I just got it to work.
It turns out nDisplay supports some PostProcessing.
With
OutputRemap
, you can control the way the 2D image, generated by nDisplay, maps to the 2D area of the application window
So I used the example from the article, and the following OBJ as remap
v -1.000000 0.000000 1.000000
v 1.000000 0.000000 1.000000
v -1.000000 0.000000 -1.000000
v 1.000000 0.000000 -1.000000
vt 1.000000 1.000000 0.000000
vt 0.000000 1.000000 0.000000
vt 0.000000 0.000000 0.000000
vt 1.000000 0.000000 0.000000
f 1/1 2/2 4/3 3/4