TerrainChunkChecksums¶

Stationeers stores one rolling XOR-multiply checksum per base-terrain octree in world.xml. On load, each stored value is compared to the corresponding ReadonlyVoxelOctree.CheckSum. Any mismatch triggers an offer to regenerate ALL terrain (all-or-nothing, no per-chunk reset).

Format and algorithm¶

64 <int> values inside <TerrainChunkChecksums>, one per base-terrain octree. On load, the game compares each against the corresponding ReadonlyVoxelOctree.CheckSum. If ANY mismatch, it offers to regenerate ALL terrain. This is all-or-nothing; you cannot reset one chunk.

The checksum algorithm is a rolling XOR-multiply with prime 257:

checksum = 0
for each node in DFS pre-order:
    checksum = (checksum ^ flags) * 257
    if leaf: checksum = (checksum ^ density) * 257; checksum = (checksum ^ nodeType) * 257
    if branch: for i in 0..7: checksum = (checksum ^ i) * 257; recurse child i

When rewriting terrain.dat, zero all checksums so the game detects a mismatch and rebuilds its base-terrain state cleanly on load.

Verification history¶

2026-04-20: page created from the Research migration. Source: F0235 (TerrainChunkChecksums rolling XOR algorithm).

Open questions¶

None at creation.