documentclass[12pt,preview,border=15pt]{standalone}
usepackage{pstricks-add,pst-pers,vecteurs}

begin{document}
begin{pspicture}[linejoin=1](-1,-2)(7,7)
psset{fuyante=95}
xintdefvar aa:= 6.5;

VecDef{A}{0,0,0}
VecDef{F}{5,aa+8,0}
VecDef{C}{0-1,6,0}
VecDef{S}{0,0,aa}
%%
persNodeX(A){A}
persNodeX(F){F}
persNodeX(C){C}
persNodeX(S){S}
%%
ProjectPtOnLine(A)(F)(C){B}{CB}
persNodeX(B){B}
ProjectPtOnLine(S)(B)(A){E}{AE}
persNodeX(E){E}
ProjectPtOnLine(S)(C)(A){F}{AF}
persNodeX(F){F}
%%
foreach Angle/Name in {135/A,-45/C,-45/B,90/S,5/E,5/F}{uput[Angle](Name){$Name$}}
%%
perspectiveX(B)(C){A}{pstRightAngle{A}{B}{C}}
perspectiveX(A)(B){S}{pstRightAngle{A}{E}{B}}
perspectiveX(C)(A){S}{pstRightAngle{A}{F}{C}}
perspectiveX(B)(C){S}{pstTriangleOC[linewidth=1pt]{E}{B}{C}}
  perspectiveX(E)(F){A}{%
     pstTriangleOC[linestyle=none]{A}{E}{F}
     pstCurvAbsNode[PointSymbol=none,PointName=none]{OC_O}{E}{Z}{pstDistVal{3.12}}
     pstCurvAbsNode[PointSymbol=none,PointName=none]{OC_O}{E}{Z1}{pstDistVal{7.3}}
       psarcAB(OC_O)(Z1)(Z)
       psarcAB[linestyle=dashed](OC_O)(Z)(Z1)
}
psline(S)(A)(B)(C)(S)(B)
psline(A)(E)(F)
psLineSegments[linestyle=dashed](A)(C)(A)(F)
end{pspicture}
end{document}