visualize data at Gauss points

Hi everyone,

Is is possible to export Gauss point data to vtk file for visualization? At this moment, the GP data will be averaged in an element and visualized in paraview as a cell data. But it is sometimes interesting to visualize GP data directly, e.g. the following figure shows direction of stress in Plaxis:

https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcT0bGeSMheXIvTu8IKMbAiHK3YINKCZP-J-F5cb8foCrfcjUzymDw

Similar figure is presented in this paper (Fig. 11 therein)

http://link.springer.com/article/10.2478%2Fs11600-014-0228-3

I also notice that vtk supports GP data visualization. So it seems an issue of saveVTK function in Escript.

http://www.vtk.org/Wiki/VTK/VTK_integration_point_support

Thanks,
Ning