[vtkusers] Chart: coordinate conversions

[Marcus D. Hanwell]

On Fri, Dec 24, 2010 at 2:11 AM, nclemeur <nclemeur at gmail.com> wrote:
>
> Hello,
>
> Is there an easy way to convert the coordinate contained in a
> vtkContextMouseEvent into the world coordinate for a vtkChartXY. I have
> tried using the static method
> vtkInteractorObserver::ComputeDisplayToWorld(...) which seemd to be the
> recommended way for normal 3D object. But it does not seems to work (ie the
> value are not really the ones I am expecting).
>
I am not clear about which world coordinates you mean - pixel
coordinates in screen space? The vtkContextMouseEvent object contains
the item position (Pos), then the Scene and Screen positions, see,

http://www.vtk.org/doc/nightly/html/classvtkContextMouseEvent.html

It also contains the last position of each of the above. You can of
course use the 2D transforms, but in many cases there is no need.

Marcus