填充路径但同时只绘制其中的一部分

Question

我想填充角扇区，并在一个命令中绘制其曲线部分。我尝试使用移动到命令，但它不起作用。

\documentclass[tikz,10pt]{standalone}
\usetikzlibrary{calc}

\pgfkeys{/tikz/.cd,
  MarkAngleDim/.store in=\MarkAngleDim,
  MarkAngleDim=0.5,
  MarkDim/.store in=\MarkDim,
  MarkDim=2,
   }

\newcommand{\MarkAngle}[3][]{%
    \foreach \Bn/\An/\Cn in {#2} {%
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{\Bn}{center}}%
        \global\let\AnglA\pgfmathresult ;
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{\Cn}{center}}%
        \global\let\AnglB\pgfmathresult ;   
        \pgfmathparse{ifthenelse(\AnglA>\AnglB,\AnglA-360,\AnglA)}          \global\let\AnglA\pgfmathresult ;   

%################# the faulty path #####################
    \path[very thin,#1] (\An) to[move to]
        ($(\An) !\MarkAngleDim cm!(\Bn)$)
        arc (\AnglA:\AnglB:\MarkAngleDim)
                    node[pos=.5] (Angle\Bn\An\Cn) {}
        to[move to] (\An) --cycle;
%#######################################################

        \ifnum#3>0
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{Angle\Bn\An\Cn}{center}}%
        \global\let\AnglC\pgfmathresult ;

        \begin{scope}[shift={(\An)}]
        \foreach \i [evaluate=\i as \ang
                    using \AnglC+2*(\i-#3/2-.5)/\MarkAngleDim]
        in {1,...,#3} {%
        \draw[very thin] (\ang:\MarkAngleDim cm +\MarkDim pt)
                        --(\ang:\MarkAngleDim cm -\MarkDim pt) ;
        }
        \end{scope}
        \fi
    }
    }


\begin{document}
\begin{tikzpicture}

\coordinate (A) at (0,0) ;
\coordinate (B) at (1,1) ;
\coordinate (C) at (0,-1) ;

\MarkAngle[draw,blue,fill=red!25]{C/A/B}{2} ;

\draw[dashed] (B)--(A)--(C) ;

\node[label=135:A] at (A) {} ;
\node[label=B] at (B) {} ;
\node[label=270:C] at (C) {} ;

\end{tikzpicture}

\end{document}

Answer 1

\documentclass[tikz,10pt]{standalone}
\usetikzlibrary{calc}

\pgfkeys{/tikz/.cd,
  MarkAngleDim/.store in=\MarkAngleDim,
  MarkAngleDim=0.5,
  MarkDim/.store in=\MarkDim,
  MarkDim=2,
   }

\newcommand{\MarkAngle}[3][]{%
    \foreach \Bn/\An/\Cn in {#2} {%
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{\Bn}{center}}%
        \global\let\AnglA\pgfmathresult ;
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{\Cn}{center}}%
        \global\let\AnglB\pgfmathresult ;   
        \pgfmathparse{ifthenelse(\AnglA>\AnglB,\AnglA-360,\AnglA)}          \global\let\AnglA\pgfmathresult ;   

%################# the faulty path #####################
    \path[draw opacity=0,#1] ($(\An) !\MarkAngleDim cm!(\Bn)$) -- (\An) --
        ($(\An) !\MarkAngleDim cm!(\Cn)$);
    \path[very thin,#1] ($(\An) !\MarkAngleDim cm!(\Bn)$)
        arc (\AnglA:\AnglB:\MarkAngleDim)
        node[pos=.5] (Angle\Bn\An\Cn) {};
%#######################################################

        \ifnum#3>0
        \pgfmathanglebetweenpoints%
        {\pgfpointanchor{\An}{center}}%
        {\pgfpointanchor{Angle\Bn\An\Cn}{center}}%
        \global\let\AnglC\pgfmathresult ;

        \begin{scope}[shift={(\An)}]
        \foreach \i [evaluate=\i as \ang
                    using \AnglC+2*(\i-#3/2-.5)/\MarkAngleDim]
        in {1,...,#3} {%
        \draw[very thin] (\ang:\MarkAngleDim cm +\MarkDim pt)
                        --(\ang:\MarkAngleDim cm -\MarkDim pt) ;
        }
        \end{scope}
        \fi
    }
    }

\begin{document}
\begin{tikzpicture}

\coordinate (A) at (0,0) ;
\coordinate (B) at (1,1) ;
\coordinate (C) at (0,-1) ;

\MarkAngle[draw,blue,fill=red!25]{C/A/B}{2} ;

\draw[dashed] (B)--(A)--(C) ;

\node[label=135:A] at (A) {} ;
\node[label=B] at (B) {} ;
\node[label=270:C] at (C) {} ;

\end{tikzpicture}

\end{document}