TikZ 中的自定义 T 形

Question

我想要定义一个新的“T”形（即下图中的红色和绿色形状），以便我可以使用 TikZ 绘制下图。

不幸的是我不知道该怎么做。说实话，我读过 PGF 手册中的“声明新形状”一节，但我对低级 pgf 命令完全一头雾水。

我该怎么办？欢迎就任何方向提出建议。

Answer 1

最后，我成功地通过改编网络上现有的示例创建了一个“T”形。以下是定义该形状的 pgf 代码。

\makeatletter
\pgfdeclareshape{t}{
    \inheritsavedanchors[from=rectangle]
    \inheritanchorborder[from=rectangle]
    \inheritanchor[from=rectangle]{center}
    \inheritanchor[from=rectangle]{base}
    \inheritanchor[from=rectangle]{north}
    \inheritanchor[from=rectangle]{north east}
    \inheritanchor[from=rectangle]{east}
    \inheritanchor[from=rectangle]{south east}
    \inheritanchor[from=rectangle]{south}
    \inheritanchor[from=rectangle]{south west}
    \inheritanchor[from=rectangle]{west}
    \inheritanchor[from=rectangle]{north west}
    \backgroundpath{
        % store lower right in xa/ya and upper right in xb/yb
       \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
       \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
       \pgfmathparse{(\pgf@xb-\pgf@xa)/2}
       \pgf@xc=\pgf@xa
       \advance\pgf@xc by \pgfmathresult pt
       \pgfpathmoveto{\pgfpoint{\pgf@xa}{\pgf@ya}}
       \pgfpathmoveto{\pgfpoint{\pgf@xa}{\pgf@yb}}
       \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@yb}}
       \pgfpathmoveto{\pgfpoint{\pgf@xc}{\pgf@yb}}
       \pgfpathlineto{\pgfpoint{\pgf@xc}{\pgf@ya}}
   }
}
\makeatother