Using dSetInternalSpaceCollideMode(0) only affects collisions of objects within the same sub-space, so as long as you don't put your vehicles in the same sub-space as the static scenery, the collisions & detection will still work as expected.
Although using dSetInternalSpaceCollideMode(0) won't affect the collision detection, using multiple spaces does. You need to use both the dGeomCountCollisions(geom) function and also the dSubGeomCountCollisions(geom) function to detect all possible collisions. Check out the 'CarDemo-DetailedC-MS.bb' demo to see this in action.
Basically, you just need to do this...
TotalCollisions = dGeomCountCollisions(WGeom(count)) + dSubGeomCountCollisions(WGeom(count))
You can also find more info about these functions in the JV-ODE Function Reference.
Although using dSetInternalSpaceCollideMode(0) won't affect the collision detection, using multiple spaces does. You need to use both the dGeomCountCollisions(geom) function and also the dSubGeomCountCollisions(geom) function to detect all possible collisions. Check out the 'CarDemo-DetailedC-MS.bb' demo to see this in action.
Basically, you just need to do this...
TotalCollisions = dGeomCountCollisions(WGeom(count)) + dSubGeomCountCollisions(WGeom(count))
You can also find more info about these functions in the JV-ODE Function Reference.