使用 TikZ 图案填充矩形的问题

Question

我正在尝试将图案条纹背景添加到矩形中，但使用 PDFLatex 生成的 PDF 会产生几个完全黑色的矩形，而不是用图案填充的矩形。以下代码取自问题的答案使用带有变量的仅限形式模式：可能是 TikZ 错误。

TikZ代码：

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{patterns}

\tikzset{
    slope/.code={\edef\slope{#1}},
    slope/.default=0.9, slope
}

\makeatletter

\pgfdeclarepatternformonly{stripes}{\pgfpoint{0cm}{0cm}}{\pgfpoint{1cm}{1cm}}{\pgfpoint{1cm}{1cm}} {
    \foreach \i in {0.1, 0.3,...,0.9} {
        \pgfpathmoveto{\pgfpoint{\i cm}{0cm}}
        \pgfpathlineto{\pgfpoint{1cm}{1cm - \i cm}}
        \pgfpathlineto{\pgfpoint{1cm}{1cm - \i cm+ 0.1cm}}
        \pgfpathlineto{\pgfpoint{\i cm - 0.1cm}{0cm}}
        \pgfpathclose%
        \pgfusepath{fill}
        \pgfpathmoveto{\pgfpoint{0cm}{\i cm}}
        \pgfpathlineto{\pgfpoint{1cm - \i cm}{1cm}}
        \pgfpathlineto{\pgfpoint{1cm - \i cm - 0.1cm}{1cm}}
        \pgfpathlineto{\pgfpoint{0cm}{\i cm + 0.1cm}}
        \pgfpathclose%
        \pgfusepath{fill}
    }
}

\pgfdeclarepatternformonly[\tikz@pattern@color,\slope]{slant lines}
    {\pgfpoint{-.1mm/\slope}{-.1mm}}
    {\pgfpoint{1.1mm/\slope}{1.1mm}}
    {\pgfpoint{1mm/\slope}{1mm}}{
        \pgfsetlinewidth{0.4pt}
        \pgfpathmoveto{\pgfpoint{-.1mm/\slope}{-.1mm}}
        \pgfpathlineto{\pgfpoint{1.1mm/\slope}{1.1mm}}
        \pgfsetstrokecolor{\tikz@pattern@color}
        \pgfusepath{stroke}
    }

\makeatother

\begin{document}
\begin{tikzpicture}
    \fill[pattern=stripes, pattern color=red] (0,0) rectangle (5,5);
    \fill[pattern=slant lines, pattern color=blue, slope=0.3] (5,0) rectangle (10,5);
\end{tikzpicture}
\end{document}

结果如下图所示：

我究竟做错了什么？