Let me explain it with a clip of an ancient procedural generated game.
I chose this short clip because i restarted level 31 of the tower, as you see i enter a couple of numbers to rebuild exactly the level how i played it last time, in a next play it will look different never twice you will encounter the same level in this game except you enter exactly the same numbers on which it was generated.
The layout of the level, the location of enemies, the location of the items to find, the meaning of the items you find, the strength of enemies, my strengths everything is rebuild simply by the numbers i entered.
The game is pure generated he used no "patterns" to control at least a little the result of the procedural generation, the game is in this state as you see it unfinished and in the state he left it when mattel electronics closed in 1983.
It is buggy as hell since there is no control over the result, often especially magical items crash the game for "no reason", they can work in one play and they can fail in the next just because one number isn't the same.
The galaxy of FE2/FFE is build pretty much like the tower, imagine the region you see like a level of the tower and if you move through the map sectors will be generated one after the other (or a range of sectors which is equal to a level in the tower). Similar like the enemies and items you find and how they interact a stellar system is build.
I just liked to show off with this that it's not possible to change something once it is generated.
I can change the so called magic number, the base numbers i used to build the game. It will build it up different but the problem stays i have no real control over the result. Yes i can avoid numbers which lead often to errors such i could filter but exactly this will lead to patterns.
Like i pointed out above we have in Pioneer exactly the same problem with quite well populated systems which have a market but they have no starport and also some other mistakes caused simply by generation
If one digs a lttle deeper
the whole thing reaches back to a time when there was no special random generators (there was but it wasn't implemented in this console) which would have been needed because for software who does this there wasn't space enough.
the simpliest way is reflected in a quiz game from an even little older console, the infamous "RCA Studio 2", it uses by the way the same CPU as the intellivision.
they solved the leak of random number generation with a very simple trick.
i.e.:
1, 5, 3, 9, 0, 2, 8, 4, 6, 7
now add 1
2, 6, 4, 0, 1, 3, 9, 5, 7, 8
a new number is "drawn"
It's very obvious in this way and i guess after the third play i noticed the pattern .
All of the "RCA" games use this if numbers have to be drawn.
In a quiz it is very obvious but if you would generate something based on this it won't be so obvious.
Just imagine you are in a room you can't see what is in the other rooms you can reach you have to open the door and peep into it.
btw, a "rand" does pretty the same you can't really draw random numbers, same input number (seed) will always produce the same output number.
an old developers joke:
rand = 4
#this number was drawn by fair dice roll
it points exactly on this behave, same numbers lead to same numbers - always.
It didn't took long and some noticed (already in the '60s) that this behave can be used to generate a game, it was all textbased but it was favored and played by students for a long time.
The developer of "tower" was a huge fan of such procedural generated role playing and he simply liked to get that for a graphical role playing game.
But you can't control the result and he would have needed a little more time to fine tune it.
There are endless possibilities in this way and you can only avoid errors if you avoid certain numbers, combinations of or if you precode.
To get something like "Tower" you don't simply add 1 to a magical number you perform various arithmetic stuff with it, you can divide it multiply subtract or add.
You just do it always the same and this is called procedural.
To the example i can't change now simply i.e. my stamina because this will change the numbers below wich are named here, "ID" and "Password", any change in the numbers above will affect those numbers respectively vice versa.
Personally i managed it to step thre levels back but then my knowledge ends, i'm not the maths crack to derive the maths he used for it and to derive from that the original "magical number". I would have to know first which maths he used or would have to experience it, like i said i'm not the dude who could do such i guess.
For quite a while it kept me busy because i really liked to find out which maths he used.
As i pointed out in a sort of manual for this game (which else has no manual) this is the real mystery of the tower, it will make you to a victim to the tower.
You will be lost forever - har har
A little bit you can influence this but as more you do that as less generated it will be, so if Andy would change this or work out patterns which will avoid this (as far as you can get really totally rid of it, i doubt this) the systems would follow more given patterns. Also it would change all the systems you know from FFED3D completely.
This happens each time one compiles the source of "Pioneer", if you change in the source just a little it will build the galaxy different.
FE2/FFE has only a handful of pre-coded systems all the rest is generated. Even Some which have descriptions are pure generated systems, most of them.
So you see it would be a big fault to change anything on this because the descriptions and missions which are also relative to those systems wouldn't work anymore.
For Pioneer we can't have such missions which are bound to a generated system exactly because of that (except for the scripted and those which are imported from the Gliese star catalogue), but you can set factions and make missions relative to the faction no matter what systems are in this faction. The system where the faction originates from is only set by coordinates so it won't matter some system will match the coordinates and the system number usually it is "0" because in each sector is a system no. "0". If not which could be the case the faction won't be build. recently we generate a lot of them 99 if i'm right but scripted factions would be better because you can then depend on that they will be present always no matter if the galaxy is build different. In Phoenix which is Pioneer alpha31 i have no missions yet who are relative to factions but Pioneer itself is quite a little further and offers such i guess.
