\section{Using the compass}    

\subsection{Main macro \tkzcname{tkzCompass}} 
\begin{NewMacroBox}{tkzCompass}{\oarg{local options}\parg{A,B}}%
This macro allows you to leave a compass trace, i.e. an arc at a designated point. The center must be indicated. Several specific options will modify the appearance of the arc as well as TikZ options such as style, color, line thickness etc.

You can define the length of the arc with the option |length| or the option |delta|.

\medskip
\begin{tabular}{lll}%
\toprule
options             & default & definition                        \\ 
\midrule
\TOline{delta} {0 (deg)}{Modifies the angle of the arc by increasing it symmetrically (in degrees)} 
\TOline{length}{1 (cm)}{Changes the length (in cm)} 
\end{tabular}
\end{NewMacroBox} 

\subsubsection{Option \tkzname{length}} 
\begin{tkzexample}[latex=7cm,small]
\begin{tikzpicture}
  \tkzDefPoint(1,1){A}
  \tkzDefPoint(6,1){B}
  \tkzInterCC[R](A,4cm)(B,3cm)
  \tkzGetPoints{C}{D}
  \tkzDrawPoint(C)
  \tkzCompass[color=red,length=1.5](A,C)
  \tkzCompass[color=red](B,C)
  \tkzDrawSegments(A,B A,C B,C)
\end{tikzpicture}
\end{tkzexample}

\subsubsection{Option \tkzname{delta}} 
\begin{tkzexample}[latex=7cm,small]
\begin{tikzpicture} 
  \tkzDefPoint(0,0){A} 
  \tkzDefPoint(5,0){B}
  \tkzInterCC[R](A,4cm)(B,3cm)
  \tkzGetPoints{C}{D}
  \tkzDrawPoints(A,B,C) 
  \tkzCompass[color=red,delta=20](A,C)
  \tkzCompass[color=red,delta=20](B,C) 
  \tkzDrawPolygon(A,B,C)  
  \tkzMarkAngle(A,C,B)
\end{tikzpicture}
\end{tkzexample} 

\subsection{Multiple constructions \tkzcname{tkzCompasss}} 
\begin{NewMacroBox}{tkzCompasss}{\oarg{local options}\parg{pt1,pt2 pt3,pt4,\dots}}%
\tkzHandBomb\ Attention the arguments are lists of two points. This saves a few lines of code.

\medskip
\begin{tabular}{lll}%
\toprule
options             & default & definition                        \\ 
\midrule
\TOline{delta} {0}{Modifies the angle of the arc by increasing it symmetrically} 
\TOline{length}{1}{Changes the length} 
\end{tabular}
\end{NewMacroBox} 

\begin{tkzexample}[latex=7cm,small]
\begin{tikzpicture}[scale=.75]
 \tkzDefPoint(2,2){A}  \tkzDefPoint(5,-2){B}
 \tkzDefPoint(3,4){C}  \tkzDrawPoints(A,B) 
 \tkzDrawPoint[color=red,shape=cross out](C)    
 \tkzCompasss[color=orange](A,B A,C B,C C,B) 
 \tkzShowLine[mediator,color=red,
                             dashed,length = 2](A,B)
 \tkzShowLine[parallel = through C,
                            color=blue,length=2](A,B)
 \tkzDefLine[mediator](A,B)  \tkzGetPoints{i}{j}
 \tkzDefLine[parallel=through C](A,B) \tkzGetPoint{D}
 \tkzDrawLines[add=.6 and .6](C,D A,C B,D)
 \tkzDrawLines(i,j) \tkzDrawPoints(A,B,C,i,j,D)  
 \tkzLabelPoints(A,B,C,i,j,D)
\end{tikzpicture}
\end{tkzexample} 


\subsection{Configuration macro \tkzcname{tkzSetUpCompass}} 

\begin{NewMacroBox}{tkzSetUpCompass}{\oarg{local options}}%
\begin{tabular}{lll}%
options             & default & definition                        \\ 
\midrule
\TOline{line width}  {0.4pt}{line thickness} 
\TOline{color}  {black!50}{line colour} 
\TOline{style}  {solid}{solid line style, dashed,dotted,...}
\end{tabular}
\end{NewMacroBox} 

\subsubsection{Use of \tkzcname{tkzSetUpCompass}}

\begin{tkzexample}[latex=7cm,small]
\begin{tikzpicture}[scale=.75,
	      showbi/.style={bisector,size=2,gap=3}]
  \tkzSetUpCompass[color=blue,line width=.3 pt]
  \tkzDefPoints{0/1/A, 8/3/B, 3/6/C}
  \tkzDrawPolygon(A,B,C)  
  \tkzDefLine[bisector](B,A,C)  \tkzGetPoint{a}
  \tkzDefLine[bisector](C,B,A)  \tkzGetPoint{b}
  \tkzShowLine[showbi](B,A,C)
  \tkzShowLine[showbi](C,B,A)   
  \tkzInterLL(A,a)(B,b) \tkzGetPoint{I}
  \tkzDefPointBy[projection= onto A--B](I)
	 \tkzGetPoint{H}
  \tkzDrawCircle[radius,color=gray](I,H) 
  \tkzDrawSegments[color=gray!50](I,H)
  \tkzDrawLines[add=0 and -.2,color=blue!50 ](A,a B,b) 
	\tkzShowBB
\end{tikzpicture} 
\end{tkzexample} 
\endinput