Il est possible de modifier et de compiler cet exemple :
\documentclass[border=10pt]{standalone}
\usepackage{tkz-euclide}
\begin{document}
\begin{tikzpicture}[scale=.5]
\tkzDefPoints{0/0/A,5/0/B,0.8/4/C}
\tkzDefSpcTriangle[excentral,name=J](A,B,C){a,b,c}
\tkzDefSpcTriangle[intouch,name=I](A,B,C){a,b,c}
\tkzDefProjExcenter[name=J](A,B,C)(a,b,c){X,Y,Z}
\tkzDefCircle[in](A,B,C) \tkzGetPoint{I} \tkzGetSecondPoint{T}
\tkzDrawCircles[red](Ja,Xa Jb,Yb Jc,Zc)
\tkzDrawCircle(I,T)
\tkzDrawPolygon[dashed,color=blue](Ja,Jb,Jc)
\tkzDrawLines[add=2 and 2,line width=1pt](A,C A,B B,C)
\tkzDrawSegments(Ja,Xa Ja,Ya Ja,Za
Jb,Xb Jb,Yb Jb,Zb
Jc,Xc Jc,Yc Jc,Zc
I,Ia I,Ib I,Ic)
\tkzMarkRightAngles[size=.2,fill=gray!15](%
Ja,Za,B
Ja,Xa,B
Ja,Ya,C
Jb,Yb,C
Jb,Zb,B
Jb,Xb,C
Jc,Yc,A
Jc,Zc,B
Jc,Xc,C
I,Ia,B
I,Ib,C
I,Ic,A)
\tkzDrawSegments[blue](Jc,C Ja,A Jb,B)
\tkzLabelPoints(Xb,Yc,A,B,C,Xa,Xc,Ya,Yb,Ja,Jb,Jc,I)
\tkzLabelPoints[above right](Za,Zb,Zc)
\tkzLabelPoints[below](Ia,Ib,Ic)
\end{tikzpicture}
\end{document}