\input{preamble-standalone.ltx} \begin{document} % Ex. No. 223 (Section 27.2.2 : Another example of the use of \tkzcname{tkzShowTransformation}) \begin{tikzpicture}[scale=.6] \tkzDefPoints{0/0/A,8/0/B,3.5/10/I} \tkzDefMidPoint(A,B) \tkzGetPoint{O} \tkzDefPointBy[projection=onto A--B](I) \tkzGetPoint{J} \tkzInterLC(I,A)(O,A) \tkzGetPoints{M'}{M} \tkzInterLC(I,B)(O,A) \tkzGetPoints{N}{N'} \tkzDrawSemiCircle[diameter](A,B) \tkzDrawSegments(I,A I,B A,B B,M A,N) \tkzMarkRightAngles(A,M,B A,N,B) \tkzDrawSegment[style=dashed,color=blue](I,J) \tkzShowTransformation[projection=onto A--B, color=red,size=3,gap=-3](I) \tkzDrawPoints[color=red](M,N) \tkzDrawPoints[color=blue](O,A,B,I) \tkzLabelPoints(O) \tkzLabelPoints[above right](N,I) \tkzLabelPoints[below left](M,A) \end{tikzpicture} \end{document}