I guess there are few options. Maybe the easiest would be to have some blocks prebuilt and just place them next to each other. In the simplest case you could create templates for those blocks, and a block could have terrain, grass, rigidbody). And you just add them netx to each other at the start of the level / as you go.
Thanks @will, so it is possible to create game like this…
Thanks @mvaligursky, so mesh generation is only the way to this? i have to do research on it then… anyway i will look at this later…
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So far i manage to place car on box shape track… (So it could look like 2d)
To prevent movement or rotation in an axis just set the the Linear/Angular factors to 0. For example this body can’t move on the Y axis and can’t rotate around X and Z: