[vtkusers] vtkTkRenderWidget -width -height

[Wolfram H Volpi]

I have a question.
How can one change width and height of a vtkTkRehderWidget object after it
is already set?

For example, in /vtk/graphics/examples/vol.tcl there are these two lines:

vtkTkRenderWidget .top.f1.f2.f1.f1.ren -width 256 -height 256 
    BindTkRenderWidget .top.f1.f2.f1.f1.ren

Is there a way to change the width and height to 512 latter in the
program?

Thank you,
Wolfv.