Reading the step model

Hi friends
I want get the Geometric information of the Step model
I am using the BRep_Tool::Surface(TopoDS_Face face)
From this I get
Handle(Geom_Surface) & I can find the surface type bye using the surface->Dynamic_Type();
Now how to cast to specific type surface . it may spherical,cylinderical Spline etc .
Thanking you

Stephane Routelous's picture

if ( theSurface->IsKind(STANDARD_TYPE(Geom_BSplineSurface)))
Handle_Geom_BSplineSurface B = Handle_Geom_BSplinesurface::DownCast(theSurface);