1. A method for deriving barycentric coordinates for a point p within an n-sided polygon, wherein, for a particular coordinate w j, corresponding to a vertex q j, the method embodies a formula which may be expressed as follows: 15 w j = cot &af; ( γ j ) + cot &af; ( δ j ) &LeftDoubleBracketingBar; p - q j &RightDoubleBracketingBar; 2 j and &ggr; j are adjacent angles to the edge pq j at the vertex q j.