A digital image is a soup, of RGB dots of various size.
Gaussian Splatting radically changed the approach to photogrammetry. Prior approaches to generate surface models, and mapping the captures to materials that a renderer would more or less rasterize with physically accuracy were hitting the ceiling of the technique.
NerF was also a revolution but is very compute intensive.
Even a browser, a mid range GPU, can render millions of splats at 60 frames per seconds. That's how fast it goes and less than a million dense scene can already be totally bluf the eye in most possible angles.
Splatting is the most advanced, promising and already delivered on the promise technique for photogrammetry. The limit is that can't do as much in term of modification to point clouds vs surface with great PBR attributes.
No, an image is a well ordered grid of pixels. The 3D variant would be voxels, and Nvidia recently released a project to do scene reconstruction with sparse voxels [0].
If you take these triangles, make them share vertices, and order them in a certain way, you have a mesh. You can then combine some of them into larger flat surfaces when that makes sense, draw thousands of them in one draw call, calculate intersections, volumes, physics, LODs, use textures with image compression instead of millions of colored objects, etc with them. Splatting is one way of answering the question "how do we reproduce these images in a way that lets us generate novel views of the same scene", not "what is the best representation of this 3D scene".
The aim is to find the light field that describes the scene, and if you have solid objects that function can be described on the surface of those objects. Seems like a much more elegant end result than a cloud of separate objects, no matter what shape they have, since that's much closer to how reality works. Obviously we need to handle volumetrics and translucency as well, but if we model the real surfaces as virtual surfaces I think things like reflections and shadow removal will be easier. At least gaussian splats have a hard time with reflections, they look good from some viewing angles, but the reflections are often handled as geometry [1].
I'm not arguing that it doesn't look good or that it doesn't serve a purpose, sometimes a photorealistic novel view of a real scene is all you want. But I still don't think it's the best representation of scenes.
[0] https://svraster.github.io/
[1] https://www.youtube.com/watch?v=yq6gtdpLUCo
I still love this older paper on Plenoxels : https://alexyu.net/plenoxels/
It made so much sense to me: voxels with view dependent color, using eg. spherical gaussians.
I don't know how it compares to newer techniques, probably badly since nobody seems to be talking about it.
They're mentioned in the SVRaster paper.
https://svraster.github.io/images/teaser.jpg