如何增加弯曲区域的厚度？

Question

我可以绘制以下内容：

    \documentclass[11pt]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[x={(170:1cm)},y={(45:1cm)},z={(90:1cm)}]
\coordinate (O) at (-7,-6,0);
\coordinate (R) at (-3.5,-5,4);
\coordinate (A) at (2.5,-2.5,-1);
\coordinate (B) at (2.5,2.5,-1);
\coordinate (C) at (-2.5,2.5,-1);
\coordinate (D) at (-2.5,-2.5,-1);
    \draw[->] (O) --++ (2.5,0,0) node[below] {$X_1$};
    \draw[->] (O) --++ (0,-3,0) node[below] {$X_2$};
    \draw[->] (O) --++ (0,0,2.5) node[right] {$X_3$};

    \filldraw[color=gray!30] 
    (2.5,-2.5,-1)
    to[bend left=25] (2.5,2.5,-1)
    to[bend left=25] coordinate (mp) (-2.5,2.5,-1)
    to[bend right=25] (-2.5,-2.5,-1)
    to[bend right=25] coordinate (mm) (2.5,-2.5,-1)
    -- cycle;
      \draw[very thin] 
    (A)
    to[bend left=25] (B)
    to[bend left=25] coordinate (mp) (C)
    to[bend right=25] (D)
    to[bend right=25] coordinate (mm) (A)
    -- cycle;
\end{tikzpicture}
\end{document}

上述代码的结果是

请问，有人可以帮我修改图片（添加 4 层或更多厚度）如下吗？

Answer 1

在这种情况下，这相当容易，因为你的形状非常好。

更新：带有彩色层。

\documentclass[11pt]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[x={(170:1cm)},y={(45:1cm)},z={(90:1cm)}]
\coordinate (O) at (-7,-6,0);
\coordinate (R) at (-3.5,-5,4);
\coordinate (A) at (2.5,-2.5,-1);
\coordinate (B) at (2.5,2.5,-1);
\coordinate (C) at (-2.5,2.5,-1);
\coordinate (D) at (-2.5,-2.5,-1);
    \draw[->] (O) --++ (2.5,0,0) node[below] {$X_1$};
    \draw[->] (O) --++ (0,-3,0) node[below] {$X_2$};
    \draw[->] (O) --++ (0,0,2.5) node[right] {$X_3$};

\foreach \Z/\Col [count=\X] in {-1.4/blue,-1.3/red,-1.2/green,-1.1/yellow}
{    \filldraw[color=\Col] 
    (-2.5,2.5,-1) --
    (-2.5,2.5,\Z)
    to[bend right=25] ({-2.5-0.05*(5-\X)},{-2.5-0.05*(5-\X)},\Z)
    to[bend right=25] (2.5,-2.5,\Z)
    -- (2.5,-2.5,-1);
}   
    \filldraw[color=gray!30] 
    (2.5,-2.5,-1)
    to[bend left=25] (2.5,2.5,-1)
    to[bend left=25] coordinate (mp) (-2.5,2.5,-1)
    to[bend right=25] (-2.5,-2.5,-1)
    to[bend right=25] coordinate (mm) (2.5,-2.5,-1)
    -- cycle;


      \draw[very thin] 
    (A)
    to[bend left=25] (B)
    to[bend left=25] coordinate (mp) (C)
    to[bend right=25] (D)
    to[bend right=25] coordinate (mm) (A)
    -- cycle;
\end{tikzpicture}
\end{document}

比较一下：使用 tikz-3dplot。不一定更好，但可能更容易改变视角等。

\documentclass[11pt,tikz,border=3.14pt]{standalone}
\usepackage{tikz-3dplot}
\begin{document}
\tdplotsetmaincoords{70}{-20}
\begin{tikzpicture}[tdplot_main_coords]
\coordinate (O) at (-7,-6,0);
\coordinate (R) at (-3.5,-5,4);
\coordinate (A) at (2.5,-2.5,-1);
\coordinate (B) at (2.5,2.5,-1);
\coordinate (C) at (-2.5,2.5,-1);
\coordinate (D) at (-2.5,-2.5,-1);
    \draw[->] (O) --++ (2.5,0,0) node[below] {$X_1$};
    \draw[->] (O) --++ (0,-3,0) node[below] {$X_2$};
    \draw[->] (O) --++ (0,0,2.5) node[right] {$X_3$};

\foreach \Z/\Col [count=\X] in {-1.4/blue,-1.3/red,-1.2/green,-1.1/yellow}
{    \filldraw[color=\Col] 
    (-2.5,2.5,-1) --
    (-2.5,2.5,\Z)
    to[bend left=25] ({-2.5-0.02*(5-\X)},{-2.5-0.02*(5-\X)},\Z)
    to[bend left=25] (2.5,-2.5,\Z)
    -- (2.5,-2.5,-1)  to[bend left=25]  (2.5,2.5,-1)
    -- cycle;
}   
    \filldraw[color=gray!30] 
    (2.5,-2.5,-1)
    to[bend right=25] (2.5,2.5,-1)
    to[bend right=25] coordinate (mp) (-2.5,2.5,-1)
    to[bend left=25] (-2.5,-2.5,-1)
    to[bend left=25] coordinate (mm) (2.5,-2.5,-1)
    -- cycle;


      \draw[very thin] 
    (A)
    to[bend right=25] (B)
    to[bend right=25] coordinate (mp) (C)
    to[bend left=25] (D)
    to[bend left=25] coordinate (mm) (A)
    -- cycle;
\end{tikzpicture}
\end{document}