% Copyright 2019 by Till Tantau
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\section{Quick Commands}

This section explains the ``quick'' commands of \pgfname. These commands are
executed more quickly than the normal commands of \pgfname, but offer less
functionality. You should use these commands only if you either have a very
large number of commands that need to be processed or if you expect your
commands to be executed very often.


\subsection{Quick Coordinate Commands}

\begin{command}{\pgfqpoint\marg{x}\marg{y}}
    This command does the same as |\pgfpoint|, but \meta{x} and \meta{y} must
    be simple dimensions like |1pt| or |1cm|. Things like |2ex| or |2cm+1pt|
    are not allowed.
\end{command}

\begin{command}{\pgfqpointxy\marg{$s_x$}\marg{$s_y$}}
    This command does the same as |\pgfpointxy|, but \meta{$s_x$} and
    \meta{$s_y$} must be simple numbers without unit, like |1.234| or |5.0|.
    Mathematical expressions or units are not allowed.
\end{command}

\begin{command}{\pgfqpointxyz\marg{$s_x$}\marg{$s_y$}\marg{$s_z$}}
    As |\pgfqpointxy|, but for three-dimensional coordinates. Any argument
    needs to be a number without unit.
\end{command}

\begin{command}{\pgfqpointscale\marg{factor}\marg{coordinate}}
    As |\pgfpointscale|, but \marg{factor} must be a simple number without
    unit, as for the other ``quick'' commands.
\end{command}


\subsection{Quick Path Construction Commands}

The difference between the quick and the normal path commands is that the quick
path commands
%
\begin{itemize}
    \item do not keep track of the bounding boxes,
    \item do not allow you to arc corners,
    \item do not apply coordinate transformations.
\end{itemize}

However, they do use the soft-path subsystem (see
Section~\ref{section-soft-paths} for details), which allows you to mix quick
and normal path commands arbitrarily.

All quick path construction commands start with |\pgfpathq|.

\begin{command}{\pgfpathqmoveto\marg{x dimension}\marg{y dimension}}
    Either starts a path or starts a new part of a path at the coordinate
    $(\meta{x dimension},\meta{y dimension})$. The coordinate is \emph{not}
    transformed by the current coordinate transformation matrix. However, any
    low-level transformations apply.
    %
\begin{codeexample}[]
\begin{tikzpicture}
  \draw[help lines] (0,0) grid (3,2);
  \pgftransformxshift{1cm}
  \pgfpathqmoveto{0pt}{0pt} % not transformed
  \pgfpathqlineto{1cm}{1cm} % not transformed
  \pgfpathlineto{\pgfpoint{2cm}{0cm}}
  \pgfusepath{stroke}
\end{tikzpicture}
\end{codeexample}
    %
\end{command}

\begin{command}{\pgfpathqlineto\marg{x dimension}\marg{y dimension}}
    The quick version of the line-to operation.
\end{command}

\begin{command}{\pgfpathqcurveto\marg{$s^1_x$}\marg{$s^1_y$}\marg{$s^2_x$}\marg{$s^2_y$}\marg{$t_x$}\marg{$t_y$}}
    The quick version of the curve-to operation. The first support point is
    $(s^1_x,s^1_y)$, the second support point is  $(s^2_x,s^2_y)$, and the
    target is $(t_x,t_y)$.
    %
\begin{codeexample}[]
\begin{tikzpicture}
  \draw[help lines] (0,0) grid (3,2);
  \pgfpathqmoveto{0pt}{0pt}
  \pgfpathqcurveto{1cm}{1cm}{2cm}{1cm}{3cm}{0cm}
  \pgfusepath{stroke}
\end{tikzpicture}
\end{codeexample}
    %
\end{command}

\begin{command}{\pgfpathqcircle\marg{radius}}
    Adds a radius around the origin of the given \meta{radius}. This command is
    orders of magnitude faster than |\pgfcircle{\pgfpointorigin}{|\meta{radius}|}|.
    %
\begin{codeexample}[]
\colorlet{examplefill}{yellow!80!black}
\begin{tikzpicture}
  \draw[help lines] (0,0) grid (1,1);
  \pgfpathqcircle{10pt}
  \pgfsetfillcolor{examplefill}
  \pgfusepath{stroke,fill}
\end{tikzpicture}
\end{codeexample}
    %
\end{command}


\subsection{Quick Path Usage Commands}

The quick path usage commands perform similar tasks as |\pgfusepath|, but they
%
\begin{itemize}
    \item do not add arrows,
    \item do not modify the path in any way, in particular,
    \item ends are not shortened,
    \item corners are not replaced by arcs.
\end{itemize}

Note that you \emph{have to} use the quick versions in the code of arrow tip
definitions since, inside these definition, you obviously do not want arrows to
be drawn.

\begin{command}{\pgfusepathqstroke}
    Strokes the path without further ado. No arrows are drawn, no corners are
    arced.
    %
\begin{codeexample}[]
\begin{pgfpicture}
  \pgfpathqcircle{5pt}
  \pgfusepathqstroke
\end{pgfpicture}
\end{codeexample}
    %
\end{command}

\begin{command}{\pgfusepathqfill}
    Fills the path without further ado.
\end{command}

\begin{command}{\pgfusepathqfillstroke}
    Fills and then strokes the path without further ado.
\end{command}

\begin{command}{\pgfusepathqclip}
    Clips all subsequent drawings against the current path. The path is not
    processed.
\end{command}


\subsection{Quick Text Box Commands}

\begin{command}{\pgfqbox\marg{box number}}
    This command inserts a \TeX\ box into a |{pgfpicture}| by ``escaping'' to
    \TeX, inserting the box number \meta{box number} at the origin, and then
    returning to the typesetting the picture.
\end{command}

\begin{command}{\pgfqboxsynced\marg{box number}}
    This command works similarly to the |\pgfqbox| command. However, before
    inserting the text in \meta{box number}, the current coordinate
    transformation matrix is applied to the current canvas transformation
    matrix (is it ``synced'' with this matrix, hence the name).

    Thus, this command basically has the same effect as if you first called
    |\pgflowlevelsynccm| followed by |\pgfqbox|. However, this command will use
    |\hskip| and |\raise| commands for the ``translational part'' of the
    coordinate transformation matrix, instead of adding the translational part
    to the current canvas transformation matrix directly. Both methods have the
    same effect (box \meta{box number} is translated to where it should be),
    but the method used by |\pgfqboxsynced| ensures that hyperlinks are placed
    correctly. Note that scaling and rotation will not (cannot, even) apply to
    hyperlinks.
\end{command}


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