Thomas Leitner
Member
I did some tests on a very specific problem. Here are the results and the method (maybe someone could use that, too):
Since you have to do the fractureing already in Modeler and not on the fly in Layout, there is a problem when rendering materials like porcelain, which absolutely need sub surface scattering. You can see the fracture lines shining through.
Before breaking, you can simply exchange the object for a whole object. But with the first fracture, the fracture lines appear on the entire object. This ruins the effect of larger pieces breaking into smaller ones.
To avoid this I chose the following method, which works for this task, even if there are some inconsistencies (maybe for me only).
For the material of the edge I used a clip map which is controlled by a gradiant. This has as input the length output of the Ray Trace Node. The idea behind this is: for each point, it is looked at how far away the nearest geometry is and thus determined whether the edge is visible to the camera or is still hidden in the object. If it is still hidden in the object it will be clipped by the clip map and it cannot cause shadows in the sub surface scattering of the porcelain. I hope that makes sense.
Perhaps one of the node experts knows a better method or improvments.
The Gif do not show the material correct, look at the pictures above.
A few more things about the porcelain material: To have a little dirt in the depressions, I use the "Patina" node. I use it to control color and roughness. To save render times I have rendered the “dirt texture” (Dirt output of the Patina node) as an image with the surface baking camera and used it instead to control color and roughness.
The rest is a simple Principled BSDF material with little roughness and lots of sub surface scattering.
ciao
Thomas
Since you have to do the fractureing already in Modeler and not on the fly in Layout, there is a problem when rendering materials like porcelain, which absolutely need sub surface scattering. You can see the fracture lines shining through.
Before breaking, you can simply exchange the object for a whole object. But with the first fracture, the fracture lines appear on the entire object. This ruins the effect of larger pieces breaking into smaller ones.
To avoid this I chose the following method, which works for this task, even if there are some inconsistencies (maybe for me only).
For the material of the edge I used a clip map which is controlled by a gradiant. This has as input the length output of the Ray Trace Node. The idea behind this is: for each point, it is looked at how far away the nearest geometry is and thus determined whether the edge is visible to the camera or is still hidden in the object. If it is still hidden in the object it will be clipped by the clip map and it cannot cause shadows in the sub surface scattering of the porcelain. I hope that makes sense.
Perhaps one of the node experts knows a better method or improvments.
The Gif do not show the material correct, look at the pictures above.
A few more things about the porcelain material: To have a little dirt in the depressions, I use the "Patina" node. I use it to control color and roughness. To save render times I have rendered the “dirt texture” (Dirt output of the Patina node) as an image with the surface baking camera and used it instead to control color and roughness.
The rest is a simple Principled BSDF material with little roughness and lots of sub surface scattering.
ciao
Thomas
Last edited:
