I have a PC with Windows XP and the nVidia stereo 3D drivers installed.
I also have a head-mounted display that can visualize 3D scenes in side-by-side mode (left half of the screen goes to the left eye, right half of the screen goes to the right eye) or top-and bottom mode (top half of the screen goes to the left eye, bottom half of the screen goes to the right eye).

The problem is that the nVidia stereo 3D drivers don't support either of those modes. They do, however, support a vertically interlaced mode where the odd columns are meant for the left eye, and the even columns are meant for the right eye. This is why I'm looking for a post-processing software for Windows XP with the ability to display all odd lines to the left half of the screen, and all even lines to the right half, effectively turning a vertically interlaced picture into a side-by-side picture. Is there anything like that?

EDIT: I know about the iz3D drivers, which run on Windows XP and support side-by-side mode. However, they don't support OpenGL.
I also know about GLDirect, but that only supports pre-2.0 versions of OpenGL (so, no Doom 3, Prey or Quake 4).