如何使用奇偶填充规则作为剪辑器或渐变？

Question

我刚刚注意到奇偶填充规则只能用于实心和阴影填充。有时，我需要奇偶规则用于渐变和裁剪。怎么做？我的代码说明了细节。

\documentclass[pstricks,border=12pt]{standalone}
\usepackage{pst-grad}

\newpsstyle{gradient}
{
    fillstyle=gradient,
    gradbegin=red,
    gradend=yellow,
    gradangle=30,
    gradmidpoint=0.5,
}

\newpsstyle{fill}
{
    fillstyle=eofill,
    fillcolor=orange,
}

\def\YinYang#1{%
\begin{pspicture}(-2,-2)(2,2)
    \pscustom[style=#1,dimen=monkey]
    {
        \pscircle(0,0){2}
        \moveto(.25,1)
        \pscircle(0,1){.25}
        \moveto(0,0)
        \psarc(0,-1){1}{90}{270}
        \psarc(0,0){2}{270}{90}
        \psarcn(0,1){1}{90}{270}
        \closepath
        \moveto(.25,-1)
        \pscircle(0,-1){.25}
    }
\end{pspicture}}

\begin{document}
\YinYang{fill}

% there are 2 failed cases:
% 1. with gradient style \YinYang{gradient}
% 2. using the \pscustom of \YingYang as a clipper

\end{document}

笔记

请不要建议我修改路径并使用零填充规则。

编辑

根据下面 Herbert 的回答，以下使用路径作为剪辑器的情况仍然不起作用。

\documentclass[pstricks,border=12pt]{standalone}
\usepackage{graphicx}
\newsavebox\IBox
\savebox\IBox{\includegraphics[scale=2]{example-grid-100x100pt}}

\psset
{
    xunit=.25\wd\IBox,
    yunit=.25\ht\IBox,
}
\begin{document}

\begin{pspicture}(-2,-2)(2,2)
\psclip{%
    \pscustom[dimen=monkey]
    {
        \code{/clip /eoclip load def}
        \pscircle(0,0){2}
        \moveto(.25,1)
        \pscircle(0,1){.25}
        \moveto(0,0)
        \psarc(0,-1){1}{90}{270}
        \psarc(0,0){2}{270}{90}
        \psarcn(0,1){1}{90}{270}
        \closepath
        \moveto(.25,-1)
        \pscircle(0,-1){.25}
    }}
\rput(0,0){\usebox\IBox}
\endpsclip
\end{pspicture}
\end{document}

Answer 1

\def\YinYang#1{%
\begin{pspicture}(-2,-2)(2,2)
    \pscustom[style=#1,dimen=middle]{   
        \code{ /clip /eoclip load def } %%%%%%%%%%%%%
        \pscircle(0,0){2}
        \moveto(.25,1)
        \pscircle(0,1){.25}
        \moveto(0,0)
        \psarc(0,-1){1}{90}{270}
        \psarc(0,0){2}{270}{90}
        \psarcn(0,1){1}{90}{270}
        \closepath
        \moveto(.25,-1)
        \pscircle(0,-1){.25}
    }
\end{pspicture}}

和图片一样：

\begin{pspicture}(-2,-2)(2,2)
\psclip{%
    \pscustom[dimen=middle]
    {
        \code{ /clip /eoclip load def }
        \pscircle(0,0){2}
        \moveto(.25,1)
        \pscircle(0,1){.25}
        \moveto(0,0)
        \psarc(0,-1){1}{90}{270}
        \psarc(0,0){2}{270}{90}
        \psarcn(0,1){1}{90}{270}
        \closepath
        \moveto(.25,-1)
        \pscircle(0,-1){.25}
    }}
\rput(0,0){\usebox\IBox}
\endpsclip
\end{pspicture}