Its for the npc's.
If an npc's path is obstructed by another entity then it will return 1 otherwise it will return 0.
Desktop: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz (8 CPUs), ~3.6GHz, Windows 10, 64-bit, 16 GB Ram, NVIDIA GeForce GTX 750 Ti, Display Memory: 4018 MB. Resolution 1360x768, Passmark 3528.
Operating System: Windows 10 Home 64-bit (10.0, Build 15063) (15063.rs2_release.170317-1834)
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