AltosSiteMapTile: adjust centering calculation

diff --git a/ao-tools/altosui/AltosSiteMapTile.java b/ao-tools/altosui/AltosSiteMapTile.java
index 919de825dcfcd476b1f7de0cd5f9312085faaad8..6f5ddede5770f8e5e2b9b86916bbab2a3e6a0bca 100644 (file)
--- a/ao-tools/altosui/AltosSiteMapTile.java
+++ b/ao-tools/altosui/AltosSiteMapTile.java
@@ -52,8 +52,8 @@ public class AltosSiteMapTile extends JLabel {
             if (coord_pt.y - north_1nm.y > px_size/2)
                 break;
         }
             if (coord_pt.y - north_1nm.y > px_size/2)
                 break;
         }

-        coord_pt.x = px_size/2 - ((long)coord_pt.x/px_size + off_x) * px_size;
-        coord_pt.y = px_size/2 - ((long)coord_pt.y/px_size + off_y) * px_size;
+        coord_pt.x = -px_size * Math.floor(coord_pt.x/px_size + off_x);
+        coord_pt.y = -px_size * Math.floor(coord_pt.y/px_size + off_y);

 
         scale_x = 256/360.0 * Math.pow(2, zoom);
         scale_y = 256/(2.0*Math.PI) * Math.pow(2, zoom);
 
         scale_x = 256/360.0 * Math.pow(2, zoom);
         scale_y = 256/(2.0*Math.PI) * Math.pow(2, zoom);