SimGrid

From SC4D Encyclopaedia
Jump to navigation Jump to search

SimGrids are files that can be found within Savegame files. They come in 6 different types:

Type ID Name
0x49b9e602 SimGridUint8
0x49b9e603 SimGridSint8
0x49b9e604 SimGridUint16
0x49b9e605 SimGridSint16
0x49b9e606 SimGridUint32
0x49b9e60a SimGridFloat32

They are basically rectangular grids that hold values that the game needs for the simulation. Most of them can be viewed in the Mayor Mode Data Views.

This particular subfile was decoded by smf_16.

Structure

DWORD	Subfile Size in bytes
DWORD	CRC
DWORD	Memory address
WORD	Major version (0x0001)
BYTE	Unknown
DWORD	Type ID (0x49b9e602 to 0x49b9e60a)
DWORD	Data ID
DWORD	Resolution
DWORD	Resolution power
DWORD	X size
DWORD	Z size
DWORD	Unknown
DWORD	Unknown
DWORD	Unknown
DWORD	Unknown
	TYPE	Values (repeat for x*z times, byte size depends on Type ID)

Data ID

The Data ID specifies what kind of data this SimGrid holds. Not all Data IDs are know yet.

Data ID Data type Name Description
0x41800000 Sint8 City Overview The values in it correspond ZoneTypes from the Lot Subfile
0x69d5c40e Float32 Traffic related, probably all traffic
0x69d5c3ac Float32 Traffic related, probably car traffic
0x49d5bc40 Int16 Air pollution

Resolution and resolution power

The SimGrids don't always hold values per tile. If the values are set per 1x1, resolution is 1, if values are set per 2x2, resolution is 2 etc. This value is always a power of 2 (so 1x1, 2x2, 4x4, ...) The exponent is given by the resolution power.

X size & Z size

The amount of rows and columns in the grid. For a small 64x64 city and resolution 1, X & Z size are 64. When the resolution is 2, X & Z size are 32 and so on.

Values

The values for each cell of the grid. The byte size of each value depends on the type of the SimGrid. For Uint8's, this is 1 byte, for Float32's this is 4 bytes and so on.

The order of values is column first. So first comes (0,0), then (0,1), then (0, 2) and so on.