Stacking rectangles with unequal dimensions

Question

I am trying to make figures like the following:

I need flexible code that will scale well for more complex figures with many more rectangles (but the minimal example is as above).

This is my beginner's solution using \usetikzlibrary{positioning}:

\begin{tikzpicture}
\node[draw,rectangle,minimum width=7cm,minimum height=1.2cm] (n1) {(1)};
\node[draw,rectangle,minimum width=4cm,minimum height=0.9cm,above=0 of n1.north west,anchor=south west,node distance=0] (n21) {(2,1)};
\node[draw,rectangle,minimum width=3cm,minimum height=0.9cm,right=0 of n21.east,anchor=west,node distance=0] (n22) {(2,2)};
\end{tikzpicture}

Several issues here:

• Separator lines between adjacent rectangles get drawn twice (visible when zooming close)
• I have to take care manually that 4+3=7 so the widths add up. I would prefer a solution where I only indicate the relative position of vertical separators, i.e., 4/7=0.571
• I need to indicate the minimum height for each rectangle on the same line
• The extensive use of positioning keys and anchors makes the code cumbersome

I am aware of Nested rectangles with different widths. However I need the rectangles to be nodes (not paths) because I need to fit text into them.

In the TikZ manual I didn't find any builtin method that would allow me to do exactly this. So I'd be thankful for indications on how to improve this code.

Answer 1

From its abstract:

The bytefield package helps the user create illustrations for network protocol specifications and anything else that utilizes fields of data.

A simple example like yours can be drawn with

\documentclass[border=2mm]{standalone}
\usepackage{bytefield}
\begin{document}
\bytefieldsetup{bitheight=1cm}
\begin{bytefield}[bitwidth=1cm]{7}
\bitbox{4}{(2,1)} & \bitbox{3}{(2,2)} \\\bytefieldsetup{bitheight=1.2cm}%
\wordbox{1}{(1,1)}
\end{bytefield}

\begin{bytefield}[bitwidth=1cm]{7} declares the longest retangle width in bits (7) and the bit width in an optional parameter.

After that every box is declared with \bitbox{box width in bits}{box contents}. A whole line box is declared with \wordbox{lines height}{box contents}.

bitheight fixes every line height, but can be adjusted for every row

A more complex example taken from bytefield documentation

\documentclass[border=2mm]{standalone}
\usepackage{bytefield}
\begin{document}
\begin{bytefield}[bitwidth=1.1em]{32}
\bitheader{0-31} \\
\begin{rightwordgroup}{RTP \\ Header}
\bitbox{2}{V=2} & \bitbox{1}{P} & \bitbox{1}{X}
& \bitbox{4}{CC} & \bitbox{1}{M} & \bitbox{7}{PT}
& \bitbox{16}{sequence number} \\
\bitbox{32}{timestamp}
\end{rightwordgroup} \\
\bitbox{32}{synchronization source (SSRC) identifier} \\
\wordbox[tlr]{1}{contributing source (CSRC) identifiers} \\
\wordbox[blr]{1}{$\cdots$} \\
\begin{rightwordgroup}{RTP \\ Payload}
\wordbox[tlr]{3}{MPEG-4 Visual stream (byte aligned)} \\
\bitbox[blr]{16}{}
& \bitbox{16}{\dots\emph{optional} RTP padding}
\end{rightwordgroup}
\end{bytefield}
\end{document}

Answer 2

Now a TiKZ solution:

I suppose that all rectangles in a row have same height. Every row is declared in a scope with y=row height shifted according lower rows. Every node is defined to fit its bottom left and top right coordinates but only x coordinate changes because bottom left is at y=0 and top right is always at y=1. This way there's no need for minimum width or minimum height definitions. Text inside nodes is drawn with label=center:...

\documentclass[tikz,border=2mm]{standalone}
\usetikzlibrary{fit}

\begin{document}
\begin{tikzpicture}[every fit/.style={inner sep=0pt, outer sep=0pt, draw}]

\begin{scope}[y=1.5cm]
\node [fit={(0,0) (7,1)}, label=center:{(1,1)}] {};
\end{scope}

\begin{scope}[yshift=1.5cm,y=1cm]
\node [fit={(0,0) (4,1)}, label=center:{(2,1)}] {};
\node [fit={(4,0) (7,1)}, label=center:{(2,2)}] {};
\end{scope}

\begin{scope}[yshift=2.5cm,y=0.8cm]
\node [fit={(0,0) (2,1)}, label=center:{(3,1)}] {};
\node [fit={(2,0) (5,1)}, label=center:{(3,2)}] {};
\node [fit={(5,0) (7,1)}, label=center:{(3,3)}] {};
\end{scope}
\end{tikzpicture}
\end{document}