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Unity 2019.1 Moving an Object with an Emmissive Texture

Discussion in 'Global Illumination' started by PhoenixAdvanced, May 18, 2019.

  1. PhoenixAdvanced

    PhoenixAdvanced

    Joined:
    Sep 30, 2016
    Posts:
    140
    Hello.

    I am using Unity 2019.1.

    I have run into a technical/feasibility hitch with my project, and I would be interested in any advice as to how I would solve this.

    I am working on a sci-fi/cyberpunk style game in which lighting, in particular emissive lighting is very important for ambience. I want to have neon signs, computer monitors, various sci fi gadgets, etc casting light into the scene.

    This can be done easily using baked lighting and static objects, which is what I was doing.

    However the issue that I have run into is that the scene takes place on board a spaceship, so all of the scene elements (the neon sign itself, and the scene geometry) are moving. This means that I can't bake lighting. Due to the fact that the scene and the light are both moving, I can't use light probes either.

    Is there any kind of solution for this problem?

    Based on my research, I cannot see any current way to move an object with an emissive texture and still have it cast light into the scene, and onto walls and floors.

    I have found "SEGI", but that seems to have been abandoned. I've also found references to a replacement to SEGI from another developer, as well as a few other "real time Global Illumination" solutions, but I can't find anything concrete on these.

    I am using the standard render pipeline, does the HDRP have support for real time emission?
    What about the new raytracing features that Unity will be supporting later this year, is there some option there to replace baked lighting, assuming I buy an RTX card?
    Could I write a custom shader to do this?
    Is there some other package or source code that I could access or purchase that would add this feature?

    Performance isn't really an issue, since there is only one "starship" in the scene, and it's relatively small. The critical thing is that the ship needs to rotate in space, which means all of it's lights, and interior geometry (and the player and AI on board) need to rotate too.

    Thanks for any advice.
     
  2. KEngelstoft

    KEngelstoft

    Unity Technologies

    Joined:
    Aug 13, 2013
    Posts:
    1,061
    You can let the space ship be static and move the entire universe around it? That would allow you to use precomputed realtime GI or baked lighting...
     
  3. PhoenixAdvanced

    PhoenixAdvanced

    Joined:
    Sep 30, 2016
    Posts:
    140
    That's a great idea, that's exactly what I was doing, and it seemed to work ok. However I eventually had to abandon this because I discovered some issues with it that I just couldn't solve (related to travelling long distances from the origin, etc), so for simplicity I had to go back to a rotating ship model for now.