I had done something like this many years ago but had until just, completely forgotten about the technique

Here are some example's I've made of volume like rendering, done simply by duplicating a sphere 200 times inside itself smaller and smaller. The volume can be controlled by 3D noise shaders and gradients. And also by Proximal shader where by it shades based on distance to another object.

The following are controlled by shaders, 3D noise shaders and 3D gradients, you could also use Proximal shader to control the shading based on distance to another object.

Imagine being able to make them reflective/shiny sub surface scattered and render fast... that would require true volumetric rendering I think

Also I don't fancy trying to cast shadows or use GI on these things... it my explode and look bad to boot.

It's a bit of a tangent from the normal Vray/C4D use for sure. Someone could go to all sorts of lengths writing shaders to mask based on the volume of other objects, say in order to boolean a volume with another object, but it would boolean inside the shader volume no polygonal operation. And controls for feathering that and so on. 3D falloff/feather/blend controls... could go on and on. Just my fantasy here *drewls*

I wonder if a particle/fluid based volume rendering system like Mayas or Houdini's could be contorted to do this kind of thing, to have the same kind of controls or better. That may be the answer. It should be easier more practical to twist a real volume/fluid/particle solution into doing this, than to twist a 3D shader to do it, plus you'd then get the benefits of being able to do fluid like effects on it and have it interact with other objects in ways a 3D shader never could. I think the biggest problem with using fluid/volume renderer to do it is the resolution, they tend to be very veeeery slow at anything but the fuzziest resolution.








No Cubes here, just 200 Spheres + 3D Box Noise shader... honest













Made from light, the color becomes additive, though It's not quite right, the colors will flatten, they won't additive to white, which sucks.
Wait, no that's just me being stupid, you need the colors to be greater than 100% bright for that...



Tadda made from light take 2:


Cinemas gradients cannot go above 100% brightness, they are 8bit essentially, however you can multiply them up, by overlaying a super bright white layer and setting it to multiply.


Problem with this is, due to it being made from onion skins, the sides are not additive as they are not perpendicular to the camera, so where the edges should get brighter, they do not.

To solve this I tried rendering a few 100 planes stacked in front of each other facing the camera, and using a 3D spherical gradient to make it look like a hemisphere:

ooh, looks good, but won't work right if rendered from above:

In theory you could have the planes orinet to face the camera at all times, as the shape is entirely controlled by the shader.


Nice!

I also tried making it out of Cubes, but it was too slow and looked bad: