I was looking for a rule or study that could help define how one would design text for a vehicle wrap. I've noticed that some wrap a vehicle based on the vehicle's contours but some wraps' designs are based on a level horizon.
For example this van below, even though the graphic is small, it is wrapped level:
However, when you look at this vehicle wrap the typography follows the vehicle's contour:
I understand that it may depend on vehicle but what I am after is how the design should be considered. Is there a study that indicates typography on a vehicle in movement has a better chance of being seen when based on the horizon? Is there a justifiable reason that typography on a vehicle should follow the contour other than it is aesthetically pleasing to one's eye?