LOD:
Some objects have LOD, stands for level of detail. What this meens is that you get farther away the shape changes to a less detail shape. The LOD slider modifies this distance when somthing changes.
Object Size :
As you get farther away from objects and polygons they shrink in size on the screen. This slider sets how many pixels and object or polygon must be to be displayed. Not this has no effect on player objects like vehicles and planes.
Ground Detail range. Groud detail is all the stuff you see in an empty terrain tile. i.e. no field or factory. There is a clipping plane ahead of your view. Ground detail behind that plane will not be displayed. The slider simply controls the distance of that clipping plane.
Textures to load per frame. This slider will not effect frame rate, but will effect sutters. It is simply how many textures can be loaded on any frame. Texture loads can be fairly time consuming, normaly after the intial start of the game texture loads happen as the texture comes into view, because this is normaly done at a disance you cant yet see the detail of the texture, making this setting 1 will be where most people will want it to be. Notice on start up how the textures come in 1 per frame untill the entire seen looks correct.
This setting does not effect textures that are used as windows, like your text buffer, and some windows that appear on the clip board.
HiTech