diff --git a/README.md b/README.md
index 5a89e54..652b762 100755
--- a/README.md
+++ b/README.md
@@ -12,7 +12,7 @@ Simplification of a 2D-polyline or a 3D-polyline.
   * requires Java 5
   * Maven Build
   * JUnit-tested
-    * 94% lines covered
+    * 100% lines covered
     * reference data is created by "original" JavaScript implementation (Version 1.1.0)
 
 # Example #
diff --git a/src/main/java/com/goebl/simplify/Simplify3D.java b/src/main/java/com/goebl/simplify/Simplify3D.java
index a6e13dd..853378e 100755
--- a/src/main/java/com/goebl/simplify/Simplify3D.java
+++ b/src/main/java/com/goebl/simplify/Simplify3D.java
@@ -65,7 +65,7 @@ public double getSquareDistance(T p1, T p2) {
 
     @Override
     public double getSquareSegmentDistance(T p0, T p1, T p2) {
-        double x0, y0, z0, x1, y1, z1, x2, y2, z2, dx, dy, dz, t;
+        double x0, y0, z0, x1, y1, z1, x2, y2, z2;
 
         x1 = pointExtractor.getX(p1);
         y1 = pointExtractor.getY(p1);
@@ -77,14 +77,20 @@ public double getSquareSegmentDistance(T p0, T p1, T p2) {
         y0 = pointExtractor.getY(p0);
         z0 = pointExtractor.getZ(p0);
 
-        dx = x2 - x1;
-        dy = y2 - y1;
-        dz = z2 - z1;
+        return calculateSquareSegmentDistance(x0, y0, z0, x1, y1, z1, x2, y2, z2);
+    }
+
+    static double calculateSquareSegmentDistance(
+            double x0, double y0, double z0,
+            double x1, double y1, double z1,
+            double x2, double y2, double z2) {
+        double dx = x2 - x1;
+        double dy = y2 - y1;
+        double dz = z2 - z1;
 
         if (dx != 0.0d || dy != 0.0d || dz != 0.0d) {
-            t = ((x0 - x1) * dx + (y0 - y1) * dy + (z0 - z1) * dz)
+            double t = ((x0 - x1) * dx + (y0 - y1) * dy + (z0 - z1) * dz)
                     / (dx * dx + dy * dy + dz * dz);
-
             if (t > 1.0d) {
                 x1 = x2;
                 y1 = y2;
diff --git a/src/test/java/com/goebl/simplify/Simplify3DTest.java b/src/test/java/com/goebl/simplify/Simplify3DTest.java
index 2e5e961..1d75563 100755
--- a/src/test/java/com/goebl/simplify/Simplify3DTest.java
+++ b/src/test/java/com/goebl/simplify/Simplify3DTest.java
@@ -14,6 +14,7 @@ public class Simplify3DTest {
     private static final float[][] POINTS_3D = new float[][]{
             {3.14f, 5.2f, 4f}, {5.7f, 8.1f, 5f}, {4.6f, -1.3f, 6f}
     };
+    private static final double DELTA = 0.00001d;
 
     @Test
     public void testCustomPoint3DExtractor() {
@@ -59,6 +60,20 @@ public void testDefaultPointExtractor() {
         Assert.assertEquals("array should be simplified", 2, simplified.length);
     }
 
+    @Test
+    public void testCalculateSquareSegmentDistance() {
+        double res = Simplify3D.calculateSquareSegmentDistance(
+                2, 1, 1,
+                1, 1, 1,
+                3, 3, 1);
+        Assert.assertEquals(0.5d, res, DELTA);
+        double resBis = Simplify3D.calculateSquareSegmentDistance(
+                -0.1, -0.2, -0.3,
+                -0.7, -0.8, -0.9,
+                -0.4, -0.5, -0.6);
+        Assert.assertEquals(0.27d, resBis, DELTA);
+    }
+
     private static class MyPoint implements Point3D {
         double x;
         double y;
diff --git a/src/test/java/com/goebl/simplify/SimplifyTest.java b/src/test/java/com/goebl/simplify/SimplifyTest.java
index 1fd816e..dd0714d 100755
--- a/src/test/java/com/goebl/simplify/SimplifyTest.java
+++ b/src/test/java/com/goebl/simplify/SimplifyTest.java
@@ -111,9 +111,10 @@ static Point[] readPoints(String fileName) throws Exception {
         List<MyPoint> pointList = new ArrayList<MyPoint>();
         File file = new File("src/test/resources", fileName);
         InputStream is = null;
+        BufferedReader reader = null;
         try {
             is = new FileInputStream(file);
-            BufferedReader reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
+            reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
             String line;
             while ((line = reader.readLine()) != null) {
                 if (line.trim().length() == 0) {
@@ -125,6 +126,9 @@ static Point[] readPoints(String fileName) throws Exception {
                 pointList.add(new MyPoint(x, y));
             }
         } finally {
+            if (reader != null) {
+                reader.close();
+            }
             if (is != null) {
                 is.close();
             }