Hyperref not jumping to the appropriate location for memoir's subbottom

Question

I'm trying to utilize native Memoir subbottom command. However, I'm unable to make hyperref links jump "to the picture", rather than "to the caption". Only links to (a) and (d) work as desired.

\documentclass[a4paper,14pt]{memoir}
\usepackage{graphicx}
\usepackage{hyperref}
% \usepackage[all]{hypcap}

\newsubfloat{figure} % allows to use "subbottom"

\begin{document}
This link jumps to the figure caption: \ref{fig:1}. 
% This one could be fixed with "\usepackage[all]{hypcap}", 
% but is it the correct approach?

This link jumps to the picture (the way I like): \ref{sf:1}. 

This link jumps to slightly-above-subcaption: \ref{sf:2}. 

This link jumps to slightly-above-subcaption: \subcaptionref{sf:3}, same as \ref{sf:3}.

This link jumps to the picture (the way I like): \ref{sf:4}.

This link jumps to slightly-above-subcaption: \ref{sf:5}.

\begin{figure}
\centering
% \hfill   % if uncommented, link to sf:1 jumps to incorrect vertical position too. Why?
\subbottom[Subfigure 1\label{sf:1}]{\includegraphics[width=3cm]{example-image-a}}
\hfill
\subbottom[Subfigure 2\label{sf:2}]{\includegraphics[width=3cm]{example-image-b}}
\hfill
\subbottom[\label{sf:3}Subfigure 3]{\includegraphics[width=3cm]{example-image-c}}
\\
\subbottom[Subfigure 4\label{sf:4}]{\includegraphics[width=3cm]{example-image-b}}
\hfill
\subbottom[\label{sf:5}Subfigure 5]{\includegraphics[width=3cm]{example-image-a}}
\caption{Figure with five subfigures\label{fig:1}}
\end{figure}        


\clearpage
This text is here to add more space for scrolling.

\end{document}

Here's the result I see (TexLive 2018, Windows 10):

My example is similar to those provided in the docs (Figure 10.19 in version v3.7g, 2018/04/04). And it looks like the issue is present in the docs pdf itself.

Similar code, utilizing subcaptionbox works OK. And "Where do hyperlinks jump?" is nicely documented in the subcaption package docs. But it looks like using subcaptionbox with Memoir is discouraged - the following warning is generated:

You are using the caption package with the memoir class. To prepare we will now reset all captioning macros and configurations to kernel defaults, and then let the caption package take over. Please remember to use the caption package interfaces in order to configure your captions.

• Am I doing something wrong?

• Is there any other way to make links jump "to the picture", rather than using caption and subcaption packages?

Answer 1

Here is a more proper patch that does the right thing (move the refstepcoounter) into the formatting. It has been tested with \subbottom, \contsubbottom, \subtop and \contsubtop and the anchors seem to do the right thing

[sub optimal version removed]

---

Edit

This one seems simpler. We add the step counter at the start of the \vtop, this puts the anchor a little higher than the contents, which looks better. And it works with and without hyperref, the earlier version did not. I'll have a look at \subcaption as well.

\usepackage{xpatch}

\makeatletter
% less typing     
\newcommand\mem@step@subcounter{%
  \refstepcounter{sub\@captype}\@contkeep%
}

\xpatchcmd{\@memsubbody}%
{\refstepcounter{sub\@captype}\@contkeep}% search pattern
{}% replacement
{\typeout{@memsubbody is patched}}%
{\typeout{@memsubbody is NOT patched}}%

\xpatchcmd{\@memcontsubbody}%
{\refstepcounter{sub\@captype}\@contkeep}% pattern
{}% replacement
{\typeout{@memcontsubbody is patched}}%
{\typeout{@memcontsubbody is NOT patched}}%

\xpatchcmd{\@memsubfloat}%
{\vtop\bgroup}% search pattern
{\vbox\bgroup\mem@step@subcounter}% replacement
{\typeout{@memsubfloat patch is ok}}%
{\typeout{@memsubfloat patch is NOT ok}}%


\makeatother

---

For \subcaption

\xpatchcmd{\subcaption}%
{\refstepcounter{sub\@captype}}% search pattern
{\H@refstepcounter{sub\@captype}}% replacement
{\typeout{subcaption second patch is ok}}%
{\typeout{subcaption second patch is NOT ok}}%

can be used under hypcap, just note that the link name will be wrong.