Summary
Aender terrain was observed once with large chunk-aligned gaps and flat vertical cut faces after travelling back and forth through an Aender portal. The problem could not be reproduced in subsequent attempts, so this is an unconfirmed potential bug rather than a confirmed regression.
Environment
- Retold:
0.2.0
- Minecraft:
26.2
- NeoForge:
26.2.0.7-beta
- Inspected revision:
b49dae1
Observed behavior
After repeated cross-dimension portal travel, visible parts of several Aender islands ended abruptly at chunk-aligned vertical planes, with neighboring terrain columns apparently absent. The result looked like incompatible or missing chunks rather than normal floating-island shaping.
A screenshot was captured during the occurrence, but the behavior is no longer reproducible.
Expected behavior
Unstabilized Aender terrain may intentionally change after the last player leaves the dimension, but all chunks belonging to the new reality should be generated coherently without hard chunk-border cuts or missing terrain columns.
Attempted reproduction
- Reach Stage 3.
- Use the horizontal Aender portal between the Overworld and Aender.
- Travel back and forth repeatedly, including rapid re-entry.
- Inspect the surrounding Aender chunks.
The original occurrence happened during this kind of travel. Repeating the steps afterward did not reproduce it.
Potential cause (unconfirmed)
There may be a race between asynchronous portal destination generation and the dimension-empty reality reset:
AenderPortalWarmup adds a portal ticket that loads/generates destination chunks asynchronously.AenderWorldTickEvents.resetVolatileTerrain() calls AenderVolatility.clearForgottenWorld() as soon as the last player leaves.clearForgottenWorld() replaces the global reality salt/epoch and clears cached generation signatures.- A single
AenderIslandSampler.islandsForChunk() pass obtains individual region seeds through repeated AenderVolatility.islandSeed() calls rather than using an immutable per-generation reality snapshot.
- If the reset occurs while a chunk is still generating, that chunk could theoretically sample both the old and new reality.
AenderChunkGenerator.generateChunk() then calls markGenerated() using the current epoch, potentially marking a mixed chunk as current and preventing later stale-chunk repair.
This theory has not been demonstrated with logging or a deterministic test. A client chunk-packet/render desynchronization remains another possibility; it was not confirmed whether F3+A would have repaired the visual or whether collision matched the gaps.
Relevant code
AenderPortalWarmup.tickAenderWorldTickEvents.resetVolatileTerrainAenderVolatility.clearForgottenWorldAenderIslandSampler.islandsForChunkAenderChunkGenerator.generateChunkAenderRealityTickEvents.prepareArrivalView
Suggested investigation
- Log the reality epoch at the start and end of each asynchronous generation pass.
- Detect or retry generation if the epoch changes during the pass.
- Verify whether any portal-ticket worldgen tasks remain active when the dimension-empty reset runs.
- During a future occurrence, test
F3+A, collision, and server-side block state to distinguish render desync from mixed server terrain.
- Exercise rapid re-entry with high view distance in singleplayer and on a dedicated server.
- Add a test capable of overlapping generation with a reality reset; the current sequential regeneration GameTest does not cover this lifecycle.
Status
Potential bug / needs reproduction.
Summary
Aender terrain was observed once with large chunk-aligned gaps and flat vertical cut faces after travelling back and forth through an Aender portal. The problem could not be reproduced in subsequent attempts, so this is an unconfirmed potential bug rather than a confirmed regression.
Environment
0.2.026.226.2.0.7-betab49dae1Observed behavior
After repeated cross-dimension portal travel, visible parts of several Aender islands ended abruptly at chunk-aligned vertical planes, with neighboring terrain columns apparently absent. The result looked like incompatible or missing chunks rather than normal floating-island shaping.
A screenshot was captured during the occurrence, but the behavior is no longer reproducible.
Expected behavior
Unstabilized Aender terrain may intentionally change after the last player leaves the dimension, but all chunks belonging to the new reality should be generated coherently without hard chunk-border cuts or missing terrain columns.
Attempted reproduction
The original occurrence happened during this kind of travel. Repeating the steps afterward did not reproduce it.
Potential cause (unconfirmed)
There may be a race between asynchronous portal destination generation and the dimension-empty reality reset:
AenderPortalWarmupadds a portal ticket that loads/generates destination chunks asynchronously.AenderWorldTickEvents.resetVolatileTerrain()callsAenderVolatility.clearForgottenWorld()as soon as the last player leaves.clearForgottenWorld()replaces the global reality salt/epoch and clears cached generation signatures.AenderIslandSampler.islandsForChunk()pass obtains individual region seeds through repeatedAenderVolatility.islandSeed()calls rather than using an immutable per-generation reality snapshot.AenderChunkGenerator.generateChunk()then callsmarkGenerated()using the current epoch, potentially marking a mixed chunk as current and preventing later stale-chunk repair.This theory has not been demonstrated with logging or a deterministic test. A client chunk-packet/render desynchronization remains another possibility; it was not confirmed whether
F3+Awould have repaired the visual or whether collision matched the gaps.Relevant code
AenderPortalWarmup.tickAenderWorldTickEvents.resetVolatileTerrainAenderVolatility.clearForgottenWorldAenderIslandSampler.islandsForChunkAenderChunkGenerator.generateChunkAenderRealityTickEvents.prepareArrivalViewSuggested investigation
F3+A, collision, and server-side block state to distinguish render desync from mixed server terrain.Status
Potential bug / needs reproduction.