Kdtyjb

I've found a Q/A about how to create group nodes to blocks. It works, but exact opposite way as I needed. It defines internals and then draws blocks around them.

I need to define block with internals, LaTeX pseudocode:

begin{tikzpicture}

  myblock(main){Main block name}{

    mynode(anode)[params]

    mynode(bnode)[params,right=of anode]

    myblock(subblock){Subblock name}[below=of anode]{

      mynode(subnodea)[p...]

      mynode(subnodeb)[p...]

    }

  }

  myblock(sideblock){Aux block}[right=of main]{

    ... mynodes ...

  }

end{tikzpicture}

Is there a way, how to define myblock as "complex node" - position is as one node and it moves all its internal nodes.

I've figured out part of the solution (didn't put commands into def yet):

begin{tikzpicture}[

        element/.style={draw=black, fill=white},

        group/.style={draw=black, rounded corners, fill=white}

    ]



    node(main_a)[element]{MAIN A};

    node(group_a)[group, below=of main_a]{

        begin{tikzpicture}

            node(b)[element]{bb};

            node(c)[element, left=of b]{ccc - left};

        end{tikzpicture}

    };

    node(group_a_aux_r)[element,right=of group_a]{Aux Group Right};

    node(group_a_aux_l)[element,left=of group_a]{Aux Group Left};

    node(group_a_aux_b)[element,below=of group_a]{Aux Group Bottom};



    draw[->,red] (main_a) -- (group_a);

    draw[->,red] (group_a) -- (group_a_aux_r);

    draw[->,red] (group_a) -- (group_a_aux_l);

    draw[->,red] (group_a) -- (group_a_aux_b);



    node(group_b)[group, right=of group_a_aux_r]{

        begin{tikzpicture}

            node(d)[element]{dddd};

            node(e)[element, left=of d]{eeee - left};

        end{tikzpicture}

    };



    %code below fails - second image!!

    node(aux_b)[element,right=of b,draw=blue]{Aux B};

    node(aux_c)[element,left=of c,draw=blue]{Aux C};

    draw[->,blue] (b) -- (aux_b);

    draw[->,blue] (c) -- (aux_c);





    draw[->,green] (c) -- (d);

end{tikzpicture}

Here is what I get without inner references:

It works: lays out children, puts it into node and lays it out as node. However, It passes properties of group_a to its children, which is unwanted behaviour!

Here is what I get when inner references are added:

This is completely broken.

Nesting TikZ pictures is not a good idea. It may give strange effects, as it happened to you.

You could use a TikZ matrix instead.

However, it is not clear where you want to position Aux B and Aux C because as they are in your MWE, they overlap with the other nodes.

documentclass{standalone} 

usepackage{tikz}

usetikzlibrary{matrix}

usetikzlibrary{positioning}

begin{document} 

begin{tikzpicture}[

        element/.style={draw=black},

        group/.style={draw=black, rounded corners}

    ]

    node(main_a)[element]{MAIN A};

    matrix[group,

        column sep=3em,

        matrix of nodes,

        nodes={element}, 

        below=of main_a

        ] (group_a) {

            |[name=b]|bb &

            |[name=c]|{ccc - left}\

            };

    node(group_a_aux_r)[element,right= of group_a]{Aux Group Right};

    node(group_a_aux_l)[element,left= of group_a]{Aux Group Left};

    node(group_a_aux_b)[element,below=of group_a]{Aux Group Bottom};

    draw[->,red] (main_a) -- (group_a);

    draw[->,red] (group_a) -- (group_a_aux_r);

    draw[->,red] (group_a) -- (group_a_aux_l);

    draw[->,red] (group_a) -- (group_a_aux_b);

    matrix[group,

        column sep=3em,

        matrix of nodes,

        nodes={element}, 

        right=of group_a_aux_r

        ] (group_b) {

            |[name=d]|dddd &

            |[name=e]|{eeee - left}\

        };

    node(aux_b)[above left= of b,draw=blue]{Aux B};

    node(aux_c)[below right=of c,draw=blue]{Aux C};

    draw[->,blue] (b) -- (aux_b);

    draw[->,blue] (c) -- (aux_c);



    draw[->,green] (c) -- (d);

end{tikzpicture}

end{document}