使用 TikZ/pgfkeys 更改键和值

Question

另一个 TikZ 问题：两个向量都绘制了，但第二个向量产生了错误：

! Dimension too large.
<to be read again> 
              \relax 
l.37   \myvector[text align=center](1,1)
                                    ;
I can't work with sizes bigger than about 19 feet.
Continue and I'll use the largest value I can.

我知道如果向量很小，对齐可能会出现问题。但即使没有文本也会出现错误。

因此我尝试测试一下：

\ifx\mbftex\empty \def\mbfdecoration{} \else \mbfdecoration{postaction={decorate,decoration={text along path,text align/.expand once=\mbftextalign,text=\mbftext,raise=\mbfraise}}}} /fi

像这样使用它：

\centerarct[draw=\mbfcolor,line  width=\mbflinewidth,\mbfdecoration](#2)(20:21:\mbfradius);

但这不起作用。好的，我可以让 centerarc 的两个定义依赖于文本是否为空。但还有其他方法吗？我尝试使用 tikzset 和样式来解决问题，但这也没有用。

\documentclass[10pt]{article}
\usepackage[a4paper,top=1in, bottom=1in, left=1in, right=1in]{geometry}
\usepackage{tikz}
\usetikzlibrary{calc,arrows.meta,bending,decorations.text,positioning}

\def\centerarct[#1](#2)(#3:#4:#5)% Syntax: [draw options] (center) (start angle:end angle:radius)
{ \path[#1] ($(#2)+({#5*cos(-#3+90)},{#5*sin(-#3+90)})$) arc [start angle={-#3+90}, end angle={-#4+90}, radius=#5)]; }

\pgfkeys{
    myvector/.is family,
    myvector,
    radius/.initial=4cm,
    line width/.initial =5mm,
    color/.initial=orange,
    text align/.initial=right,
    text/.initial=,
    raise/.initial=0mm
}

\newcommand\myvectorset[1]{\pgfkeys{myvector,#1}}

\def\myvector[#1](#2){
    \myvectorset{#1,
    radius/.get=\mbfradius,
    line width/.get=\mbflinewidth,
    color/.get=\mbfcolor,
    text align/.get=\mbftextalign,
    text/.get=\mbftext,
    raise/.get=\mbfraise
}
\centerarct[draw=\mbfcolor,line  width=\mbflinewidth,postaction={decorate,decoration={text along path,text align/.expand once=\mbftextalign,text=\mbftext,raise=\mbfraise}}](#2)(20:21:\mbfradius);
}

\begin{document}
 \begin{tikzpicture}
  \myvector[](0,0);
  \myvector[text align=center](1,1);
 \end{tikzpicture}
\end{document}

有没有办法实现类似下面的操作？

\documentclass[10pt]{article}
\usepackage[a4paper,top=1in, bottom=1in, left=1in, right=1in]{geometry}
\usepackage{tikz}
\usetikzlibrary{calc,arrows.meta,bending,decorations.text,positioning}

\begin{document}
 \def\mytext{}
 %\ifx\mytext\empty {\def\mykey{draw=red}} \else {\def\mykey{draw=blue}} \fi % not-solved-1
 \begin{tikzpicture}
  \tikzset{mystyle/.style={draw=red}} works
  %\ifx\mytext\empty {\tikzset{mystyle/.style={draw=red}}} \else {\tikzset{mystyle/.style={draw=blue}}} \fi  % not-solved-2
  %\path[mykey] (0,0) -- (1,1); % part of not-solved-1
  \path[mystyle] (0,0) -- (1,1);
 \end{tikzpicture}
\end{document}

因为它有效：

\begin{document}
 \def\mytext{}
 \begin{tikzpicture}
  \ifx \mytext \empty \def\mytest{red} \else \def\mytest{blue} \fi
  \path[draw=\mytest] (0,0) -- (2,1);
 \end{tikzpicture}
\end{document}

但我需要重新替换密钥和它的值。