Update
Added Rolling Resistance/Friction force as a part of Anisotropic Friction Component functionality. In Settings->ProjectSettings->Physics->PhysicalSurface we can define a number of the EPhysicalSurface records that can be later used in physics materials to make it very simple to understand what kind of physics material we are dealing with and how should we react to it. For example, by spawning different particle effects when something hits them or changing decals for the tank tracks:
Type of the Physical Surface can be read on collision hit events or on raycheck test. For landscapes, you can set physical materials (bound to one of the EPhysical Surface types) in information layer assets.
Now we can define a set of Rolling Resistance/Friction coefficient for each EPhysical Surface in Anisotropic Friction component:
This allows to tune how fast our vehicle should be moving on different surfaces, like tarmak, concrete, dirt, snow or any other type of surface that you want to have in your game.
Landscape deformation now have a different amount of displacement depending on the paint layer, each paint layer can have a different physical material assigned to it and in combination with binding to EPhysical Surface you can have different particles spawned or physics behavior on different materials. Here you can see that deformation from tracks is deeper on sand than on rocks:
