\input{preamble-standalone.ltx}
\begin{document}

% Ex. No. 83 (Section 10.7 : style tkzreverseclip)

\begin{tikzpicture}[scale=.5]
  \tkzInit[xmin=-5,xmax=5,ymin=-5,ymax=5]
  \pgfinterruptboundingbox
  \tkzDefPoints{-.5/0/P1,.5/0/P2}
  \foreach \i [count=\j from 3] in {2,...,7}{%
      \tkzDefShiftPoint[P\i]({45*(\i-1)}:1 cm){P\j}
  }
  \endpgfinterruptboundingbox
   \tkzClipOutPolygon(P1,P2,P3,P4,P5,P6,P7,P8)
   \tkzCalcLength[cm](P1,P5)\tkzGetLength{r}
  \begin{scope}[blend group=screen]
     \foreach \i in {1,...,8}{%
       \pgfmathparse{100-5*\i}
       \tkzFillCircle[R,color=blue!%
      \pgfmathresult](P\i,\r)
      }
\end{scope}
\end{tikzpicture}

\end{document}
