% !TeX root = ./examples/koala.tex
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% This package is part of the TikZlings package
%% A package to bring cute little animals and other beings into tikz
%% Maintained by samcarter
%%
%% Project repository and bug tracker:
%% https://github.com/samcarter/tikzlings
%%
%% Released under the LaTeX Project Public License v1.3c or later
%% See http://www.latex-project.org/lppl.txt
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\ProvidesPackage{tikzlings-koalas}[2022/06/17 version v1.0 Drawing koalas in TikZ]

\RequirePackage{tikz}
\RequirePackage{tikzlings-addons}
\usetikzlibrary{shadows.blur}
\usetikzlibrary{fadings} 

\tikzfading[name=koala@blush,inner color=transparent!50,outer color=transparent!100]

\newcommand*{\koala}[1][]{%
  \begin{scope}%
    \tikzset{/koala/.cd,#1}%
    \koala@draw%
  \end{scope}%
  \thing[#1]%
  % adding hook for users to customise %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \csname koalahookforeground\endcsname
  \csname tikzlinghookforeground\endcsname
  %
}

\newif\ifkoala@blush
\newif\ifkoala@sleeping
\newif\ifkoala@threeD
\newif\ifkoala@back
\newif\ifkoala@contour

\tikzset{
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % Pass unknown keys on to tikz
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  /koala/.search also={/tikz,/pgf,/thing},
  /koala/.cd,
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % body
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  body/.store in     = \koala@body,
  body               = gray!75!white,
  eye/.store in      = \koala@eye,
  eye                = black,   
  mouth/.store in    = \koala@mouth,
  mouth              = \koala@body!40!black,
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % options
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  blush/.code        = \koala@blushtrue
                       \def\koala@blushcolor{#1},
  blush/.default     = red, 
  sleeping/.code     = \koala@sleepingtrue, 
  3D/.code           = \koala@threeDtrue
                       \def\koala@mouth{black},  
  back/.code         = \koala@backtrue,  
  contour/.code      = \koala@contourtrue
                       \def\koala@contour{#1}
                       \def\koala@blushcolor{#1}
                       \def\koala@mouth{#1},
  contour/.default   = black,  
  outline/.forward to = /koala/contour,   
}

\def\koala@draw{%
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % minimal bounding box size 
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \path (-0.88,0.1) rectangle (0.88, 2.35);
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % store the current scale factor
  % from https://github.com/samcarter/tikzlings/issues/3#issuecomment-461373494
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \pgfgettransformentries{\tmpscaleA}{\tmpscaleB}{\tmpscaleC}{\tmpscaleD}{\tmp}{\tmp}%
  \pgfmathsetmacro{\scalingfactor}{sqrt(abs(\tmpscaleA*\tmpscaleD-\tmpscaleB*\tmpscaleC))*sqrt(abs((\pgf@xx/1cm)*(\pgf@yy/1cm)-(\pgf@xy/1cm)*(\pgf@yx/1cm)))}%
  \pgfmathsetmacro{\xscalefactor}{\tmpscaleA}
  \pgfmathsetmacro{\yscalefactor}{\tmpscaleD}
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  % 
  % switch between 2D, 3D and contours, from
  % https://chat.stackexchange.com/transcript/message/45991801#45991801
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \ifkoala@threeD
    \def\koala@part@draw[##1]{\shade[ball color=##1]}
  \else% 3D
    \ifkoala@contour
      \def\koala@part@draw[##1]{\draw[##1,\koala@contour,fill=white,line width=\scalingfactor*0.4pt]}
    \else% contour
      \def\koala@part@draw[##1]{\fill[##1]}
    \fi% contour
  \fi% 3D
  %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % Body parts
  % 
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %
  % adding hook for users to customise %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \csname koalahookbackground\endcsname
  \csname tikzlinghookbackground\endcsname
  %
  % Feet %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \koala@part@draw[\koala@body!50!black] (0.255,0.2) ellipse[x radius=0.23, y radius=0.09]; 
  \koala@part@draw[\koala@body!50!black] (-0.255,0.2) ellipse[x radius=0.23, y radius=0.09];
  %
  % Ears %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \koala@part@draw[\koala@body] (0.405, 2.1) ellipse[x radius=0.3, y radius=0.23];
  \koala@part@draw[\koala@body] (-0.405, 2.1) ellipse[x radius=0.3, y radius=0.23];
  \unless\ifkoala@back
    \koala@part@draw[\koala@body!40!white] (-0.405, 2.1) ellipse[x radius=0.15, y radius=0.12];
    \koala@part@draw[\koala@body!40!white] (0.405, 2.1) ellipse[x radius=0.15, y radius=0.12];
  \fi% back
  %
  % Arms %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \koala@part@draw[\koala@body] (-0.625,1) ellipse[x radius=0.42, y radius=0.13, rotate=70];
  \koala@part@draw[\koala@body!50!black] (-0.745,0.65) ellipse[x radius=0.12, y radius=0.08, rotate=-20];
  \koala@part@draw[\koala@body] (0.625,1) ellipse[x radius=0.42, y radius=0.13, rotate=-70];
  \koala@part@draw[\koala@body!50!black] (0.745,0.65) ellipse[x radius=0.12, y radius=0.08, rotate=20];
  %
  % Body %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \koala@part@draw[\koala@body] (0.595, 0.92) .. controls (0.595, 0.26) and (0.355, 0.18) .. (0, 0.18) .. controls (-0.355, 0.18) and (-0.595, 0.26) .. (-0.595, 0.92) .. controls (-0.605, 1.58) and (-0.335, 2.11) .. (0, 2.11) .. controls (0.335, 2.11) and (0.605, 1.58) .. (0.595, 0.92) -- cycle;
  %
  % Belly %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \unless\ifkoala@back
    \koala@part@draw[\koala@body!40!white] ( 0.425, 0.71) .. controls ( 0.425, 0.41) and ( 0.255, 0.27) .. ( 0    , 0.27) .. controls (-0.255, 0.27) and (-0.425, 0.41) .. (-0.425, 0.71) .. controls (-0.425, 1.01) and (-0.255, 1.20) .. ( 0    , 1.20) .. controls ( 0.225, 1.20) and ( 0.425, 1.01) .. ( 0.425, 0.71) -- cycle;
  \fi% back
  %
  % adding hook for users to customise %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \csname koalahookbelly\endcsname
  \csname tikzlinghookbelly\endcsname
  %
  % Head %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \koala@part@draw[\koala@body] (0,1.67) ellipse[x radius=0.55, y radius=0.45];
  %
  % Show details only from the front %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \unless\ifkoala@back
    %
    % Nose %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    \koala@part@draw[\koala@body!40!black] (-0.1501, 1.5609) .. controls (-0.1784, 1.4833) and (-0.0827, 1.4108) .. ( 0.0000, 1.4108) .. controls ( 0.0827, 1.4108) and ( 0.1784, 1.4833) .. ( 0.1501, 1.5609) .. controls ( 0.1290, 1.6191) and ( 0.1187, 1.6573) .. ( 0.0750, 1.7010) .. controls ( 0.0336, 1.7424) and (-0.0336, 1.7424) .. (-0.0750, 1.7010) .. controls (-0.1187, 1.6573) and (-0.1290, 1.6191) .. (-0.1501, 1.5609) -- cycle;
    %
    % Eyes %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    \ifkoala@sleeping
      \fill[\koala@body!50!black] (0.2534, 1.675) rectangle ++(0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={20:(0.2925, 1.6925)}] (0.29, 1.68) rectangle ++(0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={-20:(0.2143, 1.6925)}] (0.2168, 1.68) rectangle ++(0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={40:(0.3255, 1.7025)}] (0.323, 1.69) rectangle ++(0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={-40:(0.1813, 1.7025)}] (0.1838, 1.69) rectangle ++(0.005, 0.03);
      \fill[\koala@body!50!black] (-0.2534, 1.675) rectangle ++(-0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={-20:(-0.2925, 1.6925)}] (-0.29, 1.68) rectangle ++(-0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={20:(-0.2143, 1.6925)}] (-0.2168, 1.68) rectangle ++(-0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={-40:(-0.3255, 1.7025)}] (-0.323, 1.69) rectangle ++(-0.005, 0.03);
      \fill[\koala@body!50!black,rotate around={40:(-0.1813, 1.7025)}] (-0.1838, 1.69) rectangle ++(-0.005, 0.03);  
      \fill[\koala@body!50!black, even odd rule] (0.3331, 1.741) ..  controls (0.3331, 1.685) and (0.1737, 1.685) .. (0.1737, 1.741) .. controls (0.1737, 1.848) and (0.3331, 1.848) .. (0.3331, 1.741) -- cycle (0.328, 1.741) .. controls   (0.323, 1.705) and   (0.184, 1.705) .. (0.179, 1.741) .. controls   (0.184, 1.843) and   (0.323, 1.843) .. (0.328, 1.741) -- cycle;
      \fill[\koala@body!50!black, even odd rule] (-0.3331, 1.741) ..  controls (-0.3331, 1.685) and (-0.1737, 1.685) .. (-0.1737, 1.741) .. controls (-0.1737, 1.848) and (-0.3331, 1.848) .. (-0.3331, 1.741) -- cycle   (-0.328, 1.741) .. controls     (-0.323, 1.705) and     (-0.184, 1.705) ..     (-0.179, 1.741) .. controls (-0.184, 1.843) and (-0.323, 1.843) .. (-0.328, 1.741) -- cycle;
    \else% sleeping
      \koala@part@draw[\koala@eye] (-0.255, 1.74) circle[radius=0.08]; 
      \koala@part@draw[\koala@eye] (0.255, 1.74) circle[radius=0.08]; 
      \fill[white] (-0.27, 1.76) circle[radius=0.015]; 
      \fill[white] (0.24, 1.76) circle[radius=0.015]; 
    \fi% sleeping
    %
    % Mouth %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    \draw[\koala@mouth,line width=\scalingfactor*0.4pt] (0.115, 1.39) arc [start angle=-40, end angle=-140, radius=0.16];
    %
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %
    % optional
    %
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %
    % Blushed %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    \ifkoala@blush
      \fill[\koala@blushcolor,path fading=koala@blush] (-0.3, 1.52) circle[radius=0.1]; 
      \fill[\koala@blushcolor,path fading=koala@blush] (0.3, 1.52) circle[radius=0.1];
    \fi% blush
    %
  \fi% back
  %
  % adding hook for users to customise %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \csname koalahookbody\endcsname
  \csname tikzlinghookbody\endcsname
  %
}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% Documentation
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\clearpage
%\section[Koala]{Will, the koala}
%
%\emph{The koala was generously contributed by @marmot and is named in honour of a \LaTeX{} developer from Down Under}
%
%\subsection{Package name}
%
%\begin{tcolorbox}[lower separated=false, lefthand width=.8\linewidth]
%\vspace*{0.5cm}
%\lstinline|\usepackage{tikzlings-koalas}| 
%\vspace*{0.5cm}
%\end{tcolorbox}
%
%\subsection{Basic Usage}
%
%\begin{tcblisting}{}
%\koala
%\end{tcblisting}
%
%\subsection{Options}
%
%The basic koala can be modified by changing its colour:
%\begin{tcblisting}{}
%\koala[body=blue]
%\end{tcblisting}
%
%In addition to the colour of the body, the colour of various body parts can be adjusted:
%\begin{tcblisting}{}
%\koala[eye=red]
%\end{tcblisting}
%\begin{tcblisting}{}
%\koala[mouth=red]
%\end{tcblisting}
%
%It can also blush
%\begin{tcblisting}{}
%\koala[blush=red]
%\end{tcblisting}
%
%and if tired, it is going to take a nap:
%\begin{tcblisting}{}
%\koala[sleeping]
%\end{tcblisting}
%
%To view the koala from behind:
%\begin{tcblisting}{}
%\koala[back]
%\end{tcblisting}
%
%The key \lstinline|3D| will make the koala 3-dimensional:
%\begin{tcblisting}{}
%\koala[3D]
%\end{tcblisting}
%
%And finally the \lstinline|contour| key will only draw the outlines:
%\begin{tcblisting}{}
%\koala[contour=black]
%\end{tcblisting}