How to keep section heading on the same page as a floating image in a landscape layout without getting kicked to the next page?

Question

I need to set up a landscape layout (preferably an environment) for one page in conjuncture with an image scaled to the page's width, and there must be a chapter heading always sitting on the same place. Problem is: The chapter heading can't stay put; it either goes off to the next page or its starting position isn't consistent (it has to).

Another small issue: Maybe it's because of the landscape environment, but the image doesn't scale properly (sometimes). Hence why I tried minipages (but the results aren't very consistent...)

\documentclass{memoir}
\usepackage{geometry}
\usepackage{xcolor}
\usepackage{pagecolor}
\usepackage{pdflscape}

\usepackage{graphicx}
\usepackage{float}
\begin{document}
\newpagecolor{black}
\thispagestyle{empty}
\newgeometry{left=0cm,right=0cm,bottom=0cm,top=0cm}
\begin{landscape}
    \begin{figure}
    \centering
        \begin{minipage}{1\paperheight}
        \includegraphics[keepaspectratio,width=1\textwidth,height=\textheight]{example-image}
        \caption{caption here}
        \end{minipage}
        \begin{minipage}{1\textheight}
        \color{white}\chapter{chapter here}
        \end{minipage}
    \end{figure}
\end{landscape}
\restoregeometry

\end{document}

Here is what the code looks like:

If I remove minipage it would become like this:

What I want is this (intended end result):

EDIT:

I tried using Tikzpicture's positioning feature Positioning relative to page in TikZ to stack a text node but since it is also considered to be a float it still got back down to the next page, sigh.

My next bet is trying to overlay the heading text Tikzpicture's by overlaying upon the whole page (Tikz: overlay png or pdf image over another pdf figure), not sure if it'll work though.

Answer 1

To avoid the "gross hack" you can redefine the memoir class hook \clearforchapter. By default this just clears the page at the start of \chapter, but it can do anything, for example include the graphic.

I also used the memoir \legend command which can put a pseudo-caption anywhere in the document (though it won't appear in any "contents" section like "list of figures" unless you explicitly add a contents line).

\begin{document}
\newpagecolor{black}
\thispagestyle{empty}
\newgeometry{left=0cm,right=0cm,bottom=0cm,top=0cm}
\begin{landscape}
  \renewcommand{\clearforchapter}{%
    \openany % or \openleft or \openright
    \centering
    \includegraphics[width=\linewidth,
    height=.9\textheight % just needed here, as example-image fills the whole page
    ]{example-image}
    \color{white}
    \legend{CAPTION HERE}
    \vspace{-0.3\textheight} % adjust as required to overlap the chapter with the image
  }
\chapter{chapter here}
\end{landscape}
\restoregeometry

\newpagecolor{white}
\chapter{Another chapter here}

\end{document}

Answer 2

If I understand correctly you want something like

You certainly never want a chapter heading inside a float, so I removed that, I also removed the minipage around the image which wasn't doing much. I left one around the chapter heading, just to stop it stating a new page (which is a gross hack but still...)

\documentclass{memoir}
\usepackage{geometry}
\usepackage{xcolor}
\usepackage{pagecolor}
\usepackage{pdflscape}
\usepackage{capt-of}
\usepackage{graphicx}
\usepackage{float}
\begin{document}
\newpagecolor{black}
\thispagestyle{empty}
\newgeometry{left=0cm,right=0cm,bottom=0cm,top=0cm}
\begin{landscape}
    \centering
        \includegraphics[width=\linewidth,
  height=.7\textwidth % just needed here as example-image is too tall for the heading
]{example-image}

 \begin{minipage}{\linewidth}% just to stop \chapter starting a page
 \color{white}
 \captionof{figure}{caption here}
\chapter{chapter here}
\end{minipage}
\end{landscape}
\restoregeometry

\end{document}