How to hatch pie charts in Tikz pgf?

Question

I am trying to implement Bordaigorl's answer to create pie charts with patterns. However, with my MWE I get the following errors:

Package pgfkeys Error: I do not know the key '/tikz/slice type/.style 3 args' and I am going to ignore it. Perhaps you misspelled it.

I modified the slice type (in MWE) in pie chart to get a third argument for patterns, which does not work as I expected. How to get patterns in slice types in Tikz pgf?

MWE

\documentclass[border=10pt,multi,tikz]{standalone}
\usetikzlibrary{patterns}
\definecolor{rosso}{RGB}{220,57,18}
\definecolor{giallo}{RGB}{255,153,0}
\definecolor{blu}{RGB}{102,140,217}
\definecolor{verde}{RGB}{16,150,24}
\definecolor{viola}{RGB}{153,0,153}

\makeatletter

\tikzstyle{chart}=[
    legend label/.style={font={\scriptsize},anchor=west,align=left},
    legend box/.style={rectangle, draw, minimum size=5pt},
    axis/.style={black,semithick,->},
    axis label/.style={anchor=east,font={\tiny}},
]

\tikzstyle{bar chart}=[
    chart,
    bar width/.code={
        \pgfmathparse{##1/2}
        \global\let\bar@w\pgfmathresult
    },
    bar/.style={very thick, draw=white},
    bar label/.style={font={\bf\small},anchor=north},
    bar value/.style={font={\footnotesize}},
    bar width=.75,
]

\tikzstyle{pie chart}=[
    chart,
    slice/.style={line cap=round, line join=round, very thick,draw=white},
    pie title/.style={font={\bf}},
    slice type/.style 3 args={
        ##1/.style={fill=##2,pattern=##3},
        values of ##1/.style={}
    }
]

\pgfdeclarelayer{background}
\pgfdeclarelayer{foreground}
\pgfsetlayers{background,main,foreground}


\newcommand{\pie}[3][]{
    \begin{scope}[#1]
    \pgfmathsetmacro{\curA}{90}
    \pgfmathsetmacro{\r}{1}
    \def\c{(0,0)}
    \node[pie title] at (90:1.3) {#2};
    \foreach \v/\s in{#3}{
        \pgfmathsetmacro{\deltaA}{\v/100*360}
        \pgfmathsetmacro{\nextA}{\curA + \deltaA}
        \pgfmathsetmacro{\midA}{(\curA+\nextA)/2}

        \path[slice,\s] \c
            -- +(\curA:\r)
            arc (\curA:\nextA:\r)
            -- cycle;
        \pgfmathsetmacro{\d}{max((\deltaA * -(.5/50) + 1) , .5)}

        \begin{pgfonlayer}{foreground}
        \path \c -- node[pos=\d,pie values,values of \s]{$\v\%$} +(\midA:\r);
        \end{pgfonlayer}

        \global\let\curA\nextA
    }
    \end{scope}
}

\newcommand{\legend}[2][]{
    \begin{scope}[#1]
    \path
        \foreach \n/\s in {#2}
            {
                  ++(0,-10pt) node[\s,legend box] {} +(5pt,0) node[legend label] {\n}
            }
    ;
    \end{scope}
}

\begin{document}
\begin{tikzpicture}
[
    pie chart,
    slice type={comet}{blu,dots},
    slice type={legno}{rosso,grid},
    slice type={coltello}{giallo,north west lines},
    slice type={sedia}{viola,crosshatch},
    slice type={caffe}{verde,vertical lines},
    pie values/.style={font={\small}},
    scale=2
]
    \pie{2008}{73/comet,13/legno,7/sedia,7/coltello}
    \pie[xshift=2.2cm,values of coltello/.style={pos=1.1}]%
        {2009}{52/comet,23/legno,17/sedia,3/coltello,5/caffe}
    \pie[xshift=4.4cm,values of caffe/.style={pos=1.1}]%
        {2010}{56/comet,26/legno,9/sedia,7/coltello,2/caffe}

    \legend[shift={(0cm,-1cm)}]{{Comet (Pordenone)}/comet, {Wood and furniture (Livenza)}/legno, {Knife (Maniago)}/coltello}
    \legend[shift={(3cm,-1cm)}]{{Chair (Manzano)}/sedia, {Coffee (Trieste)}/caffe}
\end{tikzpicture}
\end{document}

Answer 1

First of all, there is no such thing as style 3 args. There is style n args, but that is used as

stylename/.style n args={<number of arguments>}{<style definition>}

So you need to change the syntax of your style definition to

slice type/.style n args={3}{ ... }

And having done that, you need to take percusses' comment into account, and use

slice type={comet}{blu}{dots}

not

slice type={comet}{blu,dots}

as the latter has two arguments, not three.

Finally I changed from \tikzstyle to \tikzset, as the former is considered deprecated, and I changed from \bf to \bfseries as \bf has been deprecated for about 25 years.

\documentclass[border=10pt,multi,tikz]{standalone}
\usetikzlibrary{patterns}
\definecolor{rosso}{RGB}{220,57,18}
\definecolor{giallo}{RGB}{255,153,0}
\definecolor{blu}{RGB}{102,140,217}
\definecolor{verde}{RGB}{16,150,24}
\definecolor{viola}{RGB}{153,0,153}



\tikzset{
  chart/.style={
    legend label/.style={font={\scriptsize},anchor=west,align=left},
    legend box/.style={rectangle, draw, minimum size=5pt},
    axis/.style={black,semithick,->},
    axis label/.style={anchor=east,font={\tiny}},
  },
  bar chart/.style={
    chart,
    bar width/.code={
        \pgfmathparse{##1/2}
        \global\let\bar@w\pgfmathresult
    },
    bar/.style={very thick, draw=white},
    bar label/.style={font={\bfseries\small},anchor=north},
    bar value/.style={font={\footnotesize}},
    bar width=.75,
  },
  pie chart/.style={
    chart,
    slice/.style={line cap=round, line join=round, very thick,draw=white},
    pie title/.style={font={\bfseries}},
    slice type/.style n args={3}{
        ##1/.style={pattern color=##2,pattern=##3},
        values of ##1/.style={}
    }
}}
\pgfdeclarelayer{background}
\pgfdeclarelayer{foreground}
\pgfsetlayers{background,main,foreground}


\newcommand{\pie}[3][]{
    \begin{scope}[#1]
    \pgfmathsetmacro{\curA}{90}
    \pgfmathsetmacro{\r}{1}
    \def\c{(0,0)}
    \node[pie title] at (90:1.3) {#2};
    \foreach \v/\s in{#3}{
        \pgfmathsetmacro{\deltaA}{\v/100*360}
        \pgfmathsetmacro{\nextA}{\curA + \deltaA}
        \pgfmathsetmacro{\midA}{(\curA+\nextA)/2}

        \path[slice,\s] \c
            -- +(\curA:\r)
            arc (\curA:\nextA:\r)
            -- cycle;
        \pgfmathsetmacro{\d}{max((\deltaA * -(.5/50) + 1) , .5)}

        \begin{pgfonlayer}{foreground}
        \path \c -- node[pos=\d,pie values,values of \s]{$\v\%$} +(\midA:\r);
        \end{pgfonlayer}

        \global\let\curA\nextA
    }
    \end{scope}
}

\newcommand{\legend}[2][]{
    \begin{scope}[#1]
    \path
        \foreach \n/\s in {#2}
            {
                  ++(0,-10pt) node[\s,legend box] {} +(5pt,0) node[legend label] {\n}
            }
    ;
    \end{scope}
}

\begin{document}
\begin{tikzpicture}
[
    pie chart,
    slice type={comet}{blu}{dots},
    slice type={legno}{rosso}{grid},
    slice type={coltello}{giallo}{north west lines},
    slice type={sedia}{viola}{crosshatch},
    slice type={caffe}{verde}{vertical lines},
    pie values/.style={font={\small}},
    scale=2
]
    \pie{2008}{73/comet,13/legno,7/sedia,7/coltello}
    \pie[xshift=2.2cm,values of coltello/.style={pos=1.1}]%
        {2009}{52/comet,23/legno,17/sedia,3/coltello,5/caffe}
    \pie[xshift=4.4cm,values of caffe/.style={pos=1.1}]%
        {2010}{56/comet,26/legno,9/sedia,7/coltello,2/caffe}

    \legend[shift={(0cm,-1cm)}]{{Comet (Pordenone)}/comet, {Wood and furniture (Livenza)}/legno, {Knife (Maniago)}/coltello}
    \legend[shift={(3cm,-1cm)}]{{Chair (Manzano)}/sedia, {Coffee (Trieste)}/caffe}
\end{tikzpicture}
\end{document}