private void AddHead() { Vector3 newheadvelocity; if (elementList.Count > 0) // set old head element color. { var oldeadelement = elementList[elementList.Count - 1]; oldeadelement.Color = color; newheadvelocity = objectToFollow.Velocity; } else { newheadvelocity = Vector3.Zero; } // add new white head element. var newelement = new BillboardChain.Element(); newelement.Position = objectToFollow.OldPosition; newelement.Width = maxwidth; newelement.Color = ColorEx.White; Chain.AddChainElement(0, newelement); elementList.Add(newelement); elementPositions.Add(new Ray(newelement.Position, newheadvelocity)); }