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Gregory Abbey
August 12th 04, 07:06 PM
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..?

-Gregory

deimos
August 12th 04, 10:05 PM
Gregory Abbey wrote:
> 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..?
>
> -Gregory
>

Without any mipmaps (pregenerated or otherwise), you're going to see
aliasing as the angle of the apparent terrain/horizon decreases. This
is the result of linear interpolation without any sub-textures (mipmaps).

I'm not too familiar with the development aspects of FSim, but hopefully
the game supports pregenerated mipmaps. These would normally be made as
a subset of the original texture at a decrease power of 2 resolution
(i.e. 256 -> 128 -> 64... onward).

Without mipmaps, the texture aliasing can be misinterpreted as added
detail or "sharpness", but it's not.

Also, unless a game is specifically written for that version of DirectX,
you'll only see any ancillary benefits (like code cleanup, better
texture management, new shaders, etc).