[vtkusers] vtkPicker returned actor

Lonni Besançon lonni.besancon at gmail.com
Sun Feb 28 12:02:01 EST 2016

Hi David,

I just thought you might be able to help me again.
I use the GetMapperPosition() to get the position of my finger on the slice.
It gives me a x and y position comprised between -0.5 and 0.5.
>From there I would like to get the position of this point in the dataset
which I slice from.
So basically I have a volume with 3 dimensions, and the slice on which my
finger is on is just a slice of width 1 of this dataset. At anytime I know
the UserMatrix of my volume and of my plane. I also know at which depth is
my plane.

What I initially tried is: userMatrixVolume.inverse() * matrixPlane *

The position of my finger is initialised thanks to GetMapperPosition() + the
depth of the plane, the matrixPlane by the current matrix of the plane and
the userMatrixVolume.inverse() is simply the inverse of my userMatrix of the

I thought this would work right away because " userMatrixVolume.inverse() *
matrixPlane" is what I use to create a matrix to use in SetResliceAxes() to
update my slice when the volume or the plane is moved.
However, it does not seem to in that case.

Would you know what I may be doing wrong here?
That's more of a math issue I guess in my case than a general VTK issue

View this message in context: http://vtk.1045678.n5.nabble.com/vtkPicker-returned-actor-tp5736763p5736899.html
Sent from the VTK - Users mailing list archive at Nabble.com.

More information about the vtkusers mailing list