system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Trek: TNG] How does the Holodeck simulate large spaces, particularly when two people are far apart from eachother?

I understand that it creates an artificial environment and can sort of move like a treadmill to make you think you are traveling long distances, 

BuT...

I watched the episode last night where this pre-industrial planet is dying so Warf's foster brother transports them into the holodeck, into a simulation of the cave they were in. He then tells them they have to go on a long journey to a new home, at which point they would be transported back down. 

At one point however, somebody says he forgot something and has to go back. Warf lets him go back . How is this accomplished? Isn't the small cube shaped room already changed to a different environment? (where the core group of people currently are). How is he then able to walk away from them such a large distance, back to the starting point? 

Jeff 

edit: i started a new office job recently and was so used to ending all my emails with "-Jeff" that i just instinctively did it with this post... but I'm gonna leave it because i kind of like it.
gpt
I've always pictured it putting up a holographic wall between the groups and displaying the appropriate images on each "side" depending on either groups point of view. One would show the person who left walking towards the horizon while the walkers side would show whatever he left shrinking as his perspective changes. Essentially it would treat the different groups as scenery for the others.