Pretty well all positive in US, Canada, Australia, Russia and elsewhere. Most LEOs I've come across either ignore me or will catch a friendly eye contact and a smile.
The closest I came to anything less than positive was camping one night along the road in one of the oil regions of Russia. I wasn't particularly trying to hide, but fairly late in the evening (but still light), I awoke to three folks with guns and a jeep. With my limited Russian vocabulary, we fairly quickly established that I was a tourist and that I'd be gone in the morning. I think they were security folks rather than police and they were mostly curious and surprised to find me there.