\section{Getting started}

\subsection{The first code}
A quick introduction to get you started. We assume that the following packages are installed:  \tkzNamePack{tkz-euclide}, and \tkzNamePack{tkz-elements}.
Compile the following code using the \tkzEngine{lualatex} engine; you should obtain a line passing through points $A$ and $B$.

\begin{mybox}{}
\begin{minipage}{.6\textwidth}
  \begin{tkzexample}[code only]
  % !TEX TS-program = lualatex
  \documentclass{article}
  \usepackage[mini]{tkz-euclide}
  \usepackage{tkz-elements}
  \begin{document}
  \directlua{
    init_elements()
    z.A = point(0, 1)
    % or z.A = point:new(0, 1)
    z.B = point(2, 0)
  }
  \begin{tikzpicture}
   \tkzGetNodes
   \tkzDrawLine(A,B)
   \tkzDrawPoints(A,B)
   \tkzLabelPoints(A,B)
  \end{tikzpicture}
  \end{document}
  \end{tkzexample}
\end{minipage}
\begin{minipage}{.4\textwidth}
  \directlua{
    z.A = point(0, 1)
    z.B = point(2, 0)
  }
  \begin{tikzpicture}
   \tkzGetNodes
   \tkzDrawLine(A,B)
   \tkzDrawPoints(A,B)
   \tkzLabelPoints(A,B)
  \end{tikzpicture}
\end{minipage}
\end{mybox}

\subsection{Key points}

These points will be essential for most of the codes in this documentation.

\begin{itemize}
\item \verb|% !TEX TS-program = lualatex|.
It is essential to compile with \code{lualatex}. This line is not necessary if your configuration is suitable for compilation with \code{lualatex}.
\item \verb|\usepackage[mini]{tkz-euclide}|. You can do without my \tkzNamePack{tkz-euclide} package, but if you use it, it is best to use it with the \code{mini} option. This option avoids loading all the macros used to perform calculations. These will be handled by \code{lua}.
\item \verb|\usepackage{tkz-elements}|. Mandatory! This package must be loaded in order to use it. It provides several macros to support \tkzNamePack{tkz-euclide}, as well as a multitude of mathematical functions written using \code{lua}.
\item \verb| \directlua{ ... }|. Mandatory! The functions of the package will be placed in the body of this macro.
\item \verb|init_elements()|. First function of the package that we will define as mandatory. It allows you to clear all global variables that you may have used in previous code.
\item \verb|\tkzGetNodes|. Mandatory!! First macro to be placed in the \code{tikzpicture} environment. Without this macro, the points defined in the \code{lua} section will not be recognised as \code{nodes}.
\end{itemize}

\subsection{Testing}

To test your installation and follow the examples in this documentation, you need to load two packages: \tkzNamePack{tkz-euclide} and \tkzNamePack{tkz-elements}. The first package automatically loads \tkzNamePack{\TIKZ}, which is necessary for all graphical rendering.


The \tkzname{Lua} code is provided as an argument to the \tkzMacro{lualatex}{directlua} macro. I will often see  this code block as the \tkzname{Lua part}\footnote{This code can also be placed in an external file, e.g., \texttt{file.lua}.}. This part depends entirely on the \tkzNamePack{tkz-elements} package.

A crucial component in the \tkzEnv{tikz}{tikzpicture} environment is the macro \tkzMacro{tkz-elements}{tkzGetNodes}. This macro transfers the points defined in \tkzname{Lua} to \tkzNamePack{\TIKZ} by creating the corresponding nodes. All such points are stored in a table named \tkzname{z} and are accessed using the syntax \tkzname{z.label}. These labels are then reused within \tkzNamePack{tkz-euclide}.

When you define a point by assigning it a label and coordinates, it is internally represented as a complex number — the affix of the point. This representation allows the point to be located within an orthonormal Cartesian coordinate system.

If you want to use a different method for rendering your objects, this is the macro to modify. For example, Section~\ref{sec:metapost} presents \tkzMacro{tkz-elements}{tkzGetNodesMP}, a variant that enables communication with \code{MetaPost}.

Another essential element is the use of the function \tkzFct{tkz-elements}{init\_elements()}, which clears internal tables\footnote{All geometric objects are stored in Lua tables. These tables must be cleaned regularly, especially when creating multiple figures in sequence.} when working with multiple figures.

If everything worked correctly with the previous code, you're ready to begin creating geometric objects. Section~\ref{sec:class_and_object} introduces the available options and object structures.

Finally, it is important to be familiar with basic drawing commands in \tkzNamePack{tkz-euclide}, as they will be used to render the objects defined in \tkzname{Lua}.
\endinput