I am making a game where I need a car to be able to drive on the ceiling of a tunnel.
The world settings have an option for overriding the Global Gravity Z but it is my understanding that this value can not be changed programmatically via blueprint so I tried using an AddForce node with the value of -980 multiplied by the mass of the car in the z-axis and disabling the gravity on the car. This would allow me to programmatically invert the gravity when I need to. -980 is the default gravity z value so this should affect the car the same way gravity did. However, This caused some really strange behaviour. The car fell to the ground like it did with gravity but it did not seem to be affected by friction. It was sliding like it fell on ice and the wheels just spun.
Why does the force affect the car differently than the global gravity did?
Is there an alternative way to achieve the desired behaviour?
Assuming cars use the same mechanic as characters do to locate a ground its on, it is most likely only looking in the negative Z direction and not up. So the car probably doesn’t think its supposed to be driving on the ceiling.
Keep in mind this is speculation though so I could be completely wrong 