I know that slicer keeps track on physical position of each voxel - as a starting point for registration I would like to display using python or interactively in the same time voxels that correspond to the same physical position in diffrent images.
I suppose it could be done in compare volumes wizard, but to be honest I do not know How
From algorithm perspective
read physical position of the cursor on image A nad get its coordinates (x,y,z)
look in image B and C for voxel closest to (x,y,z) and display its position by some cross or by temporarly changing the color of this voxel or gorup of voxels etc. - for visualization