\documentclass[a4paper,10pt,french]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{babel}
\usepackage{tikz}
\usepackage[margin=1cm]{geometry}
\begin{document}
\begin{center}
\begin{tikzpicture}
\tikzset{brique/.style={line width=1mm,draw=gray,fill=red!50!black}}
\clip (0,-15) rectangle (15,7);
\foreach \y in {0.3,1.3,...,5}
{
\foreach \x in {-0.5,0.5,1.5,...,15.5}
{
	\filldraw[brique] ({\x-0.5},{\y-0.25}) rectangle +(1,0.5);
	\filldraw[brique] (\x,{\y+0.5-0.25}) rectangle +(1,0.5);
}
}
\fill[gray!20] (0,0) -- (15,0) -- (13,-15) -- (2,-15) -- cycle;
\begin{scope}[shift={(6,-3)}]
\fill[black] (-0.3,0) .. controls (1,1) and (2,1.5) .. (3,0) .. controls (2,-3) and (1,-1) .. (-0.3,0);
\end{scope}

\begin{scope}[shift={(4.75,3)},scale=1.7]
\fill[black,opacity=0.5] (0,0) .. controls (1,1) and (2,1.5) .. (3,0) .. controls (2,-3) and (1,-1) .. (0,0);
\end{scope}

\draw[dashed] (7.5,-14) -- (9.75,3);
\draw[dashed] (7.5,-14) -- (4.8,3);
\end{tikzpicture}
\end{center}
\end{document}