When we camping together, we all shared a tent (tent rated for eight people means lots of room for three). My wife slept on a cot and my (former) inamorata and I slept on air mattresses. Come morning, my inamorata and I enjoyed some naked goodness; my wife woke up to the noise, looked and saw it was us, and rolled over to go back to sleep.
I never worried about showing affection for one when the other was around. It was nothing I ever thought about. I simply showed affection to whomever I wanted to whenever I wanted to.
As I just began dating another woman, I expect the same sort of thing in the future. I'm not going to worry about it unless one of the ladies says she feels a bit shortchanged, then I'll address that.
So, I say to PDA as you will and expect any shortcomings to get reported. Deal with only real issues and not imaginary issues that may never arise.