PathLayer, VectorLayer (polygon) overlays touch events #316 #424 (#425)

vtm/src/org/oscim/layers/PathLayer.java

@@ -1,7 +1,7 @@
 /*
  * Copyright 2012 osmdroid authors: Viesturs Zarins, Martin Pearman
  * Copyright 2012 Hannes Janetzek
- * Copyright 2016 devemux86
+ * Copyright 2016-2017 devemux86
  * Copyright 2016 Bezzu
  * Copyright 2016 Pedinel
  * Copyright 2017 Andrey Novikov
@@ -21,12 +21,17 @@
  */
 package org.oscim.layers;
 
+import org.oscim.backend.CanvasAdapter;
 import org.oscim.backend.canvas.Paint.Cap;
 import org.oscim.core.GeoPoint;
 import org.oscim.core.GeometryBuffer;
 import org.oscim.core.MapPosition;
 import org.oscim.core.MercatorProjection;
+import org.oscim.core.Point;
 import org.oscim.core.Tile;
+import org.oscim.event.Gesture;
+import org.oscim.event.GestureListener;
+import org.oscim.event.MotionEvent;
 import org.oscim.map.Map;
 import org.oscim.renderer.BucketRenderer;
 import org.oscim.renderer.GLViewport;
@@ -34,6 +39,7 @@ import org.oscim.renderer.bucket.LineBucket;
 import org.oscim.renderer.bucket.RenderBuckets;
 import org.oscim.theme.styles.LineStyle;
 import org.oscim.utils.FastMath;
+import org.oscim.utils.GeoPointUtils;
 import org.oscim.utils.async.SimpleWorker;
 import org.oscim.utils.geom.LineClipper;
 
@@ -44,7 +50,7 @@ import java.util.List;
 /**
  * This class draws a path line in given color or texture.
  */
-public class PathLayer extends Layer {
+public class PathLayer extends Layer implements GestureListener {
 
     /**
      * Stores points, converted to the map projection.
@@ -52,6 +58,9 @@ public class PathLayer extends Layer {
     protected final ArrayList<GeoPoint> mPoints;
     protected boolean mUpdatePoints;
 
+    private final Point mPoint1 = new Point();
+    private final Point mPoint2 = new Point();
+
     /**
      * Line style
      */
@@ -437,4 +446,26 @@ public class PathLayer extends Layer {
             return i;
         }
     }
+
+    public synchronized boolean contains(float x, float y) {
+        // Touch min 20 px at baseline mdpi (160dpi)
+        double distance = Math.max(20 / 2 * CanvasAdapter.getScale(), mLineStyle.width);
+        for (int i = 0; i < mPoints.size() - 1; i++) {
+            if (i == 0)
+                mMap.viewport().toScreenPoint(mPoints.get(i), false, mPoint1);
+            else {
+                mPoint1.x = mPoint2.x;
+                mPoint1.y = mPoint2.y;
+            }
+            mMap.viewport().toScreenPoint(mPoints.get(i + 1), false, mPoint2);
+            if (GeoPointUtils.distanceSegmentPoint(mPoint1.x, mPoint1.y, mPoint2.x, mPoint2.y, x, y) <= distance)
+                return true;
+        }
+        return false;
+    }
+
+    @Override
+    public boolean onGesture(Gesture g, MotionEvent e) {
+        return false;
+    }
 }

vtm/src/org/oscim/utils/GeoPointUtils.java

@@ -15,12 +15,14 @@
 package org.oscim.utils;
 
 import org.oscim.core.GeoPoint;
+import org.oscim.core.Point;
 
 public final class GeoPointUtils {
 
     /**
-     * Find if the given point lies within this polygon.<br/>
-     * See http://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html
+     * Find if the given point lies within this polygon.
+     * <p>
+     * http://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html
      *
      * @return true if this polygon contains the given point, false otherwise.
      */
@@ -36,6 +38,16 @@ public final class GeoPointUtils {
         return result;
     }
 
+    /**
+     * Returns the distance between the given segment and point.
+     * <p>
+     * libGDX (Apache 2.0)
+     */
+    public static double distanceSegmentPoint(double startX, double startY, double endX, double endY, double pointX, double pointY) {
+        Point nearest = nearestSegmentPoint(startX, startY, endX, endY, pointX, pointY);
+        return Math.hypot(nearest.x - pointX, nearest.y - pointY);
+    }
+
     /**
      * Find if this way is closed.
      *
@@ -45,6 +57,22 @@ public final class GeoPointUtils {
         return geoPoints[0].distance(geoPoints[geoPoints.length - 1]) < 0.000000001;
     }
 
+    /**
+     * Returns a point on the segment nearest to the specified point.
+     * <p>
+     * libGDX (Apache 2.0)
+     */
+    public static Point nearestSegmentPoint(double startX, double startY, double endX, double endY, double pointX, double pointY) {
+        double xDiff = endX - startX;
+        double yDiff = endY - startY;
+        double length2 = xDiff * xDiff + yDiff * yDiff;
+        if (length2 == 0) return new Point(startX, startY);
+        double t = ((pointX - startX) * (endX - startX) + (pointY - startY) * (endY - startY)) / length2;
+        if (t < 0) return new Point(startX, startY);
+        if (t > 1) return new Point(endX, endY);
+        return new Point(startX + t * (endX - startX), startY + t * (endY - startY));
+    }
+
     private GeoPointUtils() {
         throw new IllegalStateException();
     }