In Freelancer asteroid fields are made of repeating cubes which fit into whatever shape the asteroid zone is (typically ellipsoid), these cube patterns are filled with individual asteroid objects arranged inside. Optionally these pattern cubes may have randomization such as rate of empty blocks that will be skipped, rotation (which is what you see on the picture). This is why if you fly in straight axis inside some asteroid fields that have no rotation randomization you'll eventually notice same pattern of asteroid over and over again (for example in Cortez it's the field around California gate, Omicron Kappa and various other places). These cube patterns have size property, so if you increase the size of the cube the asteroids within will be sparsely arranged and if you decrease size the field will be quite dense. Which is quite nice for a system designer to quickly adjust fields to be either more capital ship friendly or the opposite. But what are the limits? While very large sizes are possible I had found one big issue - after pattern cube exceeds certain size the individual asteroids within will have their hitboxes disabled for some reason (I suspect it's a hardcoded limit related to collision physics optimization), all except one that has to be located directly in center of the pattern cube. Another limitation is that one asteroid field may use only one material for asteroids within it. It's a very strange limitation but it is there, so if say if you'll try to have a single asteroid field to use two different asteroid types each with their own texture in the resulting field they'll all have one texture regardless. The solution of course is to use atlas textures: basically images that simply contain different textures within. But it's not all that easy - you can't tile atlas textures as it's no longer seamless uniform texture so UV mapping of meshes has to be done very carefully as well. As a matter of fact it's how debris fields in Texas are made. The other solution would be to use several overlapping fields because unlike nebula fields these can intersect just fine.
Static asteroid fields is a very interesting feature of Freelancer engine, it has simple mechanics and I think there many more uses to it other than its intended purpose, some of which you'll see in omicrons update and I hope you'll like them.
