diff --git a/src/com/annimon/graphics/Clip.java b/src/com/annimon/graphics/Clip.java
index 25ba74f..f3040ae 100644
--- a/src/com/annimon/graphics/Clip.java
+++ b/src/com/annimon/graphics/Clip.java
@@ -3,7 +3,7 @@ package com.annimon.graphics;
 /**
  * @author aNNiMON
  */
-public class Clip extends Rect {
+public class Clip extends Rect implements Clippable {
     
     public Clip(double x, double y, double width, double height) {
         super(x, y, width, height);
@@ -24,6 +24,7 @@ public class Clip extends Rect {
         return y + height;
     }
     
+    @Override
     public double[] clip(double x1, double y1, double x2, double y2) {
         int c1 = getClipCode(x1, y1);
         int c2 = getClipCode(x2, y2);
@@ -68,7 +69,7 @@ public class Clip extends Rect {
         return new double[] { x1, y1, x2, y2 };
     }
     
-    public int getClipCode(double x, double y) {
+    private int getClipCode(double x, double y) {
         int xmin = (x < super.x) ? 1 : 0;
         int xmax = (x > getXMax()) ? 1 : 0;
         int ymin = (y < super.y) ? 1 : 0;
diff --git a/src/com/annimon/graphics/PolygonClip.java b/src/com/annimon/graphics/PolygonClip.java
index 1f60fd4..22df2cb 100644
--- a/src/com/annimon/graphics/PolygonClip.java
+++ b/src/com/annimon/graphics/PolygonClip.java
@@ -4,7 +4,7 @@ package com.annimon.graphics;
  *
  * @author aNNiMON
  */
-public class PolygonClip extends Clip {
+public class PolygonClip extends Clip implements Clippable {
     
     private final Polygon poly;
 
@@ -54,11 +54,11 @@ public class PolygonClip extends Clip {
         Point dirV = new Point(p2.getX() - p1.getX(), p2.getY() - p1.getY());
         Point F = new Point();
         boolean visible = true;
-        int i = 0;
+        int i = 0; 
         while ((i < poly.nPoints) && visible) {
             F.setX(p1.getX() - poly.v[i].getX());
             F.setY(p1.getY() - poly.v[i].getY());
-            
+                                                
             double num = pointProduction(n[i], F);
             double den = pointProduction(n[i], dirV);