Merge remote-tracking branch 'origin/feature/select-drag-listener' into develop

# Conflicts:
#	worldwind-examples/src/main/java/gov/nasa/worldwindx/OmnidirectionalSightlineActivity.java
#	worldwind-examples/src/main/java/gov/nasa/worldwindx/PlacemarksSelectDragActivity.java

Author: EMaksymenko

worldwind-examples/src/main/java/gov/nasa/worldwindx/OmnidirectionalSightlineActivity.java

@@ -5,24 +5,16 @@
 
 package gov.nasa.worldwindx;
 
-import android.graphics.PointF;
 import android.os.Bundle;
-import android.view.GestureDetector;
-import android.view.MotionEvent;
-
 import gov.nasa.worldwind.BasicWorldWindowController;
-import gov.nasa.worldwind.PickedObject;
-import gov.nasa.worldwind.PickedObjectList;
 import gov.nasa.worldwind.WorldWind;
-import gov.nasa.worldwind.WorldWindow;
-import gov.nasa.worldwind.geom.Line;
 import gov.nasa.worldwind.geom.LookAt;
 import gov.nasa.worldwind.geom.Position;
-import gov.nasa.worldwind.geom.Vec3;
-import gov.nasa.worldwind.globe.Globe;
+import gov.nasa.worldwind.gesture.SelectDragCallback;
 import gov.nasa.worldwind.layer.RenderableLayer;
 import gov.nasa.worldwind.render.Color;
 import gov.nasa.worldwind.render.ImageSource;
+import gov.nasa.worldwind.render.Renderable;
 import gov.nasa.worldwind.shape.OmnidirectionalSightline;
 import gov.nasa.worldwind.shape.Placemark;
 import gov.nasa.worldwind.shape.ShapeAttributes;
@@ -45,11 +37,6 @@ public class OmnidirectionalSightlineActivity extends BasicGlobeActivity {
      */
     protected Placemark sightlinePlacemark;
 
-    /**
-     * A custom WorldWindowController object that handles the select, drag and navigation gestures.
-     */
-    protected SimpleSelectDragNavigateController controller;
-
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -83,152 +70,22 @@ protected void onCreate(Bundle savedInstanceState) {
         sightlineLayer.addRenderable(this.sightlinePlacemark);
         this.wwd.getLayers().addLayer(sightlineLayer);
 
-        // Override the WorldWindow's built-in navigation behavior with conditional dragging support.
-        this.controller = new SimpleSelectDragNavigateController(this.wwd);
-        this.wwd.setWorldWindowController(this.controller);
-
-        // And finally, for this demo, position the viewer to look at the sightline position
-        LookAt lookAt = new LookAt().set(pos.latitude, pos.longitude, pos.altitude, WorldWind.ABSOLUTE, 2e4 /*range*/, 0 /*heading*/, 45 /*tilt*/, 0 /*roll*/);
-        this.getWorldWindow().cameraFromLookAt(lookAt);
-    }
-
-    /**
-     * This inner class is based on the controller in the {@link PlacemarksSelectDragActivity} but has been simplified
-     * for the single Placemark.
-     */
-    public class SimpleSelectDragNavigateController extends BasicWorldWindowController {
-
-        protected boolean isDragging = false;
-
-        protected boolean isDraggingArmed = false;
-
-        private final PointF dragRefPt = new PointF();
-
-        /**
-         * Pre-allocated to avoid memory allocations
-         */
-        private final Line ray = new Line();
-
-        /**
-         * Pre-allocated to avoid memory allocations
-         */
-        private final Vec3 pickPoint = new Vec3();
-
-        /**
-         * Assign a subclassed SimpleOnGestureListener to a GestureDetector to handle the drag gestures.
-         */
-        protected final GestureDetector selectDragDetector = new GestureDetector(getApplicationContext(), new GestureDetector.SimpleOnGestureListener() {
-
+        // Add dragging callback
+        ((BasicWorldWindowController) wwd.getWorldWindowController()).setSelectDragCallback(new SelectDragCallback() {
             @Override
-            public boolean onDown(MotionEvent event) {
-                pick(event);    // Pick the object(s) at the tap location
-                return false;   // By not consuming this event, we allow it to pass on to the navigation gesture handlers
+            public boolean canMoveRenderable(Renderable renderable) {
+                return renderable == sightlinePlacemark;
             }
 
             @Override
-            public boolean onScroll(MotionEvent downEvent, MotionEvent moveEvent, float distanceX, float distanceY) {
-                if (isDraggingArmed) {
-                    return drag(distanceX, distanceY);
-                }
-                return false;
+            public void onRenderableMoved(Renderable renderable, Position fromPosition, Position toPosition) {
+                sightline.setPosition(toPosition);
             }
         });
 
-        public SimpleSelectDragNavigateController(WorldWindow wwd) {
-            super(wwd);
-        }
-
-        /**
-         * Delegates events to the select/drag handlers or the native World Wind navigation handlers.
-         */
-        @Override
-        public boolean onTouchEvent(MotionEvent event) {
-            // Allow our select and drag handlers to process the event first. They'll set the state flags which will
-            // either preempt or allow the event to be subsequently processed by the globe's navigation event handlers.
-            boolean consumed = this.selectDragDetector.onTouchEvent(event);
-
-            // Is a dragging operation started or in progress? Any ACTION_UP event cancels a drag operation.
-            if (this.isDragging && event.getAction() == MotionEvent.ACTION_UP) {
-                this.isDragging = false;
-                this.isDraggingArmed = false;
-            }
-            // Preempt the globe's pan navigation recognizer if we're dragging
-            super.panRecognizer.setEnabled(!isDragging);
-
-            // Pass on the event on to the default globe navigation handlers
-            if (!consumed) {
-                consumed = super.onTouchEvent(event);
-            }
-            return consumed;
-        }
-
-        /**
-         * Moves the selected object to the event's screen position.
-         *
-         * @return true if the event was consumed
-         */
-        public boolean drag(float distanceX, float distanceY) {
-            if (this.isDraggingArmed) {
-                // Signal that dragging is in progress
-                this.isDragging = true;
-
-                // First we compute the screen coordinates of the position's "ground" point.  We'll apply the
-                // screen X and Y drag distances to this point, from which we'll compute a new position,
-                // wherein we restore the original position's altitude.
-                Position position = sightlinePlacemark.getReferencePosition();
-                double altitude = position.altitude;
-                if (getWorldWindow().geographicToScreenPoint(position.latitude, position.longitude, 0, this.dragRefPt)) {
-                    // Update the placemark's ground position
-                    if (screenPointToGroundPosition(this.dragRefPt.x - distanceX, this.dragRefPt.y - distanceY, position)) {
-                        // Restore the placemark's original altitude
-                        position.altitude = altitude;
-                        // Move the sightline
-                        sightline.setPosition(position);
-                        // Reflect the change in position on the globe.
-                        getWorldWindow().requestRedraw();
-                        return true;
-                    }
-                }
-                // Probably clipped by near/far clipping plane or off the globe. The position was not updated. Stop the drag.
-                this.isDraggingArmed = false;
-                return true; // We consumed this event, even if dragging has been stopped.
-            }
-            return false;
-        }
-
-        /**
-         * Performs a pick at the tap location and conditionally arms the dragging flag, so that dragging can occur if
-         * the next event is an onScroll event.
-         */
-        public void pick(MotionEvent event) {
-
-            // Perform the pick at the screen x, y
-            PickedObjectList pickList = getWorldWindow().pick(event.getX(), event.getY());
-
-            // Examine the picked objects for Renderables
-            PickedObject topPickedObject = pickList.topPickedObject();
-            // There is only one placemark on the globe and
-            this.isDraggingArmed = topPickedObject != null && topPickedObject.getUserObject() instanceof Placemark;
-        }
-
-        /**
-         * Converts a screen point to the geographic coordinates on the globe.
-         *
-         * @param screenX X coordinate
-         * @param screenY Y coordinate
-         * @param result  Pre-allocated Position receives the geographic coordinates
-         *
-         * @return true if the screen point could be converted; false if the screen point is not on the globe
-         */
-        public boolean screenPointToGroundPosition(float screenX, float screenY, Position result) {
-            if (this.wwd.rayThroughScreenPoint(screenX, screenY, ray)) {
-                Globe globe = wwd.getGlobe();
-                if (globe.intersect(ray, this.pickPoint)) {
-                    globe.cartesianToGeographic(pickPoint.x, this.pickPoint.y, this.pickPoint.z, result);
-                    return true;
-                }
-            }
-            return false;
-        }
+        // And finally, for this demo, position the viewer to look at the sightline position
+        LookAt lookAt = new LookAt().set(pos.latitude, pos.longitude, pos.altitude, WorldWind.ABSOLUTE, 2e4 /*range*/, 0 /*heading*/, 45 /*tilt*/, 0 /*roll*/);
+        this.getWorldWindow().cameraFromLookAt(lookAt);
     }
+
 }