对最底部的子图使用子浮点会破坏对齐

Question

我遇到一个问题，使用子浮点会导致对齐错误。下面是一个代码片段和一个左下角有子浮点和没有子浮点的图。如何在不对代码进行重大更改（即使用完全不同的环境）的情况下修复此问题。

\begin{figure*}
    \centering
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0) {\includegraphics[width=0.22\textwidth]{example-image-a}}; 
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green plate};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = small shelf};
        \end{scope}
    \end{tikzpicture}\\ \vspace{1mm}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
         {\includegraphics[width=0.22\textwidth]{example-image-a}}
         \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}\\ \vspace{1mm}
    \subfloat[]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green cup};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}}
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = small shelf};
        \end{scope}
    \end{tikzpicture}}\\
     \caption{}
     \label{fig:qualitative}
\end{figure*}

编辑：这是 MWE。它使用ieeeconf.cls可以在此处下载http://ras.papercept.net/conferences/support/files/ieeeconf.zip我无法粘贴内容，因为它太大，会导致页面崩溃。

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%        1         2         3         4         5         6         7         8

\documentclass[letterpaper, 10 pt, conference]{ieeeconf}  % Comment this line out if you need a4paper

%\documentclass[a4paper, 10pt, conference]{ieeeconf}      % Use this line for a4 paper

\IEEEoverridecommandlockouts                              % This command is only needed if 
                                                          % you want to use the \thanks command

\overrideIEEEmargins                                      % Needed to meet printer requirements.

% The following packages can be found on http:\\www.ctan.org
\usepackage{amssymb}  % assumes amsmath package installed
\usepackage{amsmath}
\usepackage{booktabs}
\usepackage{tikz}
\usepackage{float}
\usepackage{subfig}

\title{\LARGE \bf
Preparation of Papers for IEEE Sponsored Conferences \& Symposia*
}

\begin{document}

\begin{figure*}
    \centering
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0) {\includegraphics[width=0.22\textwidth]{example-image-a}}; 
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green plate};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = small shelf};
        \end{scope}
    \end{tikzpicture}\\ \vspace{1mm}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}
    \begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
         {\includegraphics[width=0.22\textwidth]{example-image-a}};
         \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}\\ \vspace{1mm}
    \subfloat[$s$ = Set the table for 2 persons \\ $a$ = pick ]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = red cup};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[$s$ = Put all cups on the big shelf \\ $a$ = pick]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = green cup};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[$s$ = Set the table for 3 persons \\ $a$ = place]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = table};
        \end{scope}
    \end{tikzpicture}}
    \subfloat[$s$ = Put jug on small shelf \\ $a$ = place]{\begin{tikzpicture}
        \node[anchor=south west,inner sep=0] (image) at (0,0)
        {\includegraphics[width=0.22\textwidth]{example-image-a}};
        \begin{scope}[x={(image.south east)},y={(image.north west)}]
            \node[scale=0.75,fill=white,thick,draw=red!80] at (0.3,0.1) {$O^{(k)}$ = small shelf};
        \end{scope}
    \end{tikzpicture}}\\
     \caption{}
     \label{fig:qualitative}
\end{figure*}

\end{document}

Answer 1

的代码\subfloat以 结尾（经过几次扩展之后）\ignorespaces，因此其后的空间将被吞噬。如果要保留它，则应添加例如一个空组。

\documentclass{article}

\usepackage{graphicx,subfig}

\begin{document}

\begin{figure}
\centering

% space between pictures
\includegraphics[width=.2\linewidth]{example-image}
\includegraphics[width=.2\linewidth]{example-image}
\caption{}

% space is gobbled away
\subfloat[]{\includegraphics[width=.2\linewidth]{example-image}}
\subfloat[]{\includegraphics[width=.2\linewidth]{example-image}}
\caption{}

% empty group reintroduces space
\subfloat[]{\includegraphics[width=.2\linewidth]{example-image}}{}
\subfloat[]{\includegraphics[width=.2\linewidth]{example-image}}
\caption{}
\end{figure}

\end{document}

Answer 2

您的问题的解决方案是 @campa 在其回答中所说的内容。考虑到这一点，我建议您进行一些额外的更改。

1. 为什么不将subfloat和中的tikzpicture所有项目都包含在同一列中？
2. 使用变量来表示距离。这样，如果您需要更改它们，就不必逐个进行更改。
3. 为节点声明一些样式。与上面相同，您无需重复代码，并且更改起来更容易。
4. （编辑）\strut在标签中添加 s。这可以改善文本的垂直对齐。

像这样：

\documentclass{article}
\usepackage   {lipsum}
\usepackage   {showframe} % just for this example
\usepackage   {subfig}
\usepackage   {tikz}

% styles, to avoid repeating the same code in all the nodes
\tikzset
{%
  image/.style={anchor=south west,inner sep=0},
  label/.style={scale=0.75,fill=white,thick,draw=red!80,anchor=south west}
}

% if you need to change dimensions better not to have to change them one by one, so:
\def\wdt {0.22\textwidth} % width of the figures
\def\vsep{2.2}            % vertical distance between figures
\def\lsep{0.1}            % label distance (you can define differnt x and y distance)

\begin{document}
\lipsum[1]

\begin{figure}[h]
    \centering
    \subfloat[]{% we don't want spaces here
    \begin{tikzpicture}
        \node[image] at (0,0)                 {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep)         {\strut$O^{(k)}$ = green plate};
        \node[image] at (0,-\vsep)            {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-\vsep)   {\strut$O^{(k)}$ = red cup};
        \node[image] at (0,-2*\vsep)          {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-2*\vsep) {\strut$O^{(k)}$ = red cup};
    \end{tikzpicture}}{} % <-- see campa's solution
    \subfloat[]{%
    \begin{tikzpicture}
        \node[image] at (0,0)                 {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep)         {\strut$O^{(k)}$ = green cup};
        \node[image] at (0,-\vsep)            {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-\vsep)   {\strut$O^{(k)}$ = red cup};
        \node[image] at (0,-2*\vsep)          {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-2*\vsep) {\strut$O^{(k)}$ = green cup};
    \end{tikzpicture}}{}
    \subfloat[]{%
    \begin{tikzpicture}
        \node[image] at (0,0)                 {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep)         {\strut$O^{(k)}$ = table};
        \node[image] at (0,-\vsep)            {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-\vsep)   {\strut$O^{(k)}$ = table};
        \node[image] at (0,-2*\vsep)          {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-2*\vsep) {\strut$O^{(k)}$ = table};
    \end{tikzpicture}}{}
    \subfloat[]{%
    \begin{tikzpicture}
        \node[image] at (0,0)                 {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep)         {\strut$O^{(k)}$ = small shelf};
        \node[image] at (0,-\vsep)            {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-\vsep)   {\strut$O^{(k)}$ = table};
        \node[image] at (0,-2*\vsep)          {\includegraphics[width=\wdt]{example-image-a}};
        \node[label] at (\lsep,\lsep-2*\vsep) {\strut$O^{(k)}$ = small shelf};
    \end{tikzpicture}}
    \caption{}
    \label{fig:qualitative}
\end{figure}

\lipsum[2]
\end{document}