Drawing polygons

Question

I would like to draw the following picture using TikZ:

I've done this

\documentclass{standalone}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}[scale=2]
    \foreach \x in {0,60,...,300} {
        \draw[fill] (\x:1 cm) -- (\x + 60:1 cm);
        \draw[fill] (\x:1 cm) -- (\x + 180:1 cm);}
    \foreach \x in {30,90,...,270} {
        \draw[fill] (\x:0.866 cm) -- (\x + 180:0.866 cm);}
\end{tikzpicture}

\begin{tikzpicture}[scale=2]
    \foreach \x in {0,72,...,288} {
        \draw[fill] (\x:1 cm) -- (\x + 72:1 cm);
        \draw[fill] (\x:1 cm) -- (\x + 180:0.809 cm);}
\end{tikzpicture}
\end{document}

But I would like know how to put this pictures together and fill the space within polygons.

---

This was my solution:

\documentclass{report}
\usepackage{tikz}

\definecolor{fondo}{rgb}{0.898,0.996,0.898}
\definecolor{diagonal}{rgb}{0.466,0,0}

\begin{document}

\begin{center}
\begin{tikzpicture}[scale=2]
\begin{scope}
    \draw[fill=fondo,very thick] (0:1 cm) -- (72:1 cm) -- (144:1 cm) -- (216:1 cm) -- (288:1 cm) -- cycle;
    \foreach \x in {0,72,...,288} {
        \draw[diagonal,thin] (\x:1 cm) -- (\x + 180:0.809 cm);}
\end{scope}

\begin{scope}[xshift=3cm]
    \draw[fill=fondo,very thick] (0:1 cm) -- (60:1 cm) -- (120:1 cm) -- (180:1 cm) -- (240:1 cm) -- (300:1 cm) -- cycle;
    \foreach \x in {0,60,...,300} {
        \draw[diagonal,thin] (\x:1 cm) -- (\x + 180:1 cm);}
    \foreach \x in {30,90,...,270} {
        \draw[diagonal,thin] (\x:0.866 cm) -- (\x + 180:0.866 cm);}
\end{scope}
\end{tikzpicture}
\end{center}

\end{document}

Answer 1

You can put the two figures together by using scope. To fill polygons, you need to make sure you actually have a polygon (i.e., at least three line segments in one \draw). I've done that in the code below:

\documentclass{standalone}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}[scale=2]
\begin{scope}
    \foreach \x in {0,60,...,300} {
        \draw[fill=blue!25] (0, 0) -- (\x:1 cm) -- (\x + 30:0.866 cm) -- cycle;
        \draw[fill=blue!50] (0, 0) -- (\x + 30:0.866 cm) -- (\x + 60:1 cm) -- cycle;
    }
\end{scope}
\begin{scope}[xshift=2cm]
    \foreach \x in {0,72,...,288} {
        \draw[fill=blue!25] (0, 0) -- (\x:1 cm) -- (\x + 36:0.809 cm) -- cycle;
        \draw[fill=blue!50] (0, 0) -- (\x + 36:0.809 cm) -- (\x + 72:1 cm) -- cycle;
    }
\end{scope}
\end{tikzpicture}
\end{document}

(The cycle keyword just means "draw a line segment back to the initial point in the \draw statement.)

And, just for my own amusement, here is a generalization that works for any n-gon.

\documentclass{standalone}
\usepackage{tikz}

\newcommand\polygon[2][]{
  \pgfmathsetmacro{\angle}{360/#2}
  \pgfmathsetmacro{\startangle}{-90 + \angle/2}
  \pgfmathsetmacro{\y}{cos(\angle/2)}
  \begin{scope}[#1]
    \foreach \i in {1,2,...,#2} {
      \pgfmathsetmacro{\x}{\startangle + \angle*\i}
      \draw[fill=blue!35] (0, 0) -- (\x:1 cm) -- (\x + \angle/2:\y cm) -- cycle;
      \draw[fill=blue!50] (0, 0) -- (\x + \angle/2:\y cm) -- (\x + \angle:1 cm) -- cycle;
    }
  \end{scope}
}

\begin{document}
\begin{tikzpicture}
  \polygon{5}
  \polygon[xshift=2.2cm]{6}
  \polygon[xshift=4.4cm]{7}
  \polygon[xshift=6.6cm]{8}
\end{tikzpicture}
\end{document}

Answer 2

Similar results can be obtained with a regular polygon shape. In this case, a pic helps to draw the node and fill it with those stripes in one macro.

\documentclass[tikz,border=2mm]{standalone}
\usetikzlibrary{shapes.geometric}

\begin{document}

\tikzset{
    bicolor polygon/.pic = {
        \node[regular polygon, regular polygon sides=#1,
        minimum size=4cm, draw, fill=blue!50,
        outer sep=0pt] at (0,0) (-node){};
        \foreach \i in {1,2,...,#1}
             \draw[fill=blue!25] (-node.corner \i)
                 --(-node.side \i)--(-node.center)--cycle;
    }}

\begin{tikzpicture}

\foreach \i [count=\d from 0]  in {5,6,...,10}
    \draw (4cm*\d,0) pic (a) {bicolor polygon=\i};

\end{tikzpicture}

\end{document}