From my understanding, and this is just purely observational data I gathered, it rolls engine, weapon and armour based off of base design, and then modifies it based off of structural design. Or at least, I think that is how it is supposed to work. I could be wrong though.
For the sake of complete understanding, I will use some numbers which I think are likely close to how it actually works.
BD = Base Design
SD = Structural Design
WD = Weapon Design
FP = Firepower
So let's say you put a 1000 FP gun on your whatever. You roll a new model and it has 110 SD and 100 BD. When it comes to rolling WD, I think it might be something in the range of +/-30 BD. I have seen it go as high as 28 in the positive direction.
(Addendum) In my other thread where I point out that field testing adjustment are not being used properly, I use this as a basis, because the actual values rolled are far below the +/- 30 I mention, which is otherwise consistent.
If we assume that the 30 roll range is accurate, then in our example, you might get super lucky and roll 130. With our 110 SD, I imagine it is 130 * 1.1, which puts it at 143. Your final FP is 1000 * 1.43: 1430. Which later gets modified for soft attack based on weapon type, attacks, etc.
In short, the WD, AD and ED values are always random. When you are making a model, you want to make something with high SD. You can fairly easily get high BD. It might even be a tactic to make really cheap units, throw them into battle, and then develop a new, OP version with proper weapons and armor and engine.
Hope this helps.
< Message edited by WeaverofBrokenThreads -- 6/12/2020 6:34:03 PM >