In the current version of ArcGIS Runtime, multipatch geometry is not supported. This kind of geometry is available in ArcGIS Desktop and ArcGIS Engine via
ArcObjects. With multipatch geometry, it is possible to virtually create any shape, such as the clearance cones around a missile's trajectory, by using triangle strips, triangle fans, triangles, and rings. Here's an example:
This kind of capability will eventually make it to ArcGIS Runtime as the 3D capabilities are expanded. For now, you can still create multisided shapes with the example code that follows, and apply
PictureFillSymbol to them as a form of texture if needed:
// outline ...