This is a Houdini Digital Asset (HDA) to produce Lookout Tower inside of Houdini or in other packages where Houdini Engine is available like Unreal Engine 4 or Maya. It offers a lot of parameters to tweak the style of support; the cabin itself, the deck and also for the staircase that leads to it.
It's possible to specify a mesh for the window and the door to customize the cabin further.
Everything is UVed.
The video is a simple OpenGL render from Houdini.