Microsoft HoloLens [Virtual Reality, Augmented Reality, Holograms]

Discussion in 'VR and AR' started by Jwm, Jan 21, 2015.

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  1. hughJ

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    Occluding light is easy enough, I think the problem is occluding it at a specific focus distance such that the dark dots are actually in the same plane of focus as the virtual image, and doing that while somehow seeing the rest of the world without any distortion introduced by the optical path that's manipulating the occlusion filter.
     
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  2. milk

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    Yes, for HoloLens to ever work as advertised, they'd need both subtractive and aditive display. Maybe pairing different tech that can do each is the way.
    Of course, once you have a great aditive display, the subtractive one might as well just be a binary 100% black or 100% transparent mask, with the aditive display addinf the desired color on top of it. That might increase the necessity for absolute precision in the alighnent of both displays and of the AR image with the real world one (both from display side, rendering and tracking)
    Say, you want to supperimpose an object to the world, which also casts a semi-transparent shadow. If you only have a binary light mask for subtraction, the additive display has to add both the colors of the rendered object, but it also has to RE-draw the real world image that is suposed to be behind the object's shadow on top of the hard full black one to make it look transparent and fuzzy. Imagine the ground at wich the shadow is projected has a well defined and contrasty pattern. Say, a tiled floor with different colours. Any mismatch between the re-added image and the real world one will make the ground look lumpy or distorted.
    For an even harder problem, imagine the main object itself you are rendering is made of a colored partially transparent material like glass (although in this one the distortion's might pass as a feature, as simulated optics of light refraction...) or thick dark smoke with very smooth edges...
    For this to introduce no mismatch between what the user is actually seeing through the display and what holo lens thinks he is seeing, holo lens has to reproject the footage it gets from the camera into the exact perspective of the user's eye, in real time, with parallax adjustment and all. Tracking precision and lag will also be made even more necessary, or, it's failings will introduce even more glaring artifacts.
    EDIT: Also, fuzzy (like soft shadows penumbra or Smoke or even edge AA if you wanna go ambitious) edges of any kind will also require extremelly precise calibration of camera, additive display, shadow mask and even the lenses transparent material so that resulting colors match closely enough for soft transitions like those to be completely seamless. It's hell!
     
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  3. Shifty Geezer

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    If you're able to composite perfectly realistic visuals over the real-world image, you may as well just use opaque glasses and video displays for the real world with virtual content superimposed.
     
  4. milk

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    exactly

    or, if you can't, then you might wanna look into a set of display technologies that can both add and subtract light well.
     
    #1084 milk, Aug 13, 2019
    Last edited by a moderator: Aug 13, 2019
  5. DSoup

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    Composited sounds better, 'superimposed' is from the 80s! :runaway:
     
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