In this recipe, we will create a fake Subsurface Scattering material using the Translucent BSDF shader node as shown in the following screenshot:
The rendered result of the fake SSS of this recipe
As someone suggested, this material could actually be quite good to make candles.
Start Blender and open the 9931OS_07_start.blend file:
- Go to the Render window, and in the Sampling subpanel, click on the Method to sample lights and materials button to switch from Path Tracing to Branched Path Tracing. Enable the Square Samples item, and under AA Samples, set the Render value to
8. Finally, click on the Pattern button to select the Correlated Multi-Jitter item. - Save the file as
9931OS_SSS_translucent.blend.
Let's go ahead and create the material using the following steps:
- Select the Suzanne object and click on the New button in the Node Editor window toolbar, or in the Material window to the right. Rename the material
SSS_translucent. - In the Material window, switch the Diffuse BSDF shader with a Mix Shader node. In the first Shader slot, select a Diffuse BSDF shader again, and in the second slot, select a Glossy BSDF shader node.
- Set the Diffuse BSDF shader node's Color values for R to
0.031, G to0.800, and B to0.000. Set the Glossy BSDF node's Color values for R to0.646, G to0.800, and B to0.267. Set the Glossy BSDF node's Roughness value to0.200and Distribution to Beckmann. - Select the Mix Shader node and go to the Properties side-panel of the Node Editor window (if not present, move the mouse to the Node Editor window and press the N key to make it appear). In the Label slot inside the Node subpanel, label the Mix Shader node as
Mix Shader1. Then set its Fac value to0.200. - Add a new Mix Shader node (press Shift + A and navigate to Shader | Mix Shader), label it as
Mix Shader2, and paste it between the Mix Shader1 node and the Material Output node. - Add a Translucent BSDF node (press Shift + A and navigate to Shader | Translucent BSDF) and connect it to the second Shader input socket of the Mix Shader2 node. Set the Color values of R to
0.800, G to0.086, and B to0.317. - Add a Texture Coordinate node (press Shift + A and navigate to Input | Texture Coordinate), a Mapping node (press Shift + A and navigate to Vector | Mapping), and a Noise Texture node (press Shift + A and navigate to Texture | Noise Texture).
- Connect the UV output of the Texture Coordinate node to the Vector input socket of the Mapping node, and the output of this node to the Vector input socket of the Noise Texture node. Set the Noise Texture node's Scale value to
20.000. - Add a Bump node (press Shift + A and navigate to Vector | Bump) and connect the Color output of the Noise Texture node to the Height input socket of the Bump node. Then connect the Normal output of this node to the Normal input sockets of the Diffuse BSDF, Glossy BSDF, and Translucent BSDF nodes. Leave the Bump strength at
1.000. - Add a Fresnel node (press Shift + A and navigate to Input | Fresnel) and connect it to the Fac input socket of the Mix Shader2 node. Set the IOR value to
8.000as shown in the following screenshot:
The overall view of the material network
- Save the file.
This is probably the simpler form of the fake Subsurface Scattering effect you can get in Cycles. It is obtained by simply blending a translucent effect with a basic Diffuse-Glossy shader. By varying the amount of the IOR value in the Fresnel node (set quite high as a starting point), it is possible to establish the amount of translucency on the mesh. We also added a Noise Texture bump effect to the material, just to make it appear more jelly-like.
Note that we gave almost complementary colors to the Diffuse BSDF and Translucent BSDF shaders to show the effect more clearly, but colors similar to each other can work better. Also note that the translucent effect actually follows the direction of the lighting. Try to rotate the Emitter and the Emitter_back planes around the Suzanne mesh to verify this in real time, through the Rendered view as shown in the following screenshot:
A preview of the fake SSS material lit from a different angle