TikZ：如何向用 pic 语法绘制的圆弧添加箭头？

Question

这个问题继续我的其他。

我的代码：

\documentclass{scrartcl}
\usepackage{stanli}

\usetikzlibrary{
                angles,
                quotes
               }

\begin{document}

  \begin{tikzpicture}

    %the points
    \point{right above}{3}{1.5};
    \point{above}{1}{2};
    \point{below}{0}{0};

    %the hairline
    \draw
      (above) -- (below);

    %the coordinate system
    \draw
      [
       <->,
       dashed
      ] (2.25, 2) node[above] {$x$} -| node[
                                            sloped,
                                            above,
                                            at end
                                           ] {$z$} (1, 0);

    %the arc between the axes (for the pic syntax see page 255 of the TikZ & PGF manual)
    \coordinate (A) at (below);
    \coordinate (B) at (above);
    \coordinate (C) at (1, 0);
    \pic[
         draw,
         angle radius = 10mm,
         angle eccentricity = .75,
         "$\varphi$"
        ] {angle};

    %hinged support
    \support{1}{above}[180];
    \hinge{1}{above};

    %the mass
    \node[
          circle,
          draw,
          fill = white
         ] at (below) {$m$};
  \end{tikzpicture}

\end{document}

生成：

我希望：

我该怎么做？

提前感谢您的努力！

Answer 1

不确定这是否是语法但是有效：

\documentclass{scrartcl}
\usepackage{stanli}

\usetikzlibrary{
                angles,
                quotes
               }

\begin{document}

  \begin{tikzpicture}

    %the points
    \point{right above}{3}{1.5};
    \point{above}{1}{2};
    \point{below}{0}{0};

    %the hairline
    \draw
      (above) -- (below);

    %the coordinate system
    \draw
      [
       <->,
       dashed
      ] (2.25, 2) node[above] {$x$} -| node[
                                            sloped,
                                            above,
                                            at end
                                           ] {$z$} (1, 0);

    %the arc between the axes (for the pic syntax see page 255 of the TikZ & PGF manual)
    \coordinate (A) at (below);
    \coordinate (B) at (above);
    \coordinate (C) at (1, 0);
    \pic[
         draw,<-, %HERE
         angle radius = 10mm,
         angle eccentricity = .75,
         "$\varphi$"
        ] {angle};

    %hinged support
    \support{1}{above}[180];
    \hinge{1}{above};

    %the mass
    \node[
          circle,
          draw,
          fill = white
         ] at (below) {$m$};
  \end{tikzpicture}

\end{document}