\documentclass[a4paper]{article}
% Manuel Luque <MLuque@aol.com>
% Herbert Voss <voss@perce.de>  - 2003/12/20
\usepackage{pstricks}
\usepackage{pst-node}
\usepackage{pst-plot}
\usepackage{pst-grad}
\usepackage{pst-vue3d}

\input random

\definecolor{pelouse}{cmyk}{0.14,0.42,0.56,0}
\definecolor{base}{rgb}{1,0.8,0}
\newpsstyle{surface}{fillstyle=vlines,hatchcolor=marron,%
	hatchwidth=0.2\pslinewidth,hatchsep=1\pslinewidth}
\newpsstyle{sol}{fillstyle=vlines,hatchcolor=lightgray,%
	hatchwidth=0.2\pslinewidth,hatchsep=1\pslinewidth}
\SpecialCoor

\def\fleuve{%
	\FrameThreeD[normaleLatitude=90,normaleLongitude=90,%
		linestyle=none,fillstyle=gradient,%
		gradbegin=blue,gradend=white](0,0,-2.5)(-12,-14)(12,14)
}
\newcommand{\tablier}{%
	\FrameThreeD[normaleLatitude=90,normaleLongitude=90,%
		linestyle=none,fillstyle=gradient,%
		gradbegin=blue,gradend=white](0,0,0)(-\Xcinf,-2)(\Xcinf,2)%
    \multido{\nL=-\Xcinf+0.2}{196}{%
        \LineThreeD[linecolor=lightgray](\nL,-2,0)(\nL,2,0)%
	}%
}
\newcommand\rembardes{%
	\multido{\iY=-2+4}{2}{%
		\LineThreeD[linecolor=red](-\Xcinf,\iY,0.5)(\Xcinf,\iY,0.5)
		\multido{\rX=-\Xcinf+0.4}{98}{%
			\LineThreeD[linecolor=red](\rX,\iY,0)(\rX,\iY,0.5)%
		}%
	}%
}
\newcommand\bases{%
	\multido{\iYpos=-2+4}{2}{%
		\multido{\rXpos=-\Xc+\twoXc}{2}{%
			\parametricplot[fillstyle=solid,fillcolor=base]{0}{360}{%
				/Xabscisse t cos 1.5 mul \rXpos\space add def
				/Zcote -2.5 def
				/Yordonnee t sin 1.5 mul \iYpos\space add def
				tx@3DDict begin
				    formulesTroisD
				    Xi Yi
 				end
			}%
		}%
	}%
}
\newcommand\Berges{%
	\pNodeThreeD(-\Xcinf,-14,-2){B1}
	\pNodeThreeD(-12,-14,-2.5){B2}
	\pNodeThreeD(-\Xcinf,14,-2){B4}
	\pNodeThreeD(-12,14,-2.5){B3}
	\pspolygon[fillstyle=solid,fillcolor=pelouse](B1)(B2)(B3)(B4)
	\pNodeThreeD(\Xcinf,-14,-2){B1}
	\pNodeThreeD(12,-14,-2.5){B2}
	\pNodeThreeD(\Xcinf,14,-2){B4}
	\pNodeThreeD(12,14,-2.5){B3}
	\pspolygon[fillstyle=solid,fillcolor=pelouse](B1)(B2)(B3)(B4)%
}
\pagestyle{empty}

\def\Radius{14}
\def\Xc{6.5}
\newdimen\tempXc
\tempXc=\Xc pt
\multiply\tempXc by 3
\def\Xcinf{\pointless\tempXc}
\newdimen\temptwoXc
\temptwoXc=\Xc pt
\multiply\temptwoXc by 2
\def\twoXc{\pointless\temptwoXc}

\begin{document}

\psset{PHI=40,THETA=-70,Dobs=30,Decran=8}

\begin{pspicture}(-8,-10)(15,10)
\pNodeThreeD(0,0,0){fictif}
\fleuve%
\Berges\bases%
\multido{\iY=-2+4}{2}{%
	\pnode(!
    	/Xc \Xc\space def
		/Radius \Radius\space def
		/radius1 Xc 2 Radius mul add Xc Radius mul Radius dup mul add
		sqrt 2 mul sub def
		/X1 radius1 def
		/Hpile Radius 1 1 Xc 2 mul dup mul 4 Radius dup mul mul div
			sub sqrt sub mul neg def
		X1 radius1){PointInitial}
	\LineThreeD(-\Xcinf,\iY,-2)(-\Xcinf,\iY,0)
	\LineThreeD(\Xcinf,\iY,-2)(\Xcinf,\iY,0)
	\LineThreeD(-19.5,\iY,0)(19.5,\iY,0)
	\LineThreeD(-\Xc,\iY,-2.5)(-\Xc,\iY,0)
	\LineThreeD(\Xc,\iY,0)(\Xc,\iY,-2.5)
	\multido{\nX=-13+13}{3}{%
		\parametricplot{62.336}{117.664}{%
			/Xabscisse t cos Radius mul \nX\space add def
			/Zcote t sin Radius mul Radius sub def
			/Yordonnee \iY\space def
			tx@3DDict begin
			    formulesTroisD
			    Xi Yi
			end
		}
		\parametricplot{0}{360}{%
			/Xabscisse t cos radius1 mul radius1 add Xc sub \nX\space add def
			/Zcote t sin radius1 mul radius1 add neg def
			/Yordonnee \iY\space def
				tx@3DDict begin
				    formulesTroisD
				    Xi Yi
				end
		}
		\parametricplot{0}{360}{%
			/Xabscisse t cos radius1 mul radius1 add neg Xc 2 mul add \nX\space add Xc sub def
			/Zcote t sin radius1 mul radius1 add neg def
			/Yordonnee \iY\space def
			tx@3DDict begin
			    formulesTroisD
			    Xi Yi
			end
		}
		\multido{\i=0+1}{30}{%
			\pnode(!
				/B Radius X1 mul Xc radius1 mul sub neg def
				/A Radius radius1 sub def
				/C X1 X1 mul Radius mul Xc Xc mul radius1 mul sub def
				/Discriminant B B mul A C mul sub sqrt def
				/X2 B neg Discriminant add A div def
				/radius2 X2 X1 sub 2 exp 4 radius1 mul div def
				X2 radius2){fictif1}
			\multido{\nX=-13+13}{3}{%
				\parametricplot{0}{360}{%
					/Xabscisse t cos radius2 mul X2 add Xc sub \nX\space add def
					/Zcote t sin radius2 mul radius2 add neg def
					/Yordonnee \iY\space def
					tx@3DDict begin
			    		formulesTroisD
			    		Xi Yi
					end
				}
				\parametricplot{0}{360}{%
					/Xabscisse t cos radius2 mul X2 add neg Xc 2 mul add Xc sub \nX\space add def
					/Zcote t sin radius2 mul radius2 add neg def
					/Yordonnee \iY\space def
					tx@3DDict begin
					    formulesTroisD
					    Xi Yi
					end
				}%
			}
			\pnode(!
			/X1 X2 def
				/radius1 radius2 def
				X1 radius1){fictif2}
		}
	}%
}
\tablier
\rembardes
\AxesThreeD[linestyle=dashed,arrowsize=0.2](21,16,10)
\end{pspicture}

\end{document}
