En effet, le problème n'existe pas en projection orthographique.
Code : Tout sélectionner
\documentclass{article}
\usepackage{asymptote}
\begin{document}
\begin{asy}
settings.prc=false;
settings.outformat="pdf";
settings.render=4;
usepackage("mathdesign",options="charter");
usepackage("amsmath");
import graph3;
real Xrange=6; real Yrange=5;
int Nx=121; int Ny=101;
pen pa=currentpen;pen ps=lightblue;pen pl=1bp+lightmagenta;
//pen pa=invisible;pen ps=lightblue;pen pl=1bp+red;
//pen pa=currentpen;pen ps=invisible;pen pl=invisible;
//real[][] f=input("data/S1.dat").line().dimension(0,0);
triple f(pair t) {
// int i=round(t.x); int j=round(t.y);
// return (i*Xrange/(Nx-1),j*Yrange/(Ny-1),f[i][j]);
return (t.x,t.y,1/(1+t.x^2+t.y^2));
}
limits((0,0,0),(Xrange,Yrange,1));
surface s=surface(f,(0,0),(Xrange,Yrange),Nx,Ny,Spline);
size3(6cm,8cm,5cm,IgnoreAspect);
currentprojection=perspective(camera=(18,-10,4),up=(0,0,1),target=(Xrange/2,Yrange/2,0.5));
xaxis3(Label(XZ()*"$x$",position=MidPoint),0,6,pa,OutTicks(XZ()*Label,endlabel=false,Step=1));
yaxis3(Label(YZ()*"$y$",position=MidPoint,align=SE),XEquals(6),0,5,pa,OutTicks(YZ()*Label,Step=1));
zaxis3(Label("$\mathscr{S}_1(x,y)$",align=N),0,1,pa,InTicks(Step=0.5,0.1));
draw(s,ps);
\end{asy}
\begin{asy}
settings.prc=false;
settings.outformat="pdf";
settings.render=4;
usepackage("mathdesign",options="charter");
usepackage("amsmath");
import graph3;
real Xrange=6; real Yrange=5;
int Nx=121; int Ny=101;
//pen pa=currentpen;pen ps=lightblue;pen pl=1bp+lightmagenta;
pen pa=invisible;pen ps=lightblue;pen pl=1bp+red;
//pen pa=currentpen;pen ps=invisible;pen pl=invisible;
//real[][] f=input("data/S1.dat").line().dimension(0,0);
triple f(pair t) {
// int i=round(t.x); int j=round(t.y);
// return (i*Xrange/(Nx-1),j*Yrange/(Ny-1),f[i][j]);
return (t.x,t.y,1/(1+t.x^2+t.y^2));
}
limits((0,0,0),(Xrange,Yrange,1));
surface s=surface(f,(0,0),(Xrange,Yrange),Nx,Ny,Spline);
size3(6cm,8cm,5cm,IgnoreAspect);
currentprojection=perspective(camera=(18,-10,4),up=(0,0,1),target=(Xrange/2,Yrange/2,0.5));
xaxis3(Label(XZ()*"$x$",position=MidPoint),0,6,pa,OutTicks(XZ()*Label,endlabel=false,Step=1));
yaxis3(Label(YZ()*"$y$",position=MidPoint,align=SE),XEquals(6),0,5,pa,OutTicks(YZ()*Label,Step=1));
zaxis3(Label("$\mathscr{S}_1(x,y)$",align=N),0,1,pa,InTicks(Step=0.5,0.1));
draw(s,ps);
\end{asy}
\vspace{-6.9cm}
\hspace{1.6cm}\begin{asy}
settings.prc=false;
settings.outformat="pdf";
settings.render=0;
usepackage("mathdesign",options="charter");
usepackage("amsmath");
import graph3;
real Xrange=6; real Yrange=5;
int Nx=121; int Ny=101;
//pen pa=currentpen;pen ps=lightblue;pen pl=1bp+lightmagenta;
//pen pa=invisible;pen ps=lightblue;pen pl=1bp+red;
pen pa=currentpen;pen ps=invisible;pen pl=invisible;
//real[][] f=input("data/S1.dat").line().dimension(0,0);
triple f(pair t) {
// int i=round(t.x); int j=round(t.y);
// return (i*Xrange/(Nx-1),j*Yrange/(Ny-1),f[i][j]);
return (t.x,t.y,1/(1+t.x^2+t.y^2));
}
limits((0,0,0),(Xrange,Yrange,1));
surface s=surface(f,(0,0),(Xrange,Yrange),Nx,Ny,Spline);
size3(6cm,8cm,5cm,IgnoreAspect);
currentprojection=perspective(camera=(18,-10,4),up=(0,0,1),target=(Xrange/2,Yrange/2,0.5));
xaxis3(Label(XZ()*"$x$",position=MidPoint),0,6,pa,OutTicks(XZ()*Label,endlabel=false,Step=1));
yaxis3(Label(YZ()*"$y$",position=MidPoint,align=SE),XEquals(6),0,5,pa,OutTicks(YZ()*Label,Step=1));
zaxis3(Label("$\mathscr{S}_1(x,y)$",align=N),0,1,pa,InTicks(Step=0.5,0.1));
draw(s,ps);
\end{asy}
\end{document}