%Calculate p-(unit)vector: store in (q)
%Parameters: #1:t
\newcommand{\CalcQ}[1]
{
   \pgfmathparse{deg(#1)} \let\Angle\pgfmathresult
   \pgfmathparse{sin(\Angle)} \let\x\pgfmathresult
   \pgfmathparse{cos(\Angle)} \let\y\pgfmathresult
   \coordinate (q) at (\x,\y);
}
%Calculate p-(unit)vector : store in (p)
%Parameters: #1:t
\newcommand{\CalcP}[1]
{
   \pgfmathparse{deg(#1)} \let\Angle\pgfmathresult
   \pgfmathparse{cos(\Angle)} \let\x\pgfmathresult
   \pgfmathparse{-sin(\Angle)} \let\y\pgfmathresult
   \coordinate (p) at (\x,\y);
}

