Linear shadow shader in ARSCNView.

Shadow makes 3D models more realistic.

In AR Quick Look, animated 3D model's shadow is really good. Because the shadow's transparent changes dynamically. I want to that feature in ARSCNView using shadow only material and shader.

I don't know about shader.
So please help or give some advise about linear shadow or shadow shader.

I did a question to WWDC20 SceneKit Lab, he told me to submit the post on the developer forum.
Linear shadow shader in ARSCNView.
 
 
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