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MSSAO(Multi-Scale Screen Space Ambient Occlusion)

As we know SSAO is very cheap and reliable ao soluiton but you absolutely pinpoint where it lacks: "details". I considered using VXAO but it is not cheap HBAO isn't that cheap either. Here is a comprasion between most common AO types and MSSAO(Blender for the base point):

Here is the scientific document for the method. https://www.comp.nus.edu.sg/~lowkl/publications/mssao_visual_computer_2012.pdf
Here is the slide for easier understanding: https://pdfs.semanticscholar.org/4f70/7bf1658e6504caf4af09bfd3b24978ea2c5f.pdf

I know HBAO+ is released but this method is far more cheap as you can see on that table in the end of the writing(They tested on GTX 460M! and it is 23ms average). I believe this method will give us far more superior visuals than just SSAO. This feature is a must in my opinion.