A tool that when activated would radiate a shaded circle from your cursor indicating a persons vision. This circle radius can be adjusted based on view distance.
When hovering over the plan walls would obstruct this circle allowing you to see what people can view. Moving it around would adjust the sightlines.
In the design phases the tool can be used to help visualize important views as a person moves through a series of spaces. In more technical phases this is helpful when creating restroom or locker room entrances and you want to avoid people in the adjacent spaces seeing in.
For an example of something similar see the below link.
Can't find what you're looking for? Ask the community or share your knowledge.