VTKCamera difference between focal point and position

Question

I am using the vtkCamera and would am trying to move it around and make it look at a certain point. For example, if I want to put the camera at position (x,y,z) and make it look at (0,0,0) for example with gluLookAt in openGL we would set the eye coordinates to (x,y,z) and the centre coordinates to (0,0,0) and the up vector to (0,1,0).

In vtk however, using the vtkCamera we have three separate methods, namely setPosition, setFocalPoint and setViewUp

my question is what do setPositon and setFocalPoint correspond to?

Thanks

Answer 1

setPosition corresponds to eye coordinates. setFocalPoint corresponds to where the camera is looking, so gluLookAt. It functions the same way as both openGL and DirectX in that sense.