There’s nothing built in but you can just transform the world coordinates by the inverse of the body’s world matrix. The begining of these two videos have a very good explanation on coordinate systems transformations: Camera/View Space // OpenGL Beginners Series - YouTube
3D Software Rendering Graphics Pipeline - YouTube
About the PointerDragBehavior, you can simulate drag using the start and releaseDrag methods: PointerDragBehavior | Babylon.js Documentation (babylonjs.com)