Changeset 5125 in josm for trunk/src/org/openstreetmap/josm/actions/AlignInCircleAction.java

Timestamp:

2012-03-26T21:26:51+02:00 (14 years ago)

Author:

Don-vip

Message:

Make polygon centroid computation a public method in Geometry class

File:

• trunk/src/org/openstreetmap/josm/actions/AlignInCircleAction.java (modified) (2 diffs)

trunk/src/org/openstreetmap/josm/actions/AlignInCircleAction.java

@@ -23 +23 @@
 import org.openstreetmap.josm.data.osm.OsmPrimitive;
 import org.openstreetmap.josm.data.osm.Way;
+import org.openstreetmap.josm.tools.Geometry;
 import org.openstreetmap.josm.tools.Shortcut;
 
@@ -184 +185 @@
         if (center == null) {
             // Compute the centroid of nodes
-
-            BigDecimal area = new BigDecimal(0);
-            BigDecimal north = new BigDecimal(0);
-            BigDecimal east = new BigDecimal(0);
-
-            // See http://en.wikipedia.org/w/index.php?title=Centroid&oldid=294224857#Centroid_of_polygon for the equation used here
-            for (int i = 0; i < nodes.size(); i++) {
-                EastNorth n0 = nodes.get(i).getEastNorth();
-                EastNorth n1 = nodes.get((i+1) % nodes.size()).getEastNorth();
-
-                BigDecimal x0 = new BigDecimal(n0.east());
-                BigDecimal y0 = new BigDecimal(n0.north());
-                BigDecimal x1 = new BigDecimal(n1.east());
-                BigDecimal y1 = new BigDecimal(n1.north());
-
-                BigDecimal k = x0.multiply(y1, MathContext.DECIMAL128).subtract(y0.multiply(x1, MathContext.DECIMAL128));
-
-                area = area.add(k, MathContext.DECIMAL128);
-                east = east.add(k.multiply(x0.add(x1, MathContext.DECIMAL128), MathContext.DECIMAL128));
-                north = north.add(k.multiply(y0.add(y1, MathContext.DECIMAL128), MathContext.DECIMAL128));
-
-            }
-
-            BigDecimal d = new BigDecimal(3, MathContext.DECIMAL128); // 1/2 * 6 = 3
-            area  = area.multiply(d, MathContext.DECIMAL128);
-            north = north.divide(area, MathContext.DECIMAL128);
-            east = east.divide(area, MathContext.DECIMAL128);
-
-            center = new EastNorth(east.doubleValue(), north.doubleValue());
-
+            center = Geometry.getCentroid(nodes);
         }
         // Node "center" now is central to all selected nodes.