Changeset 4541 in josm

Timestamp:

2011-10-24T21:27:10+02:00 (13 years ago)

Author:

Don-vip

Message:

Fixed rounding error in LatLon.roundToOsmPrecision()

Location:

trunk

Files:

• src/org/openstreetmap/josm/data/coor/LatLon.java (modified) (4 diffs)
• test/unit/org/openstreetmap/josm/data/coor (added)
• test/unit/org/openstreetmap/josm/data/coor/LatLonTest.java (added)

trunk/src/org/openstreetmap/josm/data/coor/LatLon.java

@@ -12 +12 @@
 import static java.lang.Math.toRadians;
 
+import java.math.BigDecimal;
+import java.math.MathContext;
 import java.text.DecimalFormat;
 import java.text.NumberFormat;
@@ -28 +30 @@
 public class LatLon extends Coordinate {
 
+    
     /**
      * Minimum difference in location to not be represented as the same position.
@@ -33 +36 @@
      */
     public static final double MAX_SERVER_PRECISION = 1e-7;
+    public static final int    MAX_SERVER_DIGITS = 7;
 
     private static DecimalFormat cDmsMinuteFormatter = new DecimalFormat("00");
@@ -240 +244 @@
      */
     public static double roundToOsmPrecision(double value) {
-        return Math.round(value / MAX_SERVER_PRECISION) * MAX_SERVER_PRECISION;
+        double absV = Math.abs(value);
+        int numOfDigits = MAX_SERVER_DIGITS + (absV < 1 ? 0 : (absV < 10 ? 1 : (absV < 100 ? 2 : 3))); 
+        return BigDecimal.valueOf(value).round(new MathContext(numOfDigits)).doubleValue();
+        //return Math.round(value / MAX_SERVER_PRECISION) * MAX_SERVER_PRECISION; // Old method, causes rounding errors (see LatLonTest) !
     }