Csdrhrt

I want to be able to connect the white rectangles with lines as shown in the picture below (this example consists only of two rectangles, the original code consists of more than 10 of such rectangles). Right now I am working with coordinates. But this is a rather complicated approach and error-prone. It would be ideal if I could define a connecting point by "north-west, south-east" instead of using numeric coordinates. It would also be very helpful if I could additionally connect the lines coming from the left rectangle to the center of the right rectangle.

Is there an easier way to do it? Here is the code and the output it produces:

    documentclass[a5paper]{article}



    usepackage{tikz}

    usetikzlibrary{decorations.pathreplacing}

    usetikzlibrary{fadings}



    usepackage{etoolbox}



    begin{document}



    newcommand{sizein}{1.0}

    newcommand{distin}{0.15}

    newcommand{opacity}{0.8}

    newcommand{xDist}{2.0}



    begin{figure}[htb!]

        centering

        begin{tikzpicture}

            foreach i[count=xi] in {2,...,0}{

                draw [xshift=xDist*0cm, fill=gray, opacity=opacity, draw=black] 

                (distin*i,distin*i) rectangle (distin*i+sizein,distin*i+sizein); 

            }



            foreach i[count=xi] in {2,...,0}{

                draw [xshift=xDist*1cm, fill=gray, opacity=opacity, draw=black] 

                (distin*i,distin*i) rectangle (distin*i+sizein,distin*i+sizein);

            }



            draw [fill=white, draw=black] (0.1,0.1) rectangle (0.3,0.3); 

            draw [fill=white, draw=black] (2.5,0.4) rectangle (2.7,0.6); 



            draw (0.3,0.1) -- (2.7,0.4); 

            draw (0.3,0.3) -- (2.5,0.6); 

    end{tikzpicture}

end{figure}



end{document}

instead of rectangles use nodes with reactangle shape:

documentclass[a5paper]{article}

usepackage{tikz}



begin{document}

newcommand{sizein}{1.0}

newcommand{distin}{0.15}

newcommand{opacity}{0.8}

newcommand{xDist}{2.0}



    begin{tikzpicture}[

box/.style = {draw, fill=gray, opacity=opacity, minimum size=sizein cm},  

wbx/.style = {draw, fill=white, minimum size=distin cm, outer sep=0pt}

                        ]

foreach i in {2,1,0}%

{

    node   [box,above right] at (i*distin,i*distin) {};

    node   [box,above right] at (xDist+i*distin,i*distin) {};

}

node (w1) [wbx] at (0.3,0.3) {};

node (w2) [wbx] at (xDist+0.5,0.5) {};

draw[very thin]   (w1.north west) -- (w2.north west)

        (w1.south east) -- (w2.south east);

    end{tikzpicture}

end{document}            

actual size and position of white boxes you can change according to your needs.