[Hipgmap-cvs] gmap/com/trileet/gmap Point.java,1.3,1.4

[Adam B. <ab...@us...>]

Update of /cvsroot/hipgmap/gmap/com/trileet/gmap
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv15703

Modified Files:
	Point.java 
Log Message:
You can now ask a Point for its KeyHole (KH) coordinates.  See the
wiki for discussions of this.  Next I'm going to start playing with
some of the Photo tiles....



Index: Point.java
===================================================================
RCS file: /cvsroot/hipgmap/gmap/com/trileet/gmap/Point.java,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** Point.java	3 Apr 2005 11:21:53 -0000	1.3
--- Point.java	6 Apr 2005 23:39:42 -0000	1.4
***************
*** 81,91 ****
      }
  
      public static void main(String[] argv) {
  	// A little test routine
! 	Point p = new Point(3256000,-11824000);
! 	System.out.println(p.toString());
! 	Point q = fromString(p.toString());
! 	System.out.println(q.toString());
! 	System.out.println(q.lat.toString());
      }
  }
--- 81,115 ----
      }
  
+     /**
+      * We can convert the point's lat/lng to KeyHole (KH) coordinates.
+      * See Eric's writeup of the KH system on the wiki, and my
+      * explanation of the algorithm on the talk:Satellite page.
+      */
+ 
+     private static final hipfloat h180 = new hipfloat(180);
+     private static final hipfloat h360 = new hipfloat(360);
+     private static final hipfloat h2p18 = new hipfloat(1<<19);
+     private static final char[] KHCHARS = {'t','q','s','r'};
+     public static String latLngToKH(hipfloat lat, hipfloat lng) {
+ 	int y = lat.add(h180).div(h360).mul(h2p18).toint();
+ 	int x = lng.add(h180).div(h360).mul(h2p18).toint();
+ 
+ 	char[] outArr = new char[20];
+ 	for (int i=0; i<19; i++) {
+ 	    int index = ((x & 1<<(19-i))>>(18-i));
+ 	    index |= ((y & 1<<(19-i))>>(19-i));
+ 	    outArr[i] = KHCHARS[index];
+ 	}
+ 	return new String(outArr);
+ 	//return String.valueOf(x) + " " + String.valueOf(y);	
+     }
+     public String getKH() {
+ 	return latLngToKH(this.lat,this.lng);
+     }
+ 
      public static void main(String[] argv) {
  	// A little test routine
! 	Point p = new Point(3787206,-12227688);
! 	System.out.println(p.getKH());
      }
  }