suspect-manager: dynamic polygon check

brouter-server/src/main/java/btools/server/Polygon.java

@@ -0,0 +1,89 @@
+package btools.server;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.StringTokenizer;
+
+public class Polygon
+{
+  private int[] ax;
+  private int[] ay;
+
+  private int minx = Integer.MAX_VALUE;
+  private int miny = Integer.MAX_VALUE;
+  private int maxx = Integer.MIN_VALUE;
+  private int maxy = Integer.MIN_VALUE;
+
+  public Polygon( BufferedReader br ) throws IOException
+  {
+    ArrayList<String> lines = new ArrayList<String>();
+  
+    for(;;)
+    {
+      String line = br.readLine();
+      if ( line == null || "END".equals( line ) )
+      {
+        break;
+      }
+      lines.add( line );
+    }
+    int n = lines.size();
+    ax = new int[n];
+    ay = new int[n];
+    for( int i=0; i<n; i++ )
+    {
+      String line = lines.get(i);
+      StringTokenizer tk = new StringTokenizer( line );
+      double lon = Double.parseDouble( tk.nextToken() );
+      double lat = Double.parseDouble( tk.nextToken() );
+      
+      int x = ax[i] = (int)(lon*1000000. + 180000000);
+      int y = ay[i] = (int)(lat*1000000. +  90000000);
+      
+      if ( x < minx ) minx = x;
+      if ( y < miny ) miny = y;
+      if ( x > maxx ) maxx = x;
+      if ( y > maxy ) maxy = y;
+    }
+  }
+  
+  public boolean isInPolygon( long id )
+  {
+    int x = (int) ( id >> 32 );
+    int y = (int) ( id & 0xffffffff );
+
+    if ( x < minx || x > maxx || y < miny || y > maxy )
+    {
+      return false;
+    }
+
+    int n = ax.length-1; // these are closed polygons
+
+    boolean inside = false;
+    int j = n - 1;
+    for (int i = 0 ;i < n ; j = i++)
+    {
+      if ( (ay[i] > y) != (ay[j] > y) )
+      {
+        long v = ax[j] - ax[i];
+        v *= y - ay[i];
+        v /= ay[j] - ay[i];
+        if ( x <= v +  ax[i])
+        {
+          inside = !inside;
+        }
+      }
+    }
+    return inside;
+  }
+
+  public boolean isInBoundingBox( long id )
+  {
+    int x = (int) ( id >> 32 );
+    int y = (int) ( id & 0xffffffff );
+
+    return x >= minx && x <= maxx && y >= miny && y <= maxy;
+  }
+
+}