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Question Pixel light count problem on flat terrain

Discussion in 'Global Illumination' started by darkonionn, Jun 18, 2021.

  1. darkonionn

    darkonionn

    Joined:
    Nov 1, 2020
    Posts:
    1
    Hey!

    I am working on 2.5D game, with 'Dont Starve' like camera view and graphics, but i have a major issue with pixel light count.

    Whole scene is based on totally flat terrain with NavMesh on it. Now lets suppose that closely to the ground i have a set of point lights (for example 8), with rather small range (but definately reaching terrain surface), ranges of those lights are not overlapping themselves. All the lights are not baked.

    With pixel light count of lets say 3 those lights are starting to blink. Why is that happening? Only one light is illuminating terrain under it, so this piece of terrain should calculate only one light per pixel. Is it because flat terrain is treated as one huge texture that is illuminated by all eight lights? If so, then how to fix it, and divide terrain into much smaller grid?

    Lights are stopping blinking with pixel light count of ~12 which is seriously influencing performance.

    Thanks in advance for ANY help and suggestions :)

    Regards
    Pawel
     

    Attached Files:

    darkonionn, Jun 18, 2021
    #1

  2. kristijonas_unity

    kristijonas_unity

    Unity Technologies

    Joined:
    Feb 8, 2018
    Posts:
    1,080
    This is an inherent limitation of the Forward renderer. Please take a look at the following Unity Learn article which explains the difference between Forward and Deferred rendering paths.
     
    kristijonas_unity, Jun 21, 2021
    #2