Have downloaded DX90c for use 44.03 drivers in FlightSim.. and it
appears to make a significant difference.. in what one poster coined
as managing `AutoGen mips'.. which is essentially the resolution of
each terrain cell [texture] and it transition into the adjacent cell.
With mips turned OFF.. I'm seeing a reduction in `shimmering'.. and
also.. a general increase in TERRAIN_EXTENDED_RADIUS is possible.
What are the specifics of DX90c and how can the scenery be optimised
to take best advantage of it..?