCoords[START_Y] = me.getSceneY();
screenCoords[START_X] = me.getScreenX();
screenCoords[START_Y] = me.getScreenY();
}
double sceneX = me.getSceneX();
double sceneY = me.getSceneY();
double screenX = me.getScreenX();
double screenY = me.getScreenY();
double topX = Math.min(sceneCoords[START_X], sceneX);
double bottomX = Math.max(sceneCoords[START_X], sceneX);
double leftY = Math.min(sceneCoords[START_Y], sceneY);
double rightY = Math.max(sceneCoords[START_Y], sceneY);
boundsInScreenCoords[START_X] = Math.min(screenCoords[START_X], screenX);
boundsInScreenCoords[END_X] = Math.max(screenCoords[START_X], screenX);
boundsInScreenCoords[START_Y] = Math.min(screenCoords[START_Y], screenY);
boundsInScreenCoords[END_Y] = Math.max(screenCoords[START_Y], screenY);
world.forEach(this::selectIfInBounds);
rectangle.setX(topX);
rectangle.setY(leftY);
rectangle.setWidth(bottomX - topX);
rectangle.setHeight(rightY - leftY);
rectangle.setOpacity(1.0);
}
private void selectIfInBounds(Shape3D node) {
Point2D screenCoods = node.localToScreen(0.0, 0.0, 0.0);
if (screenCoods.getX() > boundsInScreenCoords[START_X] &&
screenCoods.getY() > boundsInScreenCoords[START_Y] &&
screenCoods.getX() < boundsInScreenCoords[END_X] &&
screenCoods.getY() < boundsInScreenCoords[END_Y]) {
Material m = node.getMaterial();
node.getProperties().put("material", m);
node.setMaterial(selected);
}
}
private void unselect(Shape3D node) {
Material m = (Material) node.getProperties().get("material");
if (m != null) {
node.setMaterial(m);
}
}
public void onMouseDragReleased(MouseEvent me) {
rectangle.setOpacity(0.0);
sceneCoords[START_X] = Double.MIN_VALUE;
sceneCoords[START_Y] = Double.MIN_VALUE;
}
public void clearSelection() {
world.forEach(this::unselect);
}
}
}