I like this question. It really points out the difference between the 3D web page experience and the AR experience. I think that we, as 3D developers, have to think carefully about the AR experience that we build for our users.
When I use Verge3D on a web page, I can pan and zoom the scene. I can do this with touch or with a mouse. In this case, panning and zooming are moving the virtual camera. This user interaction does not change the size of the 3D object(s).
When I use Verge 3D in AR, I can pan and zoom the 3d scene by moving the phone or tablet that I and using to view the AR world. In my experience, Google AR services do a good job placing the 3D geometry into the real world at the scale at which they were drawn. For example, if were to draw a 1-meter cube in Blender, the AR system renders the cube at a scale that makes it appear to be 1-meter.
In the AR scenario, should we allow pinch-to-zoom? If we did, the pinch-to-zoom would be changing the scale of the 3D meshes. This is a different behavior that pinch-to-zoom in a webpage (where this gesture is interpreted as a dolly camera move). Maybe the answer is to build on-screen tap (not drag) controls that only appear in AR mode that explicitly affect the object scale?
These are just some ideas. This is not a criticism of the Verge3D system. AR is new and I think that we need to work on the user experience and establish some best practices. I am curious to see what solutions other users have tied to implement.
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