[vtkusers] How to project 3D points onto 2D image plane?

[Leon Chen]

Hi all,

Now I am stuck on the final part... :(  I have to do some kind of
2d-3d registration via landmarks. In detail, I marked some points on a
3D mesh, and there is a 2D image which contain these corresponding
llandmarks.

My problem is :there are lots of transforms in VTK, but they are 2D-2D
or 3D-3D, but is there a 3D->2D transform method? (of course it is too
hard transform 2D->3D directly) which can transform the 3D points into
2D image coordinates.

I think VTK implement it, because we see the resuilt everyday -- on
the screen, it is 2D. Also, VTK can output the 2D image(such as JPEG
format file) given a 3D input(such as a 3D polydata model). So it is
sure that the 3D->2D projection is ready in VTK, but I just want to
find a similar transformation method, which can help me in the 3D-2D
registration procedure.

I have search the achives, there are some related topics, but no
reply. I am looking forward anyone who can give any ideas about it. It
is really urgent...

Thank you in advance!!!



Leon