As far as i know there is no such option in slic3r, but i think you could be able to do it like this:
- define the bed as a rectangle as big as the paper substrate
- design a rectangle with that size and print it
- mark the borders on the printer bed with some tape or marker
- position the paper and there you go
if you need the image as reference to position the objects you could convert the picture to stl in some way, add it to the slicer, position the objects and then remove it.
Edited 1 time(s). Last edit at 02/13/2019 05:50PM by hariseldon78.