Search Unity

  1. New Unity Live Help updates. Check them out here!

    Dismiss Notice

Multi-Monitor Shared Reflections

Discussion in 'General Graphics' started by TobyADev, Jan 7, 2019.

  1. TobyADev


    Feb 26, 2016
    Hi All,

    I am currently working on a project which involves three monitors set up like the diagram below.
    These monitors will be placed in a location which we have captured a HDR map of, which should supply lifelike (if static) reflections increasing the realism of the display.
    The issue I am running into is that each of the cameras tied to the separate monitors is receiving the full reflection map from a reflection probe, meaning there are clear repeats of the reflection when looking at sufficiently shiny objects creating obvious mistakes, particularly where the screens line up.
    I would like to have the reflections be calculated as through all 3 cameras/monitors were treated as one but cannot find a working solution to it.
    Reflections are created from a HDR map taken at the location the setup will be implemented.
    Below is an example, showing two cameras next to each-other in-front of a large shiny material, where the repeats will be obvious and glaring.
    Hoping someone with better graphics skills than I can come save the day.
  2. Remy_Unity


    Unity Technologies

    Oct 3, 2017
    I think that the issue here is that you have wrongly set up your cameras.
    Environment cubemaps will display as "background" for a camera, depending on it's FOV and rotation, not position.

    Currently, your camera setup is something like this:

    Thus, it's "normal" that the environment cubemaps appears the same for all cameras. Keep in mind that it's like looking at an infinite giant sphere where you're in the center. moving a bit to the left or the right won't change what you see.

    The simplest way is to rotate the side cameras, to have a "faked" wider view, and properly map the environment background:

    The other but sightly more tricky solution is to alter the side cameras projection matrix to have an ultra wide aspect:

    This can be done by script with , or more easily by using the lens shift property of the physical camera : , setting a lens shift x=1 will shift the camera project to be exactly aligned on the right of the original (this will be the camera #3 in my image).

    Hope that helps.
    Last edited: Jan 14, 2019
  3. TobyADev


    Feb 26, 2016
    Thanks Remy, the projection matrix stuff did the trick for what I needed.