Well if it's not as fast as you would like, why not generating bigger tiles, in much lower res, then when you get close you fake tesselation with :
First you have the min res tiles, when you get closer
You tween3dAlpha them down, and tween3DAlpha up the higer res ones.
Edit: these 2 tweens need to start and end together for the effect to take place.
This could be done quite easily and you can get huge amount of correct landscape that way.
Just dont forget to setobjectvisible(lowTerr,0)
So you actually get the same draw calls.
And also use a distance fog shader, which will eliminate all the basic looking min res terrain "errors" , meaning the lower res just wont be noticeable as lower res.
Nadav "Haliop" Rosenberg
Lets make the world great forever.