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Resolved How does one update the Bvh after modifying a model?

Discussion in 'Graphics Dev Blitz Day 2023 - Q&A' started by sacb0y, May 24, 2023.

  1. sacb0y

    sacb0y

    Joined:
    May 9, 2016
    Posts:
    874
    Something I noticed in my experiments with raytracing and HDRP is that if I modify a model with something like UModeler the raytracing would then be incorrect for a while.

    It took me a while to realize why but my guess is the mesh used for the raytracing information isn't updated.

    Is there a manual solution for this or do I need to bug the UModeler dev?
     
    sacb0y, May 24, 2023
    #1
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  2. INedelcu

    INedelcu

    Unity Technologies

    Joined:
    Jul 14, 2015
    Posts:
    173
    Hi! I'm not familiar with UModeler. We do intercept changes to Meshes when for example the asset gets deleted or updated or when you change import settings and reimport it pressing Apply.
    By default Renderers assume that their Meshes are considered as static geometry where the mesh content doesn't change. This is best for GPU performance because the BVH is static. If UModeler uses dynamic Mesh contents then you'll need to set Ray Tracing Mode to Dynamic Geometry in the Renderer inspector.
     

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    INedelcu, May 26, 2023
    #2
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