[0.16.17] Map Exchange string does not produce same map

[DRY411S]

Steps to reproduce:

1. Generate map in 0.15 (an island) using this string
   String used to generate 0.15 map

   Code: Select all

   >>>AAAPACgAAAABBQcAAAAEAAAAY29hbAMFBQoAAABjb3BwZXItb3Jl
   AwUFCQAAAGNydWRlLW9pbAQFBQoAAABlbmVteS1iYXNlAQEFCAAAAGl
   yb24tb3JlAwUFBQAAAHN0b25lAwUFCwAAAHVyYW5pdW0tb3JlAwUFdK
   18lICEHgCAhB4ABAABAQF7FK5H4XqUPwEAAAAAAAAuQAEAAAAAAADwP
   wEAAAAAAFi7QAEAAAAAAOCFQAEAAAAAAFirQAEAAAAAAIjDQAEAAAAA
   AECfQAEAAAAAAEB/QAEAAAAAAECPQAEzMzMzMzPzPwEzMzMzMzPzPwF
   7FK5H4Xp0PwEAAQAAAAAAAAhAAQAAAAAAAAhAAXsUrkfheoQ/AQABAQ
   GN7bWg98bQPgH8qfHSTWJgPwFpHVVNEHXvPgEBAQcAAAABAgAAAAECA
   AAAAZqZmZmZmbk/AQAAAAAAAABAAQAAAAAAAOA/AZqZmZmZmdk/Ac3M
   zMzMzOw/AQUAAAABFAAAAAFAOAAAAcBLAwABEA4AAAGgjAAAASAcAAA
   BAAAAAAAAPkABAAAAAAAAFEABZmZmZmZm9j8BMzMzMzMz4z8BMzMzMz
   Mz0z8BAAAAAAAACEABAAAAAAAAJEABPAAAAAEeAAAAAcgAAAABBQAAA
   AEAAAAAAAAAQAEBAQAAAAAAAFlAAQUAAAABGQAAAAEAAAAAAAAkQAEy
   AAAAAQAAAAAAAD5AAWQAAAABmpmZmZmZyT8BMzMzMzMzwz8BMzMzMzM
   z0z8BMzMzMzMz0z8BAAAAAAAAJEABAAAAAAAANEABAAAAAAAAPkABAA
   AAAAAAFEABAAAAAAAAPkABAAAAAAAAJEABAAAAAAAACEABCgAAAAFkA
   AAAAWQAAAAB6AMAAAEAAAAAAADgPwHQBwAAAQAAAAAAQH9AAwAAAAAA
   AAAAAAAA8D8jkoIH<<<

2. Save the map in 0.15
3. Load the saved 0.15 map into 0.16
4. It is the correct size and shape
5. Save it in 0.16
6. Get map exchange string from the 0.16 save
7. Use it to generate a new 0.16 map
8. Map is not the same as the previous 0.16 save

[Klonan]

Unfortunately, map exchange strings are not forward compatible,
So I would say, that this is not a bug,
Especially as the whole terrain generation changed between the major versions

[DRY411S]

I'm not expecting the map exchange string to be forwards compatible.

I'm expecting that if I save a map in 0.16, then get the map exchange string from the 0.16 save and use it to generate a new 0.16 map, then the map will be the same.

In this use case above, it's not.

I'm NOT saying that if I get a map exchange string from a 0.15 file and paste it into 0.16, then I'd expect the map to be the same. I wouldn't.

[Jap2.0]

The map exchange string defines the generation seed and settings. You generated the map using the 0.15 map gen. Generating it in 0.16 will give you somethinf different. Updating doesn't give a different string. In fact, it would be difficult to get the same result considering that terrain completley changed.

[DRY411S]

The map exchange string defines the generation seed and settings. You generated the map using the 0.15 map gen. Generating it in 0.16 will give you somethinf different. Updating doesn't give a different string. In fact, it would be difficult to get the same result considering that terrain completley changed.

I'm NOT generating a map in 0.16 using the string from the 0.15 map

I'm obviously not explaining this well.

I'm generating the map in 0.15 and saving the map in 0.15
THEN I'm loading the 0.15 map in 0.16 and saving in 0.16
If I look at the string in 0.16 save, it's completely different
That's what I would expect

It's when I take the string from the 0.16 save and use it to generate another 0.16 map, I get a different map. That's NOT what I would expect.

It doesn't happen with any map that is originally generated in 0.16. Generate map in 0.16 use the seed, get the same map.
Generate a map in 0.15, load and save THE MAP in 0.16 to save the file format to 0.16. See how the string has changed (as expected). Use the string to generate a new 0.16. Different map.

[Jap2.0]

The map exchange string defines the generation seed and settings. You generated the map using the 0.15 map gen. Generating it in 0.16 will give you somethinf different. Updating doesn't give a different string. In fact, it would be difficult to get the same result considering that terrain completley changed.

I'm NOT generating a map in 0.16 using the string from the 0.15 map

I'm obviously not explaining this well.

I'm generating the map in 0.15 and saving the map in 0.15
THEN I'm loading the 0.15 map in 0.16 and saving in 0.16
If I look at the string in 0.16 save, it's completely different
That's what I would expect

It's when I take the string from the 0.16 save and use it to generate another 0.16 map, I get a different map.

I know. The map generation changed between versions, so you cannot generate a map in 0.16 that is identical to a map from 0.15.

[DRY411S]

I know. The map generation changed between versions, so you cannot generate a map in 0.16 that is identical to a map from 0.15.

But I've saved the map in 0.16 to regenerate the string in 0.16 format?

If that isn't going to work, then I'd suggest that the game IS bugged in the sense that it should not display the string, it should display a message that tells you the string cannot be used to make the same map.

[Jap2.0]

I know. The map generation changed between versions, so you cannot generate a map in 0.16 that is identical to a map from 0.15.

But I've saved the map in 0.16 to regenerate the string in 0.16 format?

If that isn't going to work, then I'd suggest that the game IS bugged in the sense that it should not display the string, it should display a message that tells you the string cannot be used to make the same map.

No - the map was generated with the 0.15 generator, and it's giving you a string to make it work with that - which is also the string that is used to generate portions of the map that are unexpored when you update. The map generator was significantly changed, so it would be difficult, if not impossible, to find a string to generate the same map, which would also suffer from problems such as new terrain types, cliffs, etc.

[Zavian]

I know. The map generation changed between versions, so you cannot generate a map in 0.16 that is identical to a map from 0.15.

But I've saved the map in 0.16 to regenerate the string in 0.16 format?

If that isn't going to work, then I'd suggest that the game IS bugged in the sense that it should not display the string, it should display a message that tells you the string cannot be used to make the same map.

I'm pretty sure that all the map exchange string stores is the map settings (possibly including some extra settings that we can't access through he gui), and the seed. Loading and saving the map in 0.16 might give you a string that will re-apply the same map settings, and the same seed, but it doesn't change the fact that the actual code that generates the map has changed, and the new code has no idea how to generate a map that looks like a 0.15 map.

[DRY411S]

No - the map was generated with the 0.15 generator, and it's giving you a string to make it work with that - which is also the string that is used to generate portions of the map that are unexpored when you update. The map generator was significantly changed, so it would be difficult, if not impossible, to find a string to generate the same map, which would also suffer from problems such as new terrain types, cliffs, etc.

Yes I understand. And now that I do, I assert that it is egregious to have a map exchange string in the 0.16 file in the circumstances when the file has been converted from 0.15 to 0.16 by the game. It sets unfulfilled expectations. If I see an exchange string in a file, I expect it to generate the same map when I use it.

So not the original bug I reported, but IMO a bug all the same.

[Tekky]

I agree that this can be confusing. Maybe Factorio should provide some kind of warning when presenting the map exchange string, if the game was started using a different terrain generator.