我正在画一个带有 ti 的 DNA 符号图像钾頁面：
我使用以下方法完成此操作decorations.markings：
\documentclass[margin = 12mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations.markings}
\begin{document}\begin{tikzpicture}
\newcommand*{\adenin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = red]%
\fill(0, -.1) -- (.35, -.1) -- (.45, 0) -- (.35, .1) -- (0, .1) -- cycle;%
\end{scope}}%
\newcommand*{\thymin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = blue]%
\fill(0, -.1) -- (.35, -.1) -- (.25, 0) -- (.35, .1) -- (0, .1) -- cycle;
\end{scope}}%
\newcommand*{\guanin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = green]%
\fill(0, -.1) -- (.35, -.1) arc(-90:90:.1) -- (.35, .1) -- (0, .1) -- cycle;% -- (0, .1) -- cycle;%
\end{scope}}%
\newcommand*{\cytosin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = yellow]%
\fill(0, -.1) -- (.35, -.1) arc(270:90:.1) -- (.35, .1) -- (0, .1) -- cycle;%
\end{scope}}%
\draw[double distance = 1pt, line cap = rect, decoration = {
markings,
mark = at position 5pt with { \adenin{(0, 0)}{270} },
% 200 more lines with at position ...
mark = at position 370pt with { \cytosin{(0, 0)}{270}{1.25} }
}, preaction = {decorate}, shorten <= -3pt]
(-.5, -1.2) .. controls (2, 1) and (4, -1) .. (6, 0)
.. controls (9, 1.5) and (10, 0) .. (12, 0);
% the other three paths with each 200 lines with at position...
\end{tikzpicture}\end{document}
根据钾z 手册，31.5 标记只能使用以下任一方式指定
/pgf/decoration/mark=at position <pos> with <code>
哪里<pos>一数字或
/pgf/decoration/mark=between positions <start pos> and <end pos> step <stepping> with <code>
这个只是为了定期重复的标记，但事实并非如此。
因为看起来没有办法指定标记位置的列表，所以我认为最简单的方法是对每个位置进行循环，但我不知道如何将循环放在选项定义中。
虽然这不会改变任何结果，但我对如何简化我的代码很感兴趣。抱歉，示例太长了。提前感谢你的帮助
答案1
我会做些稍微不同的事情。我会将哪种蛋白质应该位于列表中的哪个位置的信息存储起来，并指示标记使用此列表。我添加了一个命令\somein，它接受一个参数，根据参数是否为、、或，\adenin{(0, 0)}{270}扩展为 \thymin{(0, 0)}{270}、、或。（也可以编写一个命令，接受蛋白质的名称或等等。）然后有一个列表，指示哪种蛋白质应该位于位置 1、2 等。\guanin{(0, 0)}{270}\cytosin{(0, 0)}{270}1234AB
\documentclass[margin = 12mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations.markings}
\begin{document}\begin{tikzpicture}
\newcommand*{\adenin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = red]%
\fill(0, -.1) -- (.35, -.1) -- (.45, 0) -- (.35, .1) -- (0, .1) -- cycle;%
\end{scope}}%
\newcommand*{\thymin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = blue]%
\fill(0, -.1) -- (.35, -.1) -- (.25, 0) -- (.35, .1) -- (0, .1) -- cycle;
\end{scope}}%
\newcommand*{\guanin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = green]%
\fill(0, -.1) -- (.35, -.1) arc(-90:90:.1) -- (.35, .1) -- (0, .1) -- cycle;% -- (0, .1) -- cycle;%
\end{scope}}%
\newcommand*{\cytosin}[2]{\begin{scope}[shift = {#1}, rotate = #2, fill = yellow]%
\fill(0, -.1) -- (.35, -.1) arc(270:90:.1) -- (.35, .1) -- (0, .1) -- cycle;%
\end{scope}}%
\newcommand*{\somein}[1]{\ifcase#1
\or
\adenin{(0, 0)}{270}
\or
\thymin{(0, 0)}{270}
\or
\guanin{(0, 0)}{270}
\or
\cytosin{(0, 0)}{270}
\fi
}
\newcommand\myinlst{3, 1, 2, 2, 2, 2, 1, 3, 1, 4, 2, 2, 1, 1, 3, 4, 1,
2, 4, 4, 4, 4, 4, 4, 2, 2, 3, 1, 3, 4, 1, 4, 1, 4,
2, 3, 2, 4, 3, 4, 2, 3, 3, 2, 2, 3, 2, 1, 3, 1, 2,
3, 4, 3, 2, 4, 1, 2, 4, 4, 3, 3, 1, 1, 1, 4, 3, 4,
2, 2, 1, 2, 2, 2, 2, 2, 1, 4, 4, 1, 3, 4, 1, 1, 1,
3, 1, 2, 3, 3, 4, 2, 4, 3, 3, 3, 4, 2, 3, 2}
\draw[double distance = 1pt, line cap = rect, decoration = {
markings,
mark=between positions 5pt and 0.99 step 10pt
with
{\pgfmathtruncatemacro{\myin}{{\myinlst}[\pgfkeysvalueof{/pgf/decoration/mark info/sequence number}-1]}
\somein{\myin}},
% 200 more lines with at position ...
}, preaction = {decorate}, shorten <= -3pt]
(-.5, -1.2) .. controls (2, 1) and (4, -1) .. (6, 0)
.. controls (9, 1.5) and (10, 0) .. (12, 0);
% the other three paths with each 200 lines with at position...
\end{tikzpicture}
\end{document}
答案2
感谢 AndréC 的评论，我使用列表解决了这个问题：
\begin{document}\begin{tikzpicture}[
adenin/.style = {decoration = {markings,
mark = at position #1 with { \adenin{(0, 0)}{270} }
}}, thymin/.style = {decoration = {markings,
mark = at position #1 with { \thymin{(0, 0)}{270} }
}}, guanin/.style = {decoration = {markings,
mark = at position #1 with { \guanin{(0, 0)}{270} }
}}, cytosin/.style = {decoration = {markings,
mark = at position #1 with { \cytosin{(0, 0)}{270} }
}}]
对于每个核苷酸，然后将它们称为：
\draw[double distance = 1pt, line cap = rect,
thymin/.list = {5pt, 15pt, 35pt},
adenin/.list = {25pt, 45pt, 55pt},
guanin/.list = {75pt, 85pt, 115pt},
cytosin/.list = {65pt, 95pt, 105pt},
preaction = {decorate}, shorten <= -3pt]
(-.5, -1.2) .. controls (2, 1) and (4, -1) .. (6, 0)
然而，这违反了必须沿路径放置标记的原则：
然而，在使用多个标记的情况下，路径上的位置必须按升序排列。（pgf 手册第 384 页）。
因此，标记的位置非常奇怪：
