AR - Draw on a virtual 3D object

Hello everyone,

I'm working on an AR app. There I load a 3D model of an human arm and place it on a QR code (ARImageAnchor). The user can now move the model and change its texture.

Is it possible to draw on this 3D model with my finger? I have seen videos where models react to a touch. But I don't just want to touch the model, I want to create a small sphere exactly at the point where I touch the model, for example.

I would like to be able to draw a line on the arm. My model has a CollisionShape.

AR - Draw on a virtual 3D object
 
 
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