terrain.dat binary format¶

Byte-level layout of a Stationeers terrain.dat base-terrain file. One file per base-terrain octree (world-size dependent, see reference table below). The file stores an INT32 LE MaxDepth header followed by a DFS pre-order walk of the octree and then per-vein delta data. The file is NOT internally compressed; the outer save ZIP provides compression.

File layout¶

Bytes 0-3:    INT32 LE  MaxDepth
Bytes 4..N:   DFS pre-order octree nodes (variable length)
Bytes N+1..:  Vein/minable delta data

The file is NOT compressed internally. The outer ZIP provides compression.

Node serialization¶

Every node is one of two forms:

Leaf (3 bytes):

BYTE  flags      bit 0 set (IS_LEAF=0x01), bit 1 optionally set (IS_MODIFIED=0x02)
BYTE  density    0-255 (0 = air, 255 = fully solid)
BYTE  nodeType   VoxelNodeType flags: None=0, Crust=1, Dirt=2, Macro=4, Bedrock=8

Branch (1 byte header, then 8 recursive children):

BYTE  flags      bit 0 clear (not a leaf), bit 1 optionally set (IS_MODIFIED=0x02)
[child 0]        (X low,  Y low,  Z low)
[child 1]        (X high, Y low,  Z low)
[child 2]        (X low,  Y high, Z low)
[child 3]        (X high, Y high, Z low)
[child 4]        (X low,  Y low,  Z high)
[child 5]        (X high, Y low,  Z high)
[child 6]        (X low,  Y high, Z high)
[child 7]        (X high, Y high, Z high)

Child index bit encoding: bit 0 = X >= halfSize, bit 1 = Y >= halfSize, bit 2 = Z >= halfSize.

At depth D, each node covers 2^(MaxDepth - D) voxels per axis. The root (depth 0) covers the whole world. Depth=MaxDepth nodes are single voxels.

Vein data (after octree nodes)¶

INT32  veinCount
For each vein (veinCount times):
  INT16  VeinWorldPosition.x
  INT16  VeinWorldPosition.y
  INT16  VeinWorldPosition.z
  INT16  ClusterPosition.x
  INT16  ClusterPosition.y
  INT16  ClusterPosition.z
  INT32  Data.IdHash       (identifies the vein generation parameters)
  BYTE   minablesLength
  For each minable (minablesLength times):
    BYTE  X
    BYTE  Y
    BYTE  Z
    BYTE  ParentIndex
    BYTE  IsActive         (0x00 or 0x01)

World size reference¶

Short reference copy. Full treatment on ../GameSystems/TerrainOctree.md.

MaxDepth	World size	Base terrain files
10	1024^3	1 (Terrain0.dat)
11	2048^3	8
12	4096^3	64

The Lunar world uses MaxDepth=12 (4096^3).

Verification history¶

2026-04-20: page created from the Research migration. Sources: F0232 (top-level layout), F0233 (node serialization), F0234 (vein data), F0230 (MaxDepth / world size table; primary lives on ../GameSystems/TerrainOctree.md with a short reference copy here per MigrationMap).

Open questions¶

None at creation.