Add native touch rotation to FlyByCamera

jme3-core/src/main/java/com/jme3/input/FlyByCamera.java

@@ -37,6 +37,9 @@
 import com.jme3.input.controls.KeyTrigger;
 import com.jme3.input.controls.MouseAxisTrigger;
 import com.jme3.input.controls.MouseButtonTrigger;
+import com.jme3.input.controls.TouchListener;
+import com.jme3.input.controls.TouchTrigger;
+import com.jme3.input.event.TouchEvent;
 import com.jme3.math.Matrix3f;
 import com.jme3.math.Quaternion;
 import com.jme3.math.Vector3f;
@@ -54,12 +57,14 @@
  *  - WASD keys for moving forward/backward and strafing
  *  - QZ keys raise or lower the camera
  */
-public class FlyByCamera implements AnalogListener, ActionListener, JoystickConnectionListener {
+public class FlyByCamera implements AnalogListener, ActionListener, JoystickConnectionListener, TouchListener {
 
     private static final String FLYCAM_JOYSTICK_LEFT = "FLYCAM_JoystickLeft";
     private static final String FLYCAM_JOYSTICK_RIGHT = "FLYCAM_JoystickRight";
     private static final String FLYCAM_JOYSTICK_UP = "FLYCAM_JoystickUp";
     private static final String FLYCAM_JOYSTICK_DOWN = "FLYCAM_JoystickDown";
+    private static final String FLYCAM_TOUCH = "FLYCAM_Touch";
+    private static final float TOUCH_ROTATION_SCALE = 1f / 1024f;
 
     private static final String[] mappings = new String[]{
             CameraInput.FLYCAM_LEFT,
@@ -84,7 +89,8 @@ public class FlyByCamera implements AnalogListener, ActionListener, JoystickConn
             FLYCAM_JOYSTICK_LEFT,
             FLYCAM_JOYSTICK_RIGHT,
             FLYCAM_JOYSTICK_UP,
-            FLYCAM_JOYSTICK_DOWN
+            FLYCAM_JOYSTICK_DOWN,
+            FLYCAM_TOUCH
     };
     /**
      * camera controlled by this controller (not null)
@@ -306,6 +312,7 @@ private void registerInputMappings() {
         inputManager.addMapping(CameraInput.FLYCAM_ZOOMIN, new MouseAxisTrigger(MouseInput.AXIS_WHEEL, false));
         inputManager.addMapping(CameraInput.FLYCAM_ZOOMOUT, new MouseAxisTrigger(MouseInput.AXIS_WHEEL, true));
         inputManager.addMapping(CameraInput.FLYCAM_ROTATEDRAG, new MouseButtonTrigger(MouseInput.BUTTON_LEFT));
+        inputManager.addMapping(FLYCAM_TOUCH, new TouchTrigger(TouchInput.ALL));
 
         // keyboard only WASD for movement and WZ for rise/lower height
         inputManager.addMapping(CameraInput.FLYCAM_STRAFELEFT, new KeyTrigger(KeyInput.KEY_A));
@@ -567,4 +574,14 @@ public void onAction(String name, boolean isPressed, float tpf) {
             }
         }
     }
+
+    @Override
+    public void onTouch(String name, TouchEvent event, float tpf) {
+        if (!enabled || !name.equals(FLYCAM_TOUCH) || event.getType() != TouchEvent.Type.MOVE) {
+            return;
+        }
+
+        rotateCamera(-event.getDeltaX() * TOUCH_ROTATION_SCALE, initialUpVec, true);
+        rotateCamera(-event.getDeltaY() * TOUCH_ROTATION_SCALE * (invertY ? -1 : 1), cam.getLeft(tempLeft), true);
+    }
 }

jme3-core/src/test/java/com/jme3/input/FlyByCameraTest.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2026 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.jme3.input;
+
+import com.jme3.input.event.TouchEvent;
+import com.jme3.math.Vector3f;
+import com.jme3.renderer.Camera;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+class FlyByCameraTest {
+
+    @Test
+    void touchDragRotatesCamera() {
+        Camera camera = new Camera(640, 480);
+        FlyByCamera flyCam = new FlyByCamera(camera);
+        Vector3f initialDirection = camera.getDirection().clone();
+
+        flyCam.onTouch("FLYCAM_Touch",
+                new TouchEvent(TouchEvent.Type.MOVE, 0f, 0f, 128f, 0f), 0f);
+
+        assertFalse(initialDirection.equals(camera.getDirection()));
+    }
+
+    @Test
+    void touchDragRotatesCameraWhenDragToRotateIsEnabled() {
+        Camera camera = new Camera(640, 480);
+        FlyByCamera flyCam = new FlyByCamera(camera);
+        flyCam.setDragToRotate(true);
+        Vector3f initialDirection = camera.getDirection().clone();
+
+        flyCam.onTouch("FLYCAM_Touch",
+                new TouchEvent(TouchEvent.Type.MOVE, 0f, 0f, 128f, 0f), 0f);
+
+        assertFalse(initialDirection.equals(camera.getDirection()));
+    }
+
+    @Test
+    void disabledFlyByCameraIgnoresTouchDrag() {
+        Camera camera = new Camera(640, 480);
+        FlyByCamera flyCam = new FlyByCamera(camera);
+        flyCam.setEnabled(false);
+        Vector3f initialDirection = camera.getDirection().clone();
+
+        flyCam.onTouch("FLYCAM_Touch",
+                new TouchEvent(TouchEvent.Type.MOVE, 0f, 0f, 128f, 0f), 0f);
+
+        assertEquals(initialDirection, camera.getDirection());
+    }
+}