[2.0.23] Remote controlled spidertrons do not generate nests in generated but unexplored chunks

[Barblegarb]

1. What did you do?

Using a remote controlled spidertron, I walked along the edge of my map between explored and unexplored chunks. I used the debug menu [F4] with show-generated-chunks and show-enemy-expansion-candidate-chunks enabled, and followed the edge of explored chunks on my map. I destroyed all visible bug spawners and ventured into the generated-but-unrevealed chunks to destroy spawners that had been generated (and could therefore send out expansion parties) but not yet revealed.

2. What happened?

New spawners would show up in chunks that were revealed (visible), but *not* in generated (but unexplored) chunks. The upper left quadrant of my map shows this: https://i.imgur.com/YWILGMO.jpeg. The red to green circles show the enemy-expansion-candidate-chunks, and can originate from chunks that have been generated but not explored - they do not appear at all along the upper left quadrant where I used my remote-controlled spidertron to destroy spawners.

Here is another picture showing a group of spawners that was generated in an unrevealed chunk, then revealed using a remotely controlled spidertron: https://i.imgur.com/RfmuI1v.png. Note that despite the chunks to the left and right of the nest being completely generated and revealed, they are not treated as valid expansion candidates for bug nests - the only expansion candidates are those that were in previously revealed chunks.

3. What did you expect to happen

New spawners to show up in generated chunks, not just revealed chunks. In this picture: https://i.imgur.com/rvFkTZn.jpeg I walked my engineer near the edge of the map and new spawners were generated well before reaching the edge of the map. Pollution, radar, artillery shells, and players near unexplored chunks will generate new spawners outside visible range; remote controlled spidertrons will not.

This allows you to semi-permanently remove enemy spawners (and therefore enemies) from your map - as long as you keep your pollution cloud, radar, artillery shots, and players away from the explored edge of your map to prevent new spawners from generating in unrevealed chunks, you can completely remove enemies from gameplay.

4. Does it happen always, once, or sometimes?

It happens every time.

[Techjar]

This is a well-known thing that's been around for years. I believe it's considered a won't fix because Wube doesn't want to make radar coverage trigger chunk generation.

[Barblegarb]

But radar coverage does trigger chunk generation. In fact, every single action that reveals chunks will generate chunks + spawners - except for Spidertrons. That's why I figured it's a bug; it's the only method of exploration that allows you to completely clear a surface of enemies and spawners.

[Rseding91]

Thanks for the report however I'm unable to find any bug here. The underlying reason why you're seeing what you're seeing is 3 fold:

1. You're using debug options that show things you aren't normally meant to see unless you want to "cheat" and see them anyway.
2. You're using a late-game entity that can both kill things and chart the map near itself without generating far-away chunks
3. You're on a small map using (what I can only assume with no save file) - are spawned in late game entities - meaning the biter nests are relatively thin

Because spidertrons were designed to not generate far-away chunks (like the player and radars do), you're able to get close enough to existing nests using the (assumed spawned) spidertrons to kill them without generating additional chunks, and because it's such a small map area the nests are thin enough that they haven't generated on the nearby chunks forcing you to get even closer to the edge of the generated area.

All of these combined mean you can cheese the biters to your liking. But you could also just un-check the "enemies" checkbox at the start of the map to get the same effect if wanted.

[Barblegarb]

Thanks for the report however I'm unable to find any bug here. The underlying reason why you're seeing what you're seeing is 3 fold:

1. You're using debug options that show things you aren't normally meant to see unless you want to "cheat" and see them anyway.
2. You're using a late-game entity that can both kill things and chart the map near itself without generating far-away chunks
3. You're on a small map using (what I can only assume with no save file) - are spawned in late game entities - meaning the biter nests are relatively thin

Because spidertrons were designed to not generate far-away chunks (like the player and radars do), you're able to get close enough to existing nests using the (assumed spawned) spidertrons to kill them without generating additional chunks, and because it's such a small map area the nests are thin enough that they haven't generated on the nearby chunks forcing you to get even closer to the edge of the generated area.

All of these combined mean you can cheese the biters to your liking. But you could also just un-check the "enemies" checkbox at the start of the map to get the same effect if wanted.

The debug option isn't necessary, it just makes the process faster; explore ~6 chunks past the explored edge of your map and you can accomplish the same thing, because that's roughly the limit of chunk generation past the explored edge of the map by the player, radar, and artillery.

I attached my save. Yes spidertrons are late game, but nothing was spawned in - this is a save with several hundred hours, stock-standard normal Space Age gameplay, all default settings.

I wouldn't consider this a huge issue, just wanted to bring attention to it because it doesn't seem like Spidertrons should generate chunks differently than everything else. Beside that, this strikes me as an exploit - something that breaks game mechanics in a way that's probably unintended. Similar to how the ammonia rocket fuel recipe was recently patched to not allow an infinite solid fuel recycling loop.

If Spidertron chunk generation behavior is working as intended, then this is an unavoidable side effect. If that's the case though, just out of curiosity, why do spidertrons generate chunks differently than every other player-controlled entity?