Three-columns text with figures of 2\columnwidth

Question

Although in multicol environment (not the twocolumn option in document class) is problematic to place floats, there are some ways to put figures within a single column or occupying the entire width of the text. (That is not the problem)

But how manage figures that must be fitted in 2 columns when there are 3 columns? (ie, images fitted to about 0.65\textwidth after a \begin{multicols}{3}). There are some solution with or without multicol package?

This is a usual design in some books and journals and it is hard to believe that there are no document class, packages nor some clever trick to obtain this. For a single page I suppose that doing some ad hoc manual arrangements, with minipages for example, might be enough, but for a large document this approach would be a torture, so my question is about a general solution.

Answer 1

In case that might be useful for someone, here are a MWE using flowfram as suggested by Stephan Lehmke. Is not comparable to a elegant float of width = n-x columns, but solved the problem.

\documentclass{article}
\usepackage[demo]{graphicx} % Demo for MWE
\usepackage[landscape,margin=1cm]{geometry}
\usepackage{color}
\usepackage{flowfram}
\usepackage{lipsum}
\usepackage{microtype}

\newflowframe[1-7]{0.30\textwidth}{\textheight}
{0pt}{0pt}[leftcolumn]

\newflowframe[2,4-7]{0.30\textwidth}{\textheight}
{0.35\textwidth}{0pt}[centercolumn]

\newflowframe[2,4-7]{0.30\textwidth}{\textheight}
{0.7\textwidth}{0pt}[rightcolumn]

\newflowframe[1,3]{0.30\textwidth}{.6\textheight}
{0.35\textwidth}{0pt}[shortcentercolumn]

\newflowframe[1,3]{0.30\textwidth}{.6\textheight}
{0.7\textwidth}{0pt}[shortrightcolum]

\newstaticframe[1]{0.65\textwidth}{.35\textheight}
{0.35\textwidth}{.65\textheight}[statico]

\newstaticframe[3]{0.65\textwidth}{.35\textheight}
{0.35\textwidth}{.65\textheight}[statico2]

\usepackage{caption}

\title{\textbf{Flowfram demo}}
\author{by Fran}
\date{\today}

\begin{document}

\maketitle

{\color{blue} The dummy text of this MWE flow freely
through three columns in four pages. In pages 1 and 3 the
two landscape images have a width of two columns.}
\bigskip

\lipsum[1]

\begin{figure}[hb]
\includegraphics[width=.3\textwidth]{figure.png}
\caption{This is a float -- here -- figure.}
\end{figure}

\begin{staticcontents*}{statico}
\includegraphics[width=\textwidth, 
 height=0.32\textheight]{figure.png}\\
\captionof{figure}
{This is a non float image in a static frame.}
\end{staticcontents*}

\begin{staticcontents*}{statico2}
\includegraphics[width=\textwidth, 
height=0.32\textheight]{figure.png}\\
\captionof{figure}
{This is another landscape in another static frame.}
\end{staticcontents*}

\lipsum[2-3]

\begin{figure}[h]
\includegraphics[width=.3\textwidth]{figure.png}
\caption{Other float -- here (bottom) -- figure.}
\end{figure}

\lipsum[4-35]

\end{document}