Comment by Vinnl

18 hours ago

I read [1], but I still don't quite know what I'm looking at. My guess is a 3D model reconstructed from lots of detailed pictures?

[1] https://en.wikipedia.org/wiki/Gaussian_splatting

13 comments

Vinnl

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jaccola  17 hours ago

Lots of translucent blobs composited to produce the appearance of a strawberry.

There is no mesh or model. The visual surface of the strawberry could be made up of blobs spaced far apart physically and not where the surface appears to be.

This is why they are called radiance fields, they model the light not the geometry.

Practically the blobs positions/rotations can be constrained to better physically match the geometry of a strawberry.

  • KeplerBoy  17 hours ago

    I'm not sure i agree. The blobs are exactly where the surface appear to be because they are constrained by multiple viewing angles.

    Otherwise the splat would fall apart as soon as the viewing angle is changed slightly (Which it absolutely does in many examples on supersplat, you cannot really create an out of distribution view with 3GS, it's not magic)

    • jaccola  17 hours ago

      Yes, my statement was loose. The blob doesn’t really have a position since it is theoretically an infinite distribution in 3 space.

      It has a mean, and that mean doesn’t have to lie on the surface, consider the case where the mean is deep inside the strawberry but its spike contributes to the surface appearance (e.g a seed could be represented this way, or it could be represented by a small well-oriented blob on the surface, the optimiser doesn’t care)

stevepotter  14 hours ago

Others have provided details about how it works. I suggest zooming way in on that image and you'll start 'breaking though' the surface and that'll help you get an idea of how it works. Important thing is there is no defined geometric surface ("mesh"). Also important to know is that it's very, very hard to get a good splat without taking a ton of photos at different angles. It's also really, really easy to create a crappy looking splat. But when it's done right, it's a marvel

  • ZeWaka  9 hours ago

    I don't know, there's plenty of models these days that generate good splats just from objects at home.

    I took maybe 10 pictures of a model I built and threw it at my 3060 during dinner and it came out quite nice.

  • lubesGordi  13 hours ago

    When you say its very very hard to create a good splat, what do you mean? And what is good? I would say that strawberry is very detailed and its a good splat. I also kind of like the way some of the 'rougher' splats look. I feel like they'd work well in a car racing simulator.

  • davnicwil  4 hours ago

    is the point of doing it for the artistic value / challenge or are there other benefits of not using a mesh or physical model of the object?