[vtkusers] how to draw with exact physical dimension (on screen)

[David Gobbi]

Hi Elvis,

I've tried doing this in the past, but the pixel sizes reported by the operating
system are only approximate and are sometimes wildly inaccurate.  VTK
itself has no way of retrieving this information, as far as I am aware.

In the end, I just applied a ruler to the screen :)

  David



On Thu, Jun 5, 2014 at 7:17 AM, Elvis Chen <elvis.chen at gmail.com> wrote:
> hi all,
>
> Is there a way to draw a geometrical objects that will show up on the screen
> with known physical dimension in vtk?
>
> That is, say if I want to draw a square of 5cm in dimension, and I want it
> to appear on screen as a square of 5cm^2, how do I specify vtkCamera that
> takes the screen pixel dimension into consideration?
>
> or am I in the wrong track by looking into vtkCamera?
>
> any help is very much appreciated,