Vision origin of binding change

In perspective, you can write script change events on particular properties to only trigger based on origin of change. Is this achievable in vision?

No, not directly, as that was a new feature for Perspective.

For Vision input fields, a close approximation can be achieved by splitting off an original, perhaps bidirectional, binding to a custom property, then unidirectional binding the input field's value property to the new custom property. Then in a change event script on the value property, the new value can be compared against the custom property. If equal, the value likely came from the binding on the custom prop. Otherwise, you can be sure it came from user input.