Try this code and see if it makes sense: Fake Invisible Screen
If you do not need Processing, you could just write a simple java application although you might need to use other non-Processing code.
I am thinking you could set the size of the window to the minimum which is 100x100 and then use the robot class to move your window off the visible screen, like moving it to one corner of your window. I do not have a demo but you should find some leads if you search for setLocation()
.
Try this:
- https://discourse.processing.org/search?q=setlocation
- https://discourse.processing.org/search?q=robot
I am just thinking loud…
Kf