Spline di Beziér e riempimento in TikZ

Ciao a tutti,

se compilate questo codice:
`\documentclass[a4paper,11pt,extrafontsizes,twoside,openright]{memoir}

\usepackage{etex}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[italian]{babel}
\usepackage{microtype}

\usepackage{xcolor}
\usepackage{tikz}
\usetikzlibrary{arrows}
\usetikzlibrary{backgrounds}
\usetikzlibrary{calc}
\usetikzlibrary{decorations.pathmorphing}
\usetikzlibrary{decorations.markings}
\usetikzlibrary{intersections}
\usetikzlibrary{positioning}
\usetikzlibrary{shadows}
\usetikzlibrary{shapes}
\usetikzlibrary{through}

\def\myFm{*1cm}

\begin{document}

\begin{figure}[tb]
\centering
\begin{tikzpicture}
%riempimento
\pgfpathmoveto{\pgfpoint{4.38568\myFm}{3.87882\myFm}}
\pgfpathcurveto{\pgfpoint{4.39205\myFm}{3.76561\myFm}}{\pgfpoint{4.3888\myFm}{3.65207\myFm}}{\pgfpoint{4.37598\myFm}{3.53941\myFm}}
\pgfpathcurveto{\pgfpoint{4.3606\myFm}{3.40423\myFm}}{\pgfpoint{4.3315\myFm}{3.27096\myFm}}{\pgfpoint{4.2887\myFm}{3.14181\myFm}}
\pgfpathcurveto{\pgfpoint{4.24992\myFm}{3.02478\myFm}}{\pgfpoint{4.2001\myFm}{2.91179\myFm}}{\pgfpoint{4.14324\myFm}{2.8024\myFm}}
\pgfpathcurveto{\pgfpoint{4.07281\myFm}{2.6669\myFm}}{\pgfpoint{3.99175\myFm}{2.53719\myFm}}{\pgfpoint{3.90081\myFm}{2.4145\myFm}}
\fill [gray!50] — (3.90081\myFm,3.87882\myFm);

\fill [gray!50] (3.11378\myFm,2.87028\myFm) — (3.90081\myFm,2.4145\myFm) |- (3.3853\myFm,3.87882\myFm);

\pgfpathmoveto{\pgfpoint{3.3853\myFm}{3.87882\myFm}}
\pgfpathcurveto{\pgfpoint{3.41376\myFm}{3.72195\myFm}}{\pgfpoint{3.41704\myFm}{3.56154\myFm}}{\pgfpoint{3.395\myFm}{3.40364\myFm}}
\pgfpathcurveto{\pgfpoint{3.3729\myFm}{3.24528\myFm}}{\pgfpoint{3.32436\myFm}{3.08891\myFm}}{\pgfpoint{3.22045\myFm}{2.96726\myFm}}
\pgfpathcurveto{\pgfpoint{3.18911\myFm}{2.93057\myFm}}{\pgfpoint{3.15327\myFm}{2.89799\myFm}}{\pgfpoint{3.11378\myFm}{2.87028\myFm}}
\fill [white] — (3.11378\myFm,3.87882\myFm);
\pgfusepath{draw}

%tracciamento “bordo”
\pgfpathmoveto{\pgfpoint{4.38568\myFm}{3.87882\myFm}}
\pgfpathcurveto{\pgfpoint{4.39205\myFm}{3.76561\myFm}}{\pgfpoint{4.3888\myFm}{3.65207\myFm}}{\pgfpoint{4.37598\myFm}{3.53941\myFm}}
\pgfpathcurveto{\pgfpoint{4.3606\myFm}{3.40423\myFm}}{\pgfpoint{4.3315\myFm}{3.27096\myFm}}{\pgfpoint{4.2887\myFm}{3.14181\myFm}}
\pgfpathcurveto{\pgfpoint{4.24992\myFm}{3.02478\myFm}}{\pgfpoint{4.2001\myFm}{2.91179\myFm}}{\pgfpoint{4.14324\myFm}{2.8024\myFm}}
\pgfpathcurveto{\pgfpoint{4.07281\myFm}{2.6669\myFm}}{\pgfpoint{3.99175\myFm}{2.53719\myFm}}{\pgfpoint{3.90081\myFm}{2.4145\myFm}}

\pgfpathmoveto{\pgfpoint{3.11378\myFm}{2.87028\myFm}}
\pgfpathlineto{\pgfpoint{3.90081\myFm}{2.4145\myFm}}

\pgfpathmoveto{\pgfpoint{3.3853\myFm}{3.87882\myFm}}
\pgfpathcurveto{\pgfpoint{3.41376\myFm}{3.72195\myFm}}{\pgfpoint{3.41704\myFm}{3.56154\myFm}}{\pgfpoint{3.395\myFm}{3.40364\myFm}}
\pgfpathcurveto{\pgfpoint{3.3729\myFm}{3.24528\myFm}}{\pgfpoint{3.32436\myFm}{3.08891\myFm}}{\pgfpoint{3.22045\myFm}{2.96726\myFm}}
\pgfpathcurveto{\pgfpoint{3.18911\myFm}{2.93057\myFm}}{\pgfpoint{3.15327\myFm}{2.89799\myFm}}{\pgfpoint{3.11378\myFm}{2.87028\myFm}}
\pgfusepath{draw}
\end{tikzpicture}
\label{fig:esempio}
\caption{Esempio.}
\end{figure}

\end{document}`
otterrete un disegno che è una parte di questo.

Riguardo a ciò che ho fatto, avrei tre domande da porre:

1. La mia idea è quella di realizzare quella parte, ripeterla e specchiarla. C’è un approccio migliore?
2. È possibile specchiare un certo disegno rispetto a un asse?
3. Se ingrandite il disegno ottenuto con il codice, vedrete che i segmenti che costituiscono il “bordo” non sono uniti al meglio. Come posso fare in modo che le tre parti del “bordo” vengano raccordate correttamente?

Grazie mille e buona giornata,
Marco.