so really all you want to do is take the matrix
X Y ... and use a Bitmap X Y for the track collision right?
what your really asking for here is interpolated spline collision - where you give it points based on the bitmap and it will calculate the collision based on those points, either with a Bezier Curve calculation or with Standard Corners... that would be kinda tricky to accomplish - however i can see how i'd be a great advantage

wouldn't have thought of doing it that way myself hehee
so what you really need is an array which precompiles before the world is inililised.
that would store the points for each of the tile types, splines, points to calculate
so like
dim ptrTileSplines(Tiles,Splines,Points) as Vec2
dim ptrMatrixCollision(TileX,TileY,2)
1 is the tile texture matchs the TileSpline (used for the calculate) and 2 is for the Angle it is.
i'm not so sure about spline maths but its pretty standard Algebra Trignometry from point-to-point
you don't need the Y value for height as you can use just the get matrix height ... and if you do that for each wheel you can calculate the tilt of the vehicle
if i can find my pencil i'll jot down alot the calculations cause its easier to understand them witha diagram
Tsu'va Oni Ni Jyuuko Fiori Sei Tau!
One block follows the suit ... the whole suit of blocks is the path ... what have you found?