I want to use Bezier curves to draw a track in TikZ, e.g., a racetrack.
I have the centerline of the track specified with the help of Bezier curves, like this:
\documentclass[11pt]{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}
\draw[dashed,blue] (0,0) .. controls (1,1) and (2,-1) .. (3,0);
\end{tikzpicture}
\end{document}
I now want to draw the boundary of the track which is always a distance d from the centerline.
What is the best way to achieve this?
double, double distance=<width between lines>, line width=<width of each line>
etc. to the existing path.