NFS Underground was designed in 'chunks'..
A whole city was modelled, and the tracks designed around certain routes. As you've no doubt noticed NFS U. has a very high polycount, thats because your limited as to what track (or part of city) you can drive around in..
Whereas GTA 3 is 'freeflow' (you get to go whereever you want).. but at the price of a low'ish polycount.
Your best bet... or the way I'd do it - design the whole city/level in a 3d package, and split it into sections.
1 complete mesh/object for each section
That way you'd only have to use the certain sections you want for that race, and have the added bonus of being able to hide away sections that cant be seen.
But, YES it is possible..
[edit] rereading your post you wanted to do early nfs track which where more 'open'.. but its the same principle as above.
A whole city was modelled, and the tracks designed around certain routes. As you've no doubt noticed NFS U. has a very high polycount, thats because your limited as to what track (or part of city) you can drive around in..
Whereas GTA 3 is 'freeflow' (you get to go whereever you want).. but at the price of a low'ish polycount.
Your best bet... or the way I'd do it - design the whole city/level in a 3d package, and split it into sections.
1 complete mesh/object for each section
That way you'd only have to use the certain sections you want for that race, and have the added bonus of being able to hide away sections that cant be seen.
But, YES it is possible..
[edit] rereading your post you wanted to do early nfs track which where more 'open'.. but its the same principle as above.