I cannot for the life of me figure out how to get Cinema 4D noise shaders to working inside basic glass. For example, let's say you are making a basic marble (the sphere variety that kids play with, not the stone).
You start with a sphere and place on it a basic Corona Physical Material with the following changes from default:
Base Layer - Roughness value is changed from 75% to 0%
Turn on Rerfraction - (no changes to defaults)
OK, we now have a simple glass sphere. Now, the goal is to get a 3D Cinema 4D Noise shader inside the glass and not just on its surface.
I will be using the following Noise Shader and settings for this task:
Noise: Hama
Color 1: Pure Black (RGB: 0,0,0) (Should be the default)
Color 2: Pure White (RGB: 255,255,255) (Should be the default)
Space: Object
High Clip: 5% (To make the lines sharp and well defined, helping us determine whether they are on the surface or actually inside the object)
Everything else set to the default
OK, now if I stick the above Shader into the Refraction texture, I get noise on the surface of the glass sphere and not inside of it. This is true regardless of the Space property inside the shader (I tried them all going one by one from UV-2D to raster, and Object is the correct setting for 3d noise, so I settled on that).
Lesson learned: Putting a 3d noise shader into the Refraction texture slot only affects the surface of the object (i.e., sphere) and not its inside
Then, I tried to see if maybe turning on Volumetrics and placing that same Shader into the Absorption Color Texture slot would cause the inside volume of the sphere to take on the noise. (Mix mode was left at Normal and mix strength at 100%. The color was left at a default of 50% gray and is disabled in any case when the Texture slot is filled).
There was no change, the noise only affected the outside of the sphere and the result is attached.
I can't for the life of me figure out how to get the noise to appear, in 3D inside the sphere and not just on its surface.