RadChartView still doesn't support 3D series and our current planning doesn't include implementing such visualization. However, we have a feature request for 3D series logged in our feedback portal
where you can track its status. You can also take a look at the ChartViewCustomization
help article that demonstrates series with a gradient that mimics depth in the data points fill color.
Keep in mind that we think that 3D charts doesn't bring a better understanding for the plotted data to the end user in a scenario with 2 dimensional data. Furthermore, the additional dimension might be confusing for perceiving the displayed information.
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Feedback Portal
and vote to affect the priority of the items