填充 \draw 线和弧之间的区域

Question

我正在尝试在乳胶中填充线条和弧之间的区域。下面是我使用的代码，它没有填满整个区域。我肯定有些地方我做得不对，我是这个平台的新手。有人能帮忙吗？这是我的代码和输出

\begin{tikzpicture}
\draw[name path=A](0.4,0)--(0.2,0)--(0.2,-0.3)--(0.8,-0.5)  (-0.8,-0.5)-- (-0.2,-0.3)--(-0.2,0)--(-0.4,0);
\draw[name path=B](0.8,-0.5)--(0.3,-2)(-0.3,-2)--(-0.8,-0.5)-- (0.8,-0.5);
\draw[name path=C](0.6,-2)++(180:0.3) arc (0:-180:0.3);
%\draw[name path=D](-0.8,-0.5)--(0.8,-0.5);
\begin{pgfonlayer}{bg}
\fill [orange!90,
intersection segments={
    of=A and B,
    sequence={L2--R2}
}];
\fill [orange!90,
intersection segments={
    of=B and C,
    sequence={L2--R2}
}];
\end{pgfonlayer}
\end{tikzpicture}

Answer 1

如果期望的结果是

您可以使用：

\documentclass[margin=5pt]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw
  (0.4,0)--(0.2,0)--(0.2,-0.3)--(0.8,-0.5)
  (-0.8,-0.5)-- (-0.2,-0.3)--(-0.2,0)--(-0.4,0)
;
\draw[fill=orange!90]
  (0.8,-0.5)--(0.3,-2)
  arc (0:-180:0.3)
  --(-0.8,-0.5)--cycle
;
\end{tikzpicture}
\end{document}

Answer 2

A元帖子另一种方法是，通过找到切点，稍微调整一下，使底部的曲线看起来整齐。我相信，你可以使用坐标tangent系在 tikz 中做类似的事情。

\RequirePackage{luatex85}
\documentclass[border=5mm]{standalone}
\usepackage{luamplib}
\begin{document}
\mplibtextextlabel{enable}
\begin{mplibcode}
beginfig(1);
    % set the various points
    z4 = 190 up rotated 25;
    z3 = 200 up rotated 5;
    z2 = z3 shifted 30 up;
    z1 = z2 shifted 20 left;

    % now find the tangent point
    path c, c'; 
    c = fullcircle scaled 50 rotated 90;
    c' = fullcircle scaled abs(z4) shifted 0.5 z4;
    (t,t') = c intersectiontimes c';
    path side, vessel;
    side = z1--z2--z3--z4--subpath(t,4) of c;
    vessel = side & reverse side reflectedabout(up,down);

    level = 3.1;
    fill subpath(0+level,length(vessel)-level) of vessel 
         -- cycle withcolor 1/2[red + 1/2 green, 15/16 white];
    draw vessel withpen pencircle scaled 1;

endfig;
\end{mplibcode}
\end{document}

使用以下方式编译lualatex（或者剥离 LaTeX 包装器并使用mpost）