Search Unity

Question about light probes

Discussion in 'Global Illumination' started by Enigma229, Oct 4, 2021.

  1. Enigma229

    Enigma229

    Joined:
    Aug 6, 2019
    Posts:
    135
    I'm doing an camera animation of an object in a room. Nothing will be moving except the camera. What is the benefit of using light probes vs baking lightmaps?

    Using HDRP btw.
     
  2. Enigma229

    Enigma229

    Joined:
    Aug 6, 2019
    Posts:
    135
  3. Ruchir

    Ruchir

    Joined:
    May 26, 2015
    Posts:
    934
    If it's just for some animated video recording then I would say not much, although you might have to consider Texel sizes to see if it's even viable for you to bake really small objects as there could be light leaking and you may need to adjust lightmap scale of the object accordingly.
    Another consideration would be memory constraints as lightmapping entire scene creates lightmap texture for each object which must be loaded into memory.
    Iteration speed is another point (as you may not move big structure as much, but you may want to adjust a few small pebbles lying here and there)
    I'm not an expert in this matter though, these are just some thoughts from my side ;)
     
  4. hippocoder

    hippocoder

    Digital Ape

    Joined:
    Apr 11, 2010
    Posts:
    29,723
    Lightprobes will contain changing bounce lighting from Enlighten and are suitable also for objects that are hard to lightmap.
     
  5. Enigma229

    Enigma229

    Joined:
    Aug 6, 2019
    Posts:
    135
    Thanks for replying!

    My scene has a hangar with a helicopter inside. All the lights are coming from drop down ceiling lights.

    To get good lighting inside of the helicopter, should I just make all the interior meshes static and bake them? Otherwise if I use Baked Indirect and only set the hangar to be baked, there is no bounced light inside of the cockpit.
     
  6. kristijonas_unity

    kristijonas_unity

    Unity Technologies

    Joined:
    Feb 8, 2018
    Posts:
    1,080
    That is correct. Mark all large meshes as GI contributors (Lightmap static, in other words), and make sure that you have a dense enough light probe network within the hangar. As for small props and meshes that don't contribute to GI much, you could just leave them as dynamic objects.

    To improve the quality of light probe sampling, you could also assign a Light Probe Proxy Volume to your helicopter.
     
  7. Enigma229

    Enigma229

    Joined:
    Aug 6, 2019
    Posts:
    135
    So your saying to create a light probe volume group after marking all the objects I want baked to static?

    If so, shouldn't I mark each object to Receive Global Illumination Light Probes?
     
  8. kristijonas_unity

    kristijonas_unity

    Unity Technologies

    Joined:
    Feb 8, 2018
    Posts:
    1,080
    Only set Receive Global Illumination to Light Probes for dynamic objects, such as your helicopter and props. Also, please make sure that you watch those videos I have linked to in the other thread you've started.
     
  9. Enigma229

    Enigma229

    Joined:
    Aug 6, 2019
    Posts:
    135
    Thank you. The interior is looking better after using an HDRI skybox for soft light and doing a bake and using some volume overrides.