fix issue 1559 (TestSoftwareMouse misbehaves with LWJGL v3)

jme3-examples/src/main/java/jme3test/gui/TestSoftwareMouse.java

@@ -36,6 +36,7 @@ import com.jme3.app.SimpleApplication;
 import com.jme3.input.RawInputListener;
 import com.jme3.input.event.*;
 import com.jme3.math.FastMath;
+import com.jme3.math.Vector2f;
 import com.jme3.system.AppSettings;
 import com.jme3.texture.Texture;
 import com.jme3.texture.Texture2D;
@@ -47,8 +48,6 @@ public class TestSoftwareMouse extends SimpleApplication {
 
     final private RawInputListener inputListener = new RawInputListener() {
 
-        private float x = 0, y = 0;
-
         @Override
         public void beginInput() {
         }
@@ -63,8 +62,8 @@ public class TestSoftwareMouse extends SimpleApplication {
         }
         @Override
         public void onMouseMotionEvent(MouseMotionEvent evt) {
-            x += evt.getDX();
-            y += evt.getDY();
+            float x = evt.getX();
+            float y = evt.getY();
 
             // Prevent mouse from leaving screen
             AppSettings settings = TestSoftwareMouse.this.settings;
@@ -107,6 +106,12 @@ public class TestSoftwareMouse extends SimpleApplication {
         cursor.setWidth(64);
         cursor.setHeight(64);
         guiNode.attachChild(cursor);
+        /*
+         * Position the software cursor
+         * so that its upper-left corner is at the hotspot.
+         */
+        Vector2f initialPosition = inputManager.getCursorPosition();
+        cursor.setPosition(initialPosition.x, initialPosition.y - 64f);
 
         inputManager.addRawInputListener(inputListener);