Drawing A2xA2 Dynkin diagram with dynkin-diagrams

diagrams

This is a follow up question: How do I draw it exactly as in the blackboard picture I provide, that is with ellipses around the nodes and for the bottom one with the connections to the rightmost node straight not curved.

I posted it as a comment first but I am not sure people notice when comments are added. Thanks a lot.

Edit: here is minimal working example

\documentclass[12pt]{amsbook}

\usepackage{dynkin-diagrams}

\begin{document}
 
 Question: how do I produced a diagram which only keeps the square in this diagram 
 \dynkin[fold] A{*****}? I.e. a Satake-Tits diagram of type A2xA2 but I do not want to have just \dynkin A2 \dynkin A2 but have the nodes paired up. 

\end{document}

I am using the excellent package Dynkin-diagram .sty
and drawing the diagrams for the non-split version of the Freudenthal-Tits magic square.
I managed to draw all but one of them. In picture below the bottom one
can easily be drawn with

\dynkin[fold] A{*****}

My question is how do I draw the top one? Thanks a lot

enter image description here

Addition: Benjamin Kindly offered to include FTMS non-split into his package. The others I managed to draw, here the output as well as latex code which produces it

enter image description here

\documentclass[12pt]{amsbook}
\usepackage[dvipsnames,table]{xcolor}
\usepackage{dynkin-diagrams}


\begin{document}
 
\begin{center}
\Large
\begin{tabular}{| c | c | c | c | c |}\hline
\cellcolor{lightgray!90} $\mathbb{A}\setminus \mathbb{B}$ &  \cellcolor{lightgray!90} $\mathbb{K}$  & \cellcolor{lightgray!90} $\mathbb{L}$   & \cellcolor{lightgray!90} $\mathbb{H}$ & \cellcolor{lightgray!90} $\mathbb{O}$  \\ \hline
\cellcolor{lightgray!90} $\mathbb{K}$ &  \cellcolor{BurntOrange!80} \dynkin A1  & \cellcolor{BurntOrange!80}  \dynkin A{*o}   & \cellcolor{BurntOrange!80} \dynkin C{o*o} & \cellcolor{BurntOrange!80} \dynkin F{*ooo}  \\ \hline
\cellcolor{lightgray!90} $\mathbb{L}$ &  \cellcolor{SeaGreen} \dynkin A{**}  & \cellcolor{SeaGreen} \begin{dynkinDiagram}[name=upper]A2
\node (current) at ($(upper root 1)+(0,-.35cm)$) {};
\dynkin[at=(current),name=lower]A2
\begin{pgfonlayer}{Dynkin behind}
\foreach \i in {1,2}{%
\draw[/Dynkin diagram/fold style] ($(upper root \i)$) -- ($(lower root \i)$);}
\end{pgfonlayer}
\end{dynkinDiagram}& \cellcolor{SeaGreen} \dynkin A{*ooo*} & \cellcolor{SeaGreen} \dynkin E{*oooo*}\\ \hline
\cellcolor{lightgray!90} $\mathbb{H}$  &  \cellcolor{RoyalBlue!50} \dynkin C{***}  & \cellcolor{RoyalBlue!50} \dynkin[fold] A{*****} & \cellcolor{RoyalBlue!50} \dynkin D{*oo*o*} & \cellcolor{RoyalBlue!50} \dynkin E{*oooo**}\\ \hline
\cellcolor{lightgray!90} $\mathbb{O}$ &  \cellcolor{OrangeRed!70} \dynkin F{****}  &  \cellcolor{OrangeRed!70} \begin{dynkinDiagram}[mark=o]E{II} \dynkinRootMark{*}1
\dynkinRootMark{*}3 \dynkinRootMark{*}5 \dynkinRootMark{*}6 \dynkinRootMark{*}2 \dynkinRootMark{*}4 \end{dynkinDiagram}

& \cellcolor{OrangeRed!70} \dynkin[backwards] E{*o**oo*o} & \cellcolor{Red} ${\color{white} \dynkin E{*oooo***}}$\\ \hline
\end{tabular}
\end{center}

\end{document}

Also here are the diagrams as made in Keynote, they are drawn to emphasize the residual property, namely taking a point residue (covering a dot if you are unfamiliar with buildings language) in a picture yields the one above when going from row 4 to 3, row 3 to 2 (row 2 to 1 is different and uses folding)

enter image description here

Best Answer

Connecting diagrams is described in ยง28 of the Dynkin Diagrams Package documentation.

enter image description here

You can adjust the vertical space between upper and lower by changing the -.3cm in the code below:

\documentclass[12pt]{amsbook}

\usepackage{dynkin-diagrams}

\begin{document}

Is this:
\begin{dynkinDiagram}[name=upper]A2
\node (current) at ($(upper root 1)+(0,-.3cm)$) {};
\dynkin[at=(current),name=lower]A2
\begin{pgfonlayer}{Dynkin behind}
\foreach \i in {1,2}{%
\draw[/Dynkin diagram/fold style] ($(upper root \i)$) -- ($(lower root \i)$);}
\end{pgfonlayer}
\end{dynkinDiagram}
what you want?

\end{document}
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