How does the Landmark registration get the "from" position

Support
1

Hi,
In order to make a realtime EM tracker on the physical model, and the needle followed in the virtual model, I tried the Landmark registration tutorial in IGT.
Firstly, using the vtkLandmarkTransform, I can get the expected transform positions.
But when using the Fiducial Registration Wizard, I don’t know how does the module get the “from” markup points position from a video ? The “to” positions are easy from slicer.

image
image1124×590 23.9 KB

The EM tracker is connected using Plus, the realtime transforms can be seen in the transform module.
so, maybe this is near to the truth. :pray:
thanks.