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diff --git a/org.simantics.g3d/src/org/simantics/g3d/math/MathTools.java b/org.simantics.g3d/src/org/simantics/g3d/math/MathTools.java
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+package org.simantics.g3d.math;
+
+import javax.vecmath.AxisAngle4d;
+import javax.vecmath.Matrix3d;
+import javax.vecmath.Matrix4d;
+import javax.vecmath.Quat4d;
+import javax.vecmath.Tuple3d;
+import javax.vecmath.Tuple4d;
+import javax.vecmath.Vector2f;
+import javax.vecmath.Vector3d;
+
+import org.simantics.g3d.math.EulerTools.Order;
+
+
+/**
+ * Some useful geometry related math functions. Beware, methods may modify their input parameters!
+ * 
+ * @author Marko Luukkainen
+ *
+ */
+public class MathTools {
+    
+    public static double NEAR_ZERO = 0.0000001;
+    public static double NEAR_HALF = 0.4999999;
+    
+    public static final Vector3d Z_AXIS = new Vector3d(0.0,0.0,1.0);
+	public static final Vector3d Y_AXIS = new Vector3d(0.0,1.0,0.0);
+	public static final Vector3d X_AXIS = new Vector3d(1.0,0.0,0.0);
+	public static final Vector3d ORIGIN = new Vector3d(0.0,0.0,0.0);
+	
+	final static double EPS = 1.0e-12;
+	
+	
+	public static boolean equals(double d1, double d2) {
+		return Math.abs(d1-d2) < EPS;
+	}
+	
+	public static boolean equals(Tuple3d p1, Tuple3d p2) {
+		return distanceSquared(p1, p2) < NEAR_ZERO;
+	}
+	
+	public static boolean equals(Tuple4d p1, Tuple4d p2) {
+		return distanceSquared(p1, p2) < NEAR_ZERO;
+	}
+	
+	public static double distance(Tuple3d p1, Tuple3d p2) {
+		double dx, dy, dz;
+
+		dx = p2.x - p1.x;
+		dy = p2.y - p1.y;
+		dz = p2.z - p1.z;
+		return Math.sqrt(dx*dx+dy*dy+dz*dz);
+	}
+	
+	public static double distance(Tuple4d p1, Tuple4d p2) {
+		double dx, dy, dz, dw;
+
+		dx = p2.x - p1.x;
+		dy = p2.y - p1.y;
+		dz = p2.z - p1.z;
+		dw = p2.w - p1.w;
+		return Math.sqrt(dx*dx+dy*dy+dz*dz+dw*dw);
+	}
+	
+	public static double distanceSquared(Tuple3d p1, Tuple3d p2) {
+		double dx, dy, dz;
+
+		dx = p2.x - p1.x;
+		dy = p2.y - p1.y;
+		dz = p2.z - p1.z;
+		return dx*dx+dy*dy+dz*dz;
+	}
+	
+	public static double distanceSquared(Tuple4d p1, Tuple4d p2) {
+		double dx, dy, dz, dw;
+
+		dx = p2.x - p1.x;
+		dy = p2.y - p1.y;
+		dz = p2.z - p1.z;
+		dw = p2.w - p1.w;
+		return dx*dx+dy*dy+dz*dz+dw*dw;
+	}
+	
+	public static boolean isValid(Tuple3d t) {
+		return !(Double.isInfinite(t.x) || Double.isNaN(t.x) ||
+				 Double.isInfinite(t.y) || Double.isNaN(t.y) ||
+				 Double.isInfinite(t.z) || Double.isNaN(t.z));
+	}
+    
+    public static Vector3d closestPointOnEdge(Vector3d point, Vector3d edgePoint1, Vector3d edgePoint2) {
+        point.sub(edgePoint1);
+        Vector3d v = new Vector3d(edgePoint2);
+        v.sub(edgePoint1);
+        double t = v.dot(point);
+        t /= v.lengthSquared();
+        if (t <= 0.0f)
+          return edgePoint1;
+        if (t >= 1.0f)
+          return edgePoint2;
+        v.scale(t);
+        v.add(edgePoint1);
+        return v;   
+    }
+    
+    public static Vector3d closestPointOnStraight(Tuple3d point, Tuple3d straightPoint, Vector3d straightDir) {
+        Vector3d v = new Vector3d(point);
+        v.sub(straightPoint);
+        double t = straightDir.dot(v);
+        t /= straightDir.lengthSquared();
+        v.set(straightDir);
+        v.scale(t);
+        v.add(straightPoint);
+        return v;   
+    }
+    
+    public static Vector3d closestPointOnStraight(Tuple3d point, Tuple3d straightPoint, Vector3d straightDir, double u[]) {
+        Vector3d v = new Vector3d(point);
+        v.sub(straightPoint);
+        u[0] = straightDir.dot(v);
+        u[0] /= straightDir.lengthSquared();
+        v.set(straightDir);
+        v.scale(u[0]);
+        v.add(straightPoint);
+        return v;   
+    }
+    
+    public static double distanceFromPlane(Vector3d point, Vector3d planeNormal, Tuple3d planePoint) {
+        point.sub(planePoint);
+        
+        return planeNormal.dot(point);
+    }
+      
+    public static double distanceFromPlane(Vector3d point, Vector3d planeNormal, float d) {
+        return (planeNormal.dot(point) + d);
+    }
+    
+    public static boolean intersectStraightPlane(Tuple3d linePoint, Vector3d lineDir, Tuple3d planePoint, Vector3d planeNormal, Tuple3d intersectPoint) {
+        intersectPoint.set(planePoint);
+        intersectPoint.sub(linePoint);
+        double u = planeNormal.dot(new Vector3d(intersectPoint));
+        double v = planeNormal.dot(lineDir);
+        if (Math.abs(v) < NEAR_ZERO)
+            return false;
+        u /= v;
+        intersectPoint.set(lineDir);
+        intersectPoint.scale(u);
+        intersectPoint.add(linePoint);
+        return true;
+    }
+    
+    public static boolean intersectStraightPlane(Tuple3d linePoint, Vector3d lineDir, Tuple3d planePoint, Vector3d planeNormal, Vector3d intersectPoint, double[] u) {
+        intersectPoint.set(planePoint);
+        intersectPoint.sub(linePoint);
+        u[0] = planeNormal.dot(intersectPoint);
+        double v = planeNormal.dot(lineDir);
+        if (Math.abs(v) < NEAR_ZERO)
+            return false;
+        u[0] /= v;
+        intersectPoint.set(lineDir);
+        intersectPoint.scale(u[0]);
+        intersectPoint.add(linePoint);
+        return true;
+    }
+    
+    public static boolean intersectLineLine(Tuple3d l1_start,Tuple3d l1_end,Tuple3d l2_start,Tuple3d l2_end,Tuple3d l1_pos, Tuple3d l2_pos) {
+            Vector3d p13 = new Vector3d();
+            Vector3d p43 = new Vector3d();
+            Vector3d p21 = new Vector3d();
+            double d1343,d4321,d1321,d4343,d2121;
+            double numer,denom;
+            p13.sub(l1_start, l2_start);
+            p43.sub(l2_end,l2_start);
+            if (Math.abs(p43.x)  < NEAR_ZERO && Math.abs(p43.y)  < NEAR_ZERO && Math.abs(p43.z)  < NEAR_ZERO)
+               return false;
+            p21.sub(l1_end,l1_start);
+            if (Math.abs(p21.x)  < NEAR_ZERO && Math.abs(p21.y)  < NEAR_ZERO && Math.abs(p21.z)  < NEAR_ZERO)
+               return false;
+
+            d1343 = p13.dot(p43);
+            d4321 = p43.dot(p21);
+            d1321 = p13.dot(p21);
+            d4343 = p43.lengthSquared();
+            d2121 = p21.lengthSquared();
+
+            denom = d2121 * d4343 - d4321 * d4321;
+            if (Math.abs(denom) < NEAR_ZERO)
+               return false;
+            numer = d1343 * d4321 - d1321 * d4343;
+
+            double mua = numer / denom;
+            double mub = (d1343 + d4321 * mua) / d4343;
+ 
+            l1_pos.x = l1_start.x + mua * p21.x;
+            l1_pos.y = l1_start.y + mua * p21.y;
+            l1_pos.z = l1_start.z + mua * p21.z;
+            l2_pos.x = l2_start.x + mub * p43.x;
+            l2_pos.y = l2_start.y + mub * p43.y;
+            l2_pos.z = l2_start.z + mub * p43.z;
+
+            return true;
+    }
+    
+    public static boolean intersectStraightStraight(Tuple3d p1,Vector3d p21,Tuple3d p3,Vector3d p43,Tuple3d pa,Tuple3d pb) {
+        Vector3d p13 = new Vector3d();
+
+        double d1343,d4321,d1321,d4343,d2121;
+        double numer,denom;
+        
+        p13.sub(p1, p3);
+        if (Math.abs(p43.x)  < NEAR_ZERO && Math.abs(p43.y)  < NEAR_ZERO && Math.abs(p43.z)  < NEAR_ZERO)
+           return false;
+        if (Math.abs(p21.x)  < NEAR_ZERO && Math.abs(p21.y)  < NEAR_ZERO && Math.abs(p21.z)  < NEAR_ZERO)
+           return false;
+
+        d1343 = p13.dot(p43);
+        d4321 = p43.dot(p21);
+        d1321 = p13.dot(p21);
+        d4343 = p43.lengthSquared();
+        d2121 = p21.lengthSquared();
+
+        denom = d2121 * d4343 - d4321 * d4321;
+        if (Math.abs(denom) < NEAR_ZERO)
+           return false;
+        numer = d1343 * d4321 - d1321 * d4343;
+
+        double mua = numer / denom;
+        double mub = (d1343 + d4321 * mua) / d4343;
+
+        pa.x = p1.x + mua * p21.x;
+        pa.y = p1.y + mua * p21.y;
+        pa.z = p1.z + mua * p21.z;
+        pb.x = p3.x + mub * p43.x;
+        pb.y = p3.y + mub * p43.y;
+        pb.z = p3.z + mub * p43.z;
+
+        return true;
+   }
+    
+    /**
+     * Calculate the line segment PaPb that is the shortest route between
+     *  two lines P1P2 and P3P4. Calculate also the values of mua and mub where
+     *  Pa = P1 + mua (P2 - P1)
+     *  Pb = P3 + mub (P4 - P3)
+     * @param p1
+     * @param p21
+     * @param p3
+     * @param p43
+     * @param pa
+     * @param pb
+     * @param mu
+     * @return
+     */
+    public static boolean intersectStraightStraight(Tuple3d p1,Vector3d p21,Tuple3d p3,Vector3d p43,Tuple3d pa,Tuple3d pb, double mu[]) {
+        Vector3d p13 = new Vector3d();
+
+        double d1343,d4321,d1321,d4343,d2121;
+        double numer,denom;
+        double EPS = 0.001;
+        p13.sub(p1, p3);
+        if (Math.abs(p43.x)  < EPS && Math.abs(p43.y)  < EPS && Math.abs(p43.z)  < EPS)
+           return false;
+        if (Math.abs(p21.x)  < EPS && Math.abs(p21.y)  < EPS && Math.abs(p21.z)  < EPS)
+           return false;
+
+        d1343 = p13.dot(p43);
+        d4321 = p43.dot(p21);
+        d1321 = p13.dot(p21);
+        d4343 = p43.lengthSquared();
+        d2121 = p21.lengthSquared();
+
+        denom = d2121 * d4343 - d4321 * d4321;
+        if (Math.abs(denom) < EPS)
+           return false;
+        numer = d1343 * d4321 - d1321 * d4343;
+
+        mu[0] = numer / denom;
+        mu[1] = (d1343 + d4321 * mu[0]) / d4343;
+
+        pa.x = p1.x + mu[0] * p21.x;
+        pa.y = p1.y + mu[0] * p21.y;
+        pa.z = p1.z + mu[0] * p21.z;
+        pb.x = p3.x + mu[1] * p43.x;
+        pb.y = p3.y + mu[1] * p43.y;
+        pb.z = p3.z + mu[1] * p43.z;
+
+        return true;
+   }
+   
+  
+   
+   public static void rotate(Quat4d q, Tuple3d in, Tuple3d out) {
+       // p' = q * p * q'
+       double tw =           - q.x*in.x - q.y*in.y - q.z*in.z;
+       double tx =  q.w*in.x            + q.y*in.z - q.z*in.y;
+       double ty =  q.w*in.y - q.x*in.z            + q.z*in.x;
+       double tz =  q.w*in.z + q.x*in.y - q.y*in.x           ;
+       
+       //temp * q' -> x = -x, y = -y z = -z
+       //out.w = tw*q.w + tx*q.x + ty*q.y + tz*q.z;
+       out.x =  -tw*q.x + tx*q.w - ty*q.z + tz*q.y;
+       out.y =  -tw*q.y + tx*q.z + ty*q.w - tz*q.x;
+       out.z =  -tw*q.z - tx*q.y + ty*q.x + tz*q.w;  
+   }
+   
+   public static void getMatrix(Quat4d quat, Matrix3d m) {
+		   m.m00 = 1.0f - 2.0 * (quat.y * quat.y + quat.z * quat.z);
+		   m.m01 = 2.0 * (quat.x * quat.y + quat.w * quat.z);
+		   m.m02 = 2.0 * (quat.x * quat.z - quat.w * quat.y);
+		   m.m10 = 2.0 * (quat.x * quat.y - quat.w * quat.z);
+		   m.m11 = 1.0 - 2.0f * (quat.x * quat.x + quat.z * quat.z);
+		   m.m12 = 2.0 * (quat.y * quat.z + quat.w * quat.x);
+		   m.m20 = 2.0 * (quat.x * quat.z + quat.w * quat.y);
+		   m.m21 = 2.0 * (quat.y * quat.z - quat.w * quat.x);
+		   m.m22 = 1.0 - 2.0f * (quat.x * quat.x + quat.y * quat.y);
+
+   }
+   
+   
+   private static double q[] = new double[3];
+   private static int nxt[] = { 1, 2, 0 };
+   /**
+    * Converts Matrix to Quaternion
+    * 
+    * Note: non-thread safe.
+    * 
+    * @param mat
+    * @param quat
+    */
+   public static void getQuat(Matrix3d mat, Quat4d quat) {
+	   double tr = mat.m00 + mat.m11 + mat.m22;
+		if (tr > 0.0) {
+			double s = Math.sqrt(tr + 1.0);
+			quat.w = 0.5 * s;
+			s = 0.5 / s;
+			quat.x = (mat.m21 - mat.m12) * s;
+			quat.y = (mat.m02 - mat.m20) * s;
+			quat.z = (mat.m10 - mat.m01) * s;
+		} else {
+			int i = 0, j, k;
+			if (mat.m11 > mat.m00)
+				i = 1;
+			if (mat.m22 > mat.getElement(i, i))
+				i = 2;
+			
+
+			j = nxt[i];
+			k = nxt[j];
+
+			double s = Math.sqrt((mat.getElement(i, i) - (mat.getElement(j, j) + mat.getElement(k, k))) + 1.0);
+
+			q[i] = s * 0.5;
+
+			if (Math.abs(s) > 0.001)
+				s = 0.5 / s;
+
+			quat.w = (mat.getElement(k, j) - mat.getElement(j, k)) * s;
+			q[j] = (mat.getElement(j, i) + mat.getElement(i, j)) * s;
+			q[k] = (mat.getElement(k, i) + mat.getElement(i, k)) * s;
+
+			quat.x = q[0];
+			quat.y = q[1];
+			quat.z = q[2];
+		}
+	}
+   
+   public static Quat4d getQuat(Matrix3d mat) {
+	   Quat4d q = new Quat4d();
+	   getQuat(mat, q);
+	   return q;
+   }
+   
+   public static AxisAngle4d getFromPseudoEuler(Vector3d euler) {
+       AxisAngle4d aa = new AxisAngle4d();
+       aa.angle = euler.length();
+       Vector3d normal = new Vector3d(euler);
+       if (aa.angle > NEAR_ZERO) {
+           normal.normalize();
+           aa.x = normal.x;
+           aa.y = normal.y;
+           aa.z = normal.z;
+       } else {
+           aa.x = 1.0;
+           aa.y = 0.0;
+           aa.z = 0.0;
+       }
+       
+       return aa;
+   }
+   
+   public static Vector3d getPseudoEuler(AxisAngle4d aa) {
+       Vector3d euler = new Vector3d(aa.x,aa.y,aa.z);
+       euler.scale(aa.angle);
+       return euler;
+   }
+   
+   
+   public static void getQuat(Vector3d euler, Quat4d quat)  {
+	   Quat4d q = EulerTools.getQuatFromEuler(Order.YXZ, euler.y,euler.x,euler.z);
+	   quat.set(q);
+	// http://en.wikipedia.org/wiki/Rotation_formalisms_in_three_dimensions#Conversion_formulae_between_formalisms
+	// Using the x-convention, the 3-1-3 Euler angles phi, theta and psi (around the Z, X and again the Z-axis)   
+//	   quat.x = -Math.cos((euler.x - euler.z)*0.5)*Math.sin(euler.y*0.5);
+//	   quat.y = -Math.sin((euler.x - euler.z)*0.5)*Math.sin(euler.y*0.5);
+//	   quat.z = -Math.sin((euler.x + euler.z)*0.5)*Math.cos(euler.y*0.5);
+//	   quat.w = Math.sin((euler.x + euler.z)*0.5)*Math.cos(euler.y*0.5);
+	   
+	   // http://www.euclideanspace.com/maths/geometry/rotations/conversions/eulerToQuaternion/index.htm
+	   // Y, Z, X order
+//	    double c1 = Math.cos(euler.y*0.5);
+//	    double s1 = Math.sin(euler.y*0.5);
+//	    double c2 = Math.cos(euler.z*0.5);
+//	    double s2 = Math.sin(euler.z*0.5);
+//	    double c3 = Math.cos(euler.x*0.5);
+//	    double s3 = Math.sin(euler.x*0.5);
+//	    double c1c2 = c1*c2;
+//	    double s1s2 = s1*s2;
+//	    quat.w =c1c2*c3 - s1s2*s3;
+//	    quat.x =c1c2*s3 + s1s2*c3;
+//	    quat.y =s1*c2*c3 + c1*s2*s3;
+//	    quat.z =c1*s2*c3 - s1*c2*s3;
+
+//	    Quat4d q2 = EulerTools.getQuatFromEuler(Order.YZX, euler.y,euler.z,euler.x);
+//	    System.out.println("Q " + quat + " Q2 " + q2);
+//	   double c1 = Math.cos(euler.y);
+//	    double s1 = Math.sin(euler.y);
+//	    double c2 = Math.cos(euler.z);
+//	    double s2 = Math.sin(euler.z);
+//	    double c3 = Math.cos(euler.x);
+//	    double s3 = Math.sin(euler.x);
+//	    quat.w = Math.sqrt(1.0 + c1 * c2 + c1*c3 - s1 * s2 * s3 + c2*c3) / 2.0;
+//	    double w4 = (4.0 * quat.w);
+//	    quat.x = (c2 * s3 + c1 * s3 + s1 * s2 * c3) / w4 ;
+//	    quat.y = (s1 * c2 + s1 * c3 + c1 * s2 * s3) / w4 ;
+//	    quat.z = (-s1 * s3 + c1 * s2 * c3 +s2) / w4 ;
+   }
+   
+   
+  
+   
+   public static void getEuler(Quat4d quat,Vector3d euler)  {
+	   Vector3d e = EulerTools.getEulerFromQuat(Order.YXZ, quat);
+	   euler.x = e.y;
+	   euler.y = e.x;
+	   euler.z = e.z;
+	   
+	   // http://en.wikipedia.org/wiki/Rotation_formalisms_in_three_dimensions#Conversion_formulae_between_formalisms
+//	   euler.x = Math.atan2(quat.x * quat.z + quat.y* quat.w, quat.y*quat.z - quat.x * quat.w);
+//	   euler.y = Math.acos(-square(quat.x) - square(quat.y) + square(quat.z) + square(quat.w));
+//	   euler.z = -Math.atan2(quat.x * quat.z - quat.y* quat.w, quat.y*quat.z + quat.x * quat.w);
+	   
+	   // http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToEuler/index.htm
+	  // Y, Z, X order
+//	   double test = quat.x * quat.y + quat.z * quat.w;
+//	   if (test > NEAR_HALF) {
+//		   euler.y = 2.0 * Math.atan2(quat.x,quat.w);
+//		   euler.z = Math.PI * 0.5;
+//		   euler.x = 0.0;
+//	   } else if (test < -NEAR_HALF) {
+//		   euler.y = -2.0 * Math.atan2(quat.x,quat.w);
+//		   euler.z = -Math.PI * 0.5;
+//		   euler.x = 0.0;
+//	   } else {
+//		   double sqx = square(quat.x);
+//		   double sqy = square(quat.y);
+//		   double sqz = square(quat.z);
+//		   euler.y = Math.atan2(2.0*(quat.y*quat.w-quat.x*quat.z), 1.0 - 2.0*(sqy-sqz));
+//		   euler.z = Math.asin(2.0*test);
+//		   euler.x = Math.atan2(2.0*(quat.x*quat.w-quat.y*quat.z), 1.0 - 2.0*(sqx-sqz));
+//		   System.out.println(euler + " " + EulerTools.getEulerFromQuat(Order.YXZ, quat) +  " " + quat);
+//	   }
+//	   double sqw = quat.w*quat.w;
+//	    double sqx = quat.x*quat.x;
+//	    double sqy = quat.y*quat.y;
+//	    double sqz = quat.z*quat.z;
+//		double unit = sqx + sqy + sqz + sqw; // if normalised is one, otherwise is correction factor
+//		double test = quat.x*quat.y + quat.z*quat.w;
+//		if (test > 0.499*unit) { // singularity at north pole
+//			euler.y = 2 * Math.atan2(quat.x,quat.w);
+//			euler.z = Math.PI/2;
+//			euler.x = 0;
+//			return;
+//		}
+//		if (test < -0.499*unit) { // singularity at south pole
+//			euler.y = -2 * Math.atan2(quat.x,quat.w);
+//			euler.z = -Math.PI/2;
+//			euler.x = 0;
+//			return;
+//		}
+//		euler.y = Math.atan2(2*quat.y*quat.w-2*quat.x*quat.z , sqx - sqy - sqz + sqw);
+//		euler.z = Math.asin(2*test/unit);
+//		euler.x = Math.atan2(2*quat.x*quat.w-2*quat.y*quat.z , -sqx + sqy - sqz + sqw);
+   }
+   
+   public static Quat4d getQuat(Vector3d euler) {
+	   Quat4d q = new Quat4d();
+	   getQuat(euler,q);
+	   return q;
+   }
+   
+   
+   public static Vector3d getEuler(Quat4d quat) {
+	   Vector3d v = new Vector3d();
+	   getEuler(quat, v);
+	   return v;
+   }
+   
+   public static Quat4d getQuat(AxisAngle4d aa) {
+	   Quat4d q = new Quat4d();
+	   getQuat(aa, q);
+	   return q;
+   }
+   
+   public static AxisAngle4d getAxisAngle(Quat4d q) {
+	   AxisAngle4d aa = new AxisAngle4d();
+	   aa.set(q);
+	   return aa;
+   }
+   
+   public static Quat4d getIdentityQuat() {
+	   return new Quat4d(0, 0, 0, 1);
+   }
+   
+   public static void getQuat(AxisAngle4d aa, Quat4d q) {
+	   double mag,amag;
+		// Quat = cos(theta/2) + sin(theta/2)(roation_axis) 
+		
+		amag = Math.sqrt( aa.x*aa.x + aa.y*aa.y + aa.z*aa.z);
+		if( amag < NEAR_ZERO ) {
+		    q.w = 1.0;
+		    q.x = 0.0;
+		    q.y = 0.0;
+		    q.z = 0.0;
+		} else {  
+		   amag = 1.0/amag; 
+		   double a2 = aa.angle * 0.5;
+		   mag = Math.sin(a2);
+		   q.w = Math.cos(a2);
+	       q.x = aa.x*amag*mag;
+	       q.y = aa.y*amag*mag;
+	       q.z = aa.z*amag*mag;
+		}
+   }
+   
+   
+	/*
+	 * Cohen-Sutherland
+	 */
+	
+	private static final int IN = 0;
+	private static final int LEFT = 1;
+	private static final int RIGHT = 2;
+	private static final int BOTTOM = 4;
+	private static final int TOP = 8;
+	
+	
+	private static int bitcode(Vector2f p1, Vector2f min, Vector2f max) {
+		int code = IN;
+		if (p1.x < min.x)
+			code |= LEFT;
+		else if (p1.x > max.x)
+			code |= RIGHT;
+		if (p1.y < min.y)
+			code |= BOTTOM;
+		else if (p1.y > max.y)
+			code |= TOP;
+		return code;
+	}
+	
+	public static boolean clipLineRectangle(Vector2f p1,Vector2f p2, Vector2f min, Vector2f max, Vector2f r1, Vector2f r2) {
+		while (true) {
+			int o1 = bitcode(p1, min, max);
+			int o2 = bitcode(p2, min, max);
+			int and = o1 & o2;
+			int or = o1 | o2;
+			if (and != IN) {
+				return false;
+			}
+			if (or == IN) {
+				r1.set(p1);
+				r2.set(p2);
+				return true;
+			}
+			if (o1 == IN) {
+				Vector2f t = p1;
+				p1 = p2;
+				p2 = t;
+				int t2 = o1;
+				o1 = o2;
+				o2 = t2;
+			}
+			if ((o1 & TOP) != IN) {
+				float t = (max.y - p1.y) / (p2.y - p1.y);
+				p1.x += t * (p2.x - p1.x);
+				p1.y = max.y;
+			} else if ((o1 & BOTTOM) != IN) {
+				float t = (min.y - p1.y) / (p2.y - p1.y);
+				p1.x += t * (p2.x - p1.x);
+				p1.y = min.y;
+			} else if ((o1 & LEFT) != IN) {
+				float t = (min.x - p1.x) / (p2.x - p1.x);
+				p1.y += t * (p2.y - p1.y);
+				p1.x = min.x;
+			} else if ((o1 & RIGHT) != IN) {
+				float t = (max.x - p1.x) / (p2.x - p1.x);
+				p1.y += t * (p2.y - p1.y);
+				p1.x = max.x;
+			} else {
+				throw new RuntimeException("Error in clipping code");
+			}
+		}
+		
+	}
+	
+	public static double square(double d) {
+		return d * d;
+	}
+	
+	
+	 public static void multiplyOrientation(AxisAngle4d aa, AxisAngle4d rot)  {
+		Quat4d q1 = new Quat4d();
+		getQuat(aa, q1);
+		Quat4d q2 = new Quat4d();
+		getQuat(rot, q2);
+		q2.mul(q1);
+		rot.set(q2);
+	 }
+	 
+	 public static double radToDeg(double rad) {
+		 return (rad / Math.PI) * 180.0;
+	 }
+	 
+	 public static double degToRad(double deg) {
+		 return (deg / 180.0) * Math.PI;
+	 }
+	 
+	 public static double clamp(double min, double max,double v) {
+		 if (v < min)
+			 return min;
+		 if (v > max)
+			 return max;
+		 return v;
+	 }
+	 
+	 public static AxisAngle4d createRotation(Vector3d original, Vector3d rotated) { 
+		AxisAngle4d result = new AxisAngle4d();
+		if (createRotation(original, rotated, result))
+			return result;
+		return null;
+	 }
+	 
+	 
+	 public static void setIdentity(Quat4d q) {
+		q.w = 1.0;
+		q.x = 0.0;
+		q.y = 0.0;
+		q.z = 0.0;
+	 }
+	 
+	public static void setIdentity(AxisAngle4d aa) {
+		aa.angle = 0.0;
+		aa.x = 0.0;
+		aa.y = 1.0;
+		aa.z = 0.0;
+	}
+	
+	public static void set(Matrix3d mat, double m00, double m01, double m02,
+			double m10, double m11, double m12, double m20, double m21,
+			double m22) {
+		mat.m00 = m00;
+		mat.m01 = m01;
+		mat.m02 = m02;
+
+		mat.m10 = m10;
+		mat.m11 = m11;
+		mat.m12 = m12;
+
+		mat.m20 = m20;
+		mat.m21 = m21;
+		mat.m22 = m22;
+	}
+	
+	public static void set(Matrix4d mat, double[] v) {
+		mat.m00 = v[0];
+		mat.m01 = v[1];
+		mat.m02 = v[2];
+		mat.m03 = v[3];
+
+		mat.m10 = v[4];
+		mat.m11 = v[5];
+		mat.m12 = v[6];
+		mat.m13 = v[7];
+
+		mat.m20 = v[8];
+		mat.m21 = v[9];
+		mat.m22 = v[10];
+		mat.m23 = v[11];
+
+		mat.m30 = v[12];
+		mat.m31 = v[13];
+		mat.m32 = v[14];
+		mat.m33 = v[15];
+
+	}
+	 
+	 public static boolean createRotation(Vector3d original, Vector3d rotated, AxisAngle4d result) {
+		 
+			if (rotated.lengthSquared() > 0.01)
+				rotated.normalize();
+			else
+				return false;
+			double d = original.dot(rotated);
+			if (d > 0.9999) {
+				// original and rotated are parallel, pointing at the same direction
+				result.angle = 0.0;
+				result.x = 0.0;
+				result.y = 1.0;
+				result.z = 0.0;
+			} else if (d < -0.9999) {
+				// original and rotated are parallel, pointing at the opposite direction 
+				Vector3d a = Z_AXIS;
+				if (Math.abs(a.dot(original)) > 0.8 )
+					a = Y_AXIS;
+				result.set(a, Math.PI);
+			} else {
+				double angle = original.angle(rotated);
+				Vector3d axis = new Vector3d();
+				axis.cross(original, rotated);
+				result.set(axis,angle);
+			}
+			return true;
+		 }
+	 
+	 public static boolean createRotation(Vector3d original, Vector3d rotated, Quat4d result) {
+		 
+			if (rotated.lengthSquared() > 0.01)
+				rotated.normalize();
+			else
+				return false;
+			double d = original.dot(rotated);
+			if (d > 0.9999) {
+				// original and rotated are parallel, pointing at the same direction
+				result.w = 1.0;
+				result.x = 0.0;
+				result.y = 0.0;
+				result.z = 0.0;
+			} else if (d < -0.9999) {
+				// original and rotated are parallel, pointing at the opposite direction 
+				Vector3d a = Z_AXIS;
+				if (Math.abs(a.dot(original)) > 0.8 )
+					a = Y_AXIS;
+				getQuat(a, Math.PI, result);
+				
+			} else {
+				double angle = original.angle(rotated);
+				Vector3d axis = new Vector3d();
+				axis.cross(original, rotated);
+				getQuat(axis, angle, result);
+			}
+			return true;
+		 }
+	 
+	 public static void getQuat(Vector3d axis, double angle, Quat4d q)
+    {
+		double mag,amag;
+		// Quat = cos(theta/2) + sin(theta/2)(roation_axis) 
+		
+		amag = Math.sqrt( axis.x*axis.x + axis.y*axis.y + axis.z*axis.z);
+		if( amag < EPS ) {
+		    q.w = 1.0;
+		    q.x = 0.0;
+		    q.y = 0.0;
+		    q.z = 0.0;
+		} else {  
+		    amag = 1.0/amag; 
+		    double a2 = angle*0.5;
+		    mag = Math.sin(a2);
+		    q.w = Math.cos(a2);
+		    q.x = axis.x*amag*mag;
+		    q.y = axis.y*amag*mag;
+		    q.z = axis.z*amag*mag;
+		}
+	
+    }
+	 
+	 /**
+	  * Linear interpolation of quaternions. Result IS set to q1.
+	  * @param q1
+	  * @param q2
+	  * @param alpha
+	  */
+	 public static void lip(Quat4d q1, Quat4d q2, double alpha) {
+		 double s1 = 1.0 - alpha;
+		 double s2 = alpha;
+		 q1.scale(s1);
+		 mad(q1,q2,s2);
+		 q1.normalize();
+	 }
+	 
+	 public static double dot(Quat4d q1, Quat4d q2) {
+		 return q1.x * q2.x + q1.y * q2.y + q1.z * q2.z + q1.w * q2.w;
+	 }
+	 
+	 public static void mad(Tuple3d q1, Tuple3d q2, double s2) {
+		 q1.x += q2.x * s2;
+		 q1.y += q2.y * s2;
+		 q1.z += q2.z * s2;
+	 }
+	 
+	 public static void mad(Quat4d q1, Quat4d q2, double s2) {
+		 q1.x += q2.x * s2;
+		 q1.y += q2.y * s2;
+		 q1.z += q2.z * s2;
+		 q1.w += q2.w * s2;
+	 }
+	 
+	 /**
+	  * Slerp
+	  * 
+	  * Sets results to q1. Modifies q2.
+	  * 
+	  * @param q1
+	  * @param q2
+	  * @param alpha
+	  */
+	 public static void sip(Quat4d q1, Quat4d q2, double alpha) {
+		 double cosom = dot(q1,q2);
+		 if (cosom < 0.0) {
+			 cosom = -cosom;
+			 q2.negate();
+		 }
+		 
+		 if (cosom > 0.9999) {
+			 q2.sub(q1);
+			 q2.scale(alpha);
+			 q1.add(q2);
+			 q1.normalize();
+			 return;
+		 }
+		 double theta_0 = Math.acos(cosom);
+		 double theta = theta_0 * alpha;
+		 Quat4d t = new Quat4d(q1);
+		 t.scale(-cosom);
+		 t.add(q2);
+		 t.normalize();
+		 t.scale(Math.sin(theta));
+		 q1.scale(Math.cos(theta));
+		 q1.add(t);
+	 }
+}