snap
Requests a snap against an element of this asset.
A view-correct world-to-view matrix is composed from options.camera, options.canvasWidth, and options.canvasHeight so view-dependent snapping (nearest ordering, pixel apertures, surface tracking) matches the current view.
Only 3D views are supported: the camera must be viewing in SceneMode.SCENE3D.
Return
The snap result, or undefined if the element was not found or no snap was possible for it.