diff --git a/core/.gitignore b/core/.gitignore
index 8a42e92..1c87580 100644
--- a/core/.gitignore
+++ b/core/.gitignore
@@ -18,3 +18,4 @@
 /textRenderer.class
 /texture.class
 /vector.class
+/mainThread$MathOperation.class
diff --git a/core/grid.java b/core/grid.java
index 91b7a68..100506c 100644
--- a/core/grid.java
+++ b/core/grid.java
@@ -54,7 +54,6 @@ public class grid {
 		}
 	}
 	
-	
 }
 
 
diff --git a/core/polygon3D.java b/core/polygon3D.java
index 930db3f..1d9903c 100644
--- a/core/polygon3D.java
+++ b/core/polygon3D.java
@@ -49,7 +49,7 @@ public class polygon3D {
 	public solidObject parentObject;
 	
 	//A pool of vectors which will be used for vector arithmetic
-	public  vector 
+	public  static vector 
 		tempVector1 = new vector(0,0,0),
 		tempVector2 = new vector(0,0,0),
 		tempVector3 = new vector(0,0,0),
@@ -83,7 +83,7 @@ public class polygon3D {
 	public byte[] diffuse = new byte[3];
 	
 	//default light source
-	public vector lightDirection = sunLight.lightDirection;
+	public static vector lightDirection = sunLight.lightDirection;
 	
 	//the color of polygon if it is defined as soild 
 	public int color;
diff --git a/enemyAI/enemyCommander.java b/enemyAI/enemyCommander.java
index 1e779a1..530a6cc 100644
--- a/enemyAI/enemyCommander.java
+++ b/enemyAI/enemyCommander.java
@@ -60,7 +60,7 @@ public class enemyCommander {
 		thinkHardLikeHumanPlayer();
 		
 		
-		drawVisionMap();
+		//drawVisionMap();
 		
 		//reset tempBitmap;
 		for(int i = 0 ;i < tempBitmap.length; i++){