Calculating the cameraposition by calibrating with a known object

i would like to project on a 3D object i want to totate later on a rotary disc f.e. a cube. so there is no way to distort the cube in 3d space cause otherwise it will not fit when it´s rotating.
To do this i would like to find a more automatic way to calculate the projectors position in space.
The way to measure the distance and to position the camera by moving up, down, rotate etc. seems to be to complicated and imprecise. I guess there is a much more better way to get the projectors (3d camera) position. Because its like calculating the camera position for augmented reality i was seraching around in that area. But i don´t want to move the projector or camera later, so i have to calculate the projectors position from a “still image”.
So i thought about kind of a “calibratin square”. Is it possibe to distort a square in vvvv by using the homography node or another tools to fit the virtual square to a real one placed in the projection area to get the camera position calculated out of the distorsion ?

thanx for help

Have you seen this?

CalibrateProjector might be handy.

No, i didn´t see that. It looks good. Thank you for the link.