I am new to VTK in general, and am struggling to find the right place to change the projection parameter that I want.
I am trying to generate a 2D projection of a volume from a particular viewpoint, and have based my experiments so far on the VolumeViewer and VolumeMapperBlendModes examples. In other places this is called a digitally reconstructed radiograph (DRR) but I haven’t found much in VTK that sounds right.
My current attempt is to use the radon transform, and set the camera parameters to get the viewpoint I want. I was assuming that the raycast origin is at (0,0,0), so I set the actor and camera position to some value along the -Z axis, but the projection doesn’t change.
I did also try the parallel projection mode, but that isn’t quite what I need either.
How can I change the geometry of the projection cone, and in particular the source location or ray origin? Or am I going about this in entirely the wrong way?