[2.0.34] Non-deterministic chunk population with trees over ores during map generation

[Data]

What did you do?

• Run Factorio 2.0.34, base game without mods and without Space age DLC
• Single Player > New Game > Freeplay
• Set seed to 2953497924 (any seed will work, but you need to find an ore patch with trees over it outside pre-generated area and teleport to it instead)
• Start the game with default settings
• Run the command (twice to suppress achievements disable warning):

  Code: Select all

  /c game.player.character.teleport({-50,-375})

• Observe how trees are placed over ores, record the observation
• Repeat all these steps few times

What happened?
Trees generated over ores have different count and placement configuration (see attached screenshot for example)

What did you expect to happen instead?
Each time same number of trees placed at the same spots

Does it happen always, once, or sometimes?
Sometimes

Screenshot 2025-02-11 224308.png (4.5 MiB) Viewed 327 times

Screenshot 2025-02-11 224248.png (4.54 MiB) Viewed 327 times

[boskid]

I have a feeling this bug report may be effectively a duplicate of 87106. Near the beginning when chunks are still generated, if you teleport to that position it is possible just by changing exact tick at which you teleport, you may get different order of chunks generated because of existing chunk generate requests vs new chunk generate request due to character teleport. When i did some experiments i was using a console command that teleports character always at the same tick and the outcome was always the same. If chunks generation order is different then there may be some entities on the chunk boundary that are colliding with a nearby chunk (where in opposite generate order, neighbour would still be empty) and when some entities are not spawned they may cause random generator to not be pushed forward causing an observable difference in entities placement. I will keep this in bug reports until it gets verified to be exactly that behavior but i do not predict this would be anything important to be fixed, most likely will get moved to duplicates.

[Rseding91]

Moving to duplicates as I don't see a solution here that wouldn't have undesirable side effects.