In 3D we can already request the viewing angle so that billboards can be rotated into the right view towards the user.
We need the same thing for sections and elevations.
What do we need that for:
- billboards that work everywhere
- hiding/showing details depending on the view direction (e.g. think of doorframes which look horrible in sections > 1:50 where the door is not perpendicular to the viewing direction)
- etc.