public void HighlightBounds(SharpDX.BoundingBox bounds) { var r3d = new Media3D.Rect3D(bounds.Minimum.ToPoint3D(), bounds.Size.ToSize3D()); var b = new Helix.MeshBuilder(); b.AddBoundingBox(r3d, 0.1); b.AddSphere(bounds.Center, 0.1); var geom = b.ToMeshGeometry3D(); box.Geometry = geom; if (!Viewport.Items.Contains(box)) { Viewport.Items.Add(box); } }