当我使用以下代码时，图形似乎被切割了，就像从一个太紧的边界框中切割出来一样。
\documentclass{article}
\usepackage{pgf}
\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{shapes,arrows}
\usetikzlibrary{calc}
\usetikzlibrary{external}
\tikzexternalize
\usetikzlibrary{positioning}
\tikzstyle{seed}=[-latex,red, thick]
\tikzstyle{ray}=[green!50!black,dotted,thick,-latex]
\begin{document}
\newcommand{\door}[1] {
\begin{scope}[shift={#1}]
\draw[red] (-0.5,0) arc (180:270:1cm);
\draw[black] (0.5,-1) -- (0.5,-0) node[right, near start]{};
\draw[black,dotted] (-0.5,0) -- (0.5,-0)node(doorstepcenter)[pos=0.5]{} ;
\end{scope}
}
\newcommand{\room}{
\coordinate (a1) at (4.5,0.5);
\coordinate (a2) at (4.5,4);
\coordinate (a3) at (0,4);
\coordinate (a4) at (1,3);
\coordinate (a5) at (1.4,3) ;
\coordinate (a6) at (1.4,2.6) ;
\coordinate (a7) at (1,2.6) ;
\coordinate (a8) at (1,3);
\coordinate (a9) at (0,4);
\coordinate (a10) at (0,0.5) ;
\coordinate (a11) at (4.5,0.5);
}
\begin{tikzpicture}%[node distance =4.5cm,thick]
\room; %just get the door
\door{ ($ (a10)!0.5! (a1) -(0,0.1) $) };
\coordinate (r1) at (a6);
\coordinate (r2) at (a7);
\coordinate (ray) at ($ (r1)!.3!(r2) $);
\draw[ray] (doorstepcenter.center) -- (ray) node [below=10pt, midway]{ray};
\path (a1)--(a2) node[pos=0.5,left,text width = 3cm, text centered]{Polygon cannot be closed };
\draw[seed] (r1) -- (r2);
\draw[thick] (a4) -- (a5);
\draw[thick] (a5) -- (a6);
\draw[seed] (a7) -- (a8);
\draw[seed] (a8) -- (a9);
\draw[seed] (a9) -- (a10);
\draw[seed] (a10) -- (a11);
\draw[seed] (a11) -- (a2);
\draw[seed] (a2) -- (a3);
\end{tikzpicture}
\end{document}
左右箭头似乎被切断了。这是怎么回事？如何避免？
答案1
发生这种情况是因为您正在使用external库（顺便说一句，您应该更清楚地说明这一点），该库会生成图片的 PDF 图像并将其包含在内，以减少进一步编译器运行的编译时间（图片仅处理一次）。箭头不被视为官方路径的一部分，因此 PGF/TikZ 不会扩展官方边界框来保存它们。相反，它将大小限制为行。也许这个问题将在 PGF/TikZ 的未来版本中得到修复，或者也许有原因导致它没有完成。
您忘记了\tikzexternalize示例代码前言中的宏。没有这个宏，就不会进行外部化，因此您的图片不会被剪切。这就是为什么其他用户一开始可能会重现您的问题的原因。虽然在这种情况下边界框仍然相同，但箭头只是从框中向外看，但仍会显示。
解决这个问题的一种方法是稍微扩展边界框。我找不到可以实现这一点的边距或边框选项external。您可以通过在图片末尾添加使用特殊current bounding box节点的虚拟路径来自己完成此操作。可能还有另一种更好的方法。
\documentclass{article}
\usepackage{pgf}
\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{shapes,arrows}
\usetikzlibrary{calc}
\usetikzlibrary{external}
\usetikzlibrary{positioning}
\tikzstyle{seed}=[-latex,red, thick]
\tikzstyle{ray}=[green!50!black,dotted,thick,-latex]
\tikzexternalize
\begin{document}
\newcommand{\door}[1] {
\begin{scope}[shift={#1}]
\draw[red] (-0.5,0) arc (180:270:1cm);
\draw[black] (0.5,-1) -- (0.5,-0) node[right, near start]{};
\draw[black,dotted] (-0.5,0) -- (0.5,-0)node(doorstepcenter)[pos=0.5]{} ;
\end{scope}
}
\newcommand{\room}{
\coordinate (a1) at (4.5,0.5);
\coordinate (a2) at (4.5,4);
\coordinate (a3) at (0,4);
\coordinate (a4) at (1,3);
\coordinate (a5) at (1.4,3) ;
\coordinate (a6) at (1.4,2.6) ;
\coordinate (a7) at (1,2.6) ;
\coordinate (a8) at (1,3);
\coordinate (a9) at (0,4);
\coordinate (a10) at (0,0.5) ;
\coordinate (a11) at (4.5,0.5);
}
\begin{tikzpicture}%[node distance =4.5cm,thick]
\room; %just get the door
\door{ ($ (a10)!0.5! (a1) -(0,0.1) $) };
\coordinate (r1) at (a6);
\coordinate (r2) at (a7);
\coordinate (ray) at ($ (r1)!.3!(r2) $);
\draw[ray] (doorstepcenter.center) -- (ray) node [below=10pt, midway]{ray};
\path (a1)--(a2) node[pos=0.5,left,text width = 3cm, text centered]{Polygon cannot be closed };
\draw[seed] (r1) -- (r2);
\draw[thick] (a4) -- (a5);
\draw[thick] (a5) -- (a6);
\draw[seed] (a7) -- (a8);
\draw[seed] (a8) -- (a9);
\draw[seed] (a9) -- (a10);
\draw[seed] (a10) -- (a11);
\draw[seed] (a11) -- (a2);
\draw[seed] (a2) -- (a3);
\path
([shift={(-5\pgflinewidth,-5\pgflinewidth)}]current bounding box.south west)
([shift={( 5\pgflinewidth, 5\pgflinewidth)}]current bounding box.north east);
\end{tikzpicture}
\end{document}
请注意，类和包external是的替代方案。类提供了一个选项，为您增加了一些余地。这看起来如下所示，并且还需要aka编译器选项。standalonestandaloneborder-shell-escape--enabled-write18
% Main document
\documentclass{article}
\usepackage[subpreambles,mode=buildnew]{standalone}
\begin{document}
\includestandalone{mytikzpic} % or \input, but here you can use [<options>]
\end{document}
\documentclass[border=1pt]{standalone}
\usepackage{pgf}
\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{shapes,arrows}
\usetikzlibrary{calc}
\usetikzlibrary{positioning}
\tikzstyle{seed}=[-latex,red, thick]
\tikzstyle{ray}=[green!50!black,dotted,thick,-latex]
\begin{document}
\newcommand{\door}[1] {
\begin{scope}[shift={#1}]
\draw[red] (-0.5,0) arc (180:270:1cm);
\draw[black] (0.5,-1) -- (0.5,-0) node[right, near start]{};
\draw[black,dotted] (-0.5,0) -- (0.5,-0)node(doorstepcenter)[pos=0.5]{} ;
\end{scope}
}
\newcommand{\room}{
\coordinate (a1) at (4.5,0.5);
\coordinate (a2) at (4.5,4);
\coordinate (a3) at (0,4);
\coordinate (a4) at (1,3);
\coordinate (a5) at (1.4,3) ;
\coordinate (a6) at (1.4,2.6) ;
\coordinate (a7) at (1,2.6) ;
\coordinate (a8) at (1,3);
\coordinate (a9) at (0,4);
\coordinate (a10) at (0,0.5) ;
\coordinate (a11) at (4.5,0.5);
}
\begin{tikzpicture}%[node distance =4.5cm,thick]
\room; %just get the door
\door{ ($ (a10)!0.5! (a1) -(0,0.1) $) };
\coordinate (r1) at (a6);
\coordinate (r2) at (a7);
\coordinate (ray) at ($ (r1)!.3!(r2) $);
\draw[ray] (doorstepcenter.center) -- (ray) node [below=10pt, midway]{ray};
\path (a1)--(a2) node[pos=0.5,left,text width = 3cm, text centered]{Polygon cannot be closed };
\draw[seed] (r1) -- (r2);
\draw[thick] (a4) -- (a5);
\draw[thick] (a5) -- (a6);
\draw[seed] (a7) -- (a8);
\draw[seed] (a8) -- (a9);
\draw[seed] (a9) -- (a10);
\draw[seed] (a10) -- (a11);
\draw[seed] (a11) -- (a2);
\draw[seed] (a2) -- (a3);
\path
([shift={(-5\pgflinewidth,-5\pgflinewidth)}]current bounding box.south west)
([shift={( 5\pgflinewidth, 5\pgflinewidth)}]current bounding box.north east);
\end{tikzpicture}
\end{document}