In Spark AR Studio, you'd use an occluder to make an AR scene more realistic, by hiding things that would be hidden in real life. They're particularly useful when you're layering 3D objects on someone's face.
Occluders are made of an object with a material applied to it. You can create the material in Spark AR Studio.
Use occluders to hide things that wouldn't be visible in real life.
For example, in the image on the left there's no occluder. The arm of the glasses is visible when it should be hidden by the head.
On the right, we've added an occluder that covers the face. The arm of the glasses is no longer visible through the head:
Any 3D object can be used as an occluder.
If you're occluding the face, use a face mesh. This will cover the face and respond to its movements.
If you want to occlude the volume of the entire head, you can use the head occluder object that's included in the Spark AR Studio face references assets.
Once you've created a material, in the Inspector change:
The material will be transparent, but still hide objects behind it.
In the material's properties, you might want to check the box for Double Sided. For example, so the back of the face mesh is also occluded if the user turns their head to the side.