There is a View3D property property off the chart object. It defaults to false but if it is set to true the series will dispaly in 3d format.
<igCA:XamChart View3D="False" >
<igCA:XamChart.Series>
<igCA:Series ChartType="Pie" Fill="#FFD21717" Stroke="#FF000000">
<igCA:Series.DataPoints>
<igCA:DataPoint Value="5" />
<igCA:DataPoint Value="7" />
</igCA:Series.DataPoints>
</igCA:Series>
</igCA:XamChart.Series>
</igCA:XamChart>