EFTB

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EFTB files define certain graphical effects of objects such as emissions, particles, and shaders.


EFTB File Layout

EFTB files are made up of a header and four arrays that are aligned to 16 bytes.

  • Emitter Set Array
  • Texture Array
  • PRM[check] Array
  • Shader Array

Each array serves as a root node in a tree structure.

EFTB Header

EFTB's header is 48 bytes and is not yet well-understood.

Header Structure

Offset (h) Size Data Type Description
0x00 4 String file signature (magic) (45 46 54 42 or "EFTB")
0x04 4 Unsigned Int Unknown (00 00 00 14)
0x08 4 String Unknown (47 61 6d 65 or "Game")
...

Nodes

Each node in an array's tree structure is made up of a header and three optional sections.

  • Binary data
  • Attribute nodes[check]
  • Child nodes

Node Header Structure

Node headers typically have the same 32-byte structure, though some are longer and some calculate certain values differently.

Offset (h) Size Data Type Description
0x00 4 Unsigned Int Signature (magic)
0x04 4 Unsigned Int Node size. Different node types calculate this differently.
0x08 4 Unsigned Int Offset to the first child node, or FF FF FF FF if there are no children
0x0c 4 Unsigned Int Offset to the next sibling node, or FF FF FF FF if there are no more siblings
0x10 4 Unsigned Int Offset to the first attribute[check], or FF FF FF FF if there are no attributes
0x14 4 Unsigned Int Offset to the binary data, or the size of the header
0x18 4 Padding
0x1c 2 Unsigned Short Number of child nodes. Shaders' use of this value is unknown.
0x1e 2 Unsigned Short Unknown (00 01)

Emitter Sets (ESTA)

The Emitter Set Array (ESTA) contains any number of Emitter Sets (ESET) as child nodes.

Emitter Set (ESET)

Emitter sets (ESET) contain 0x60 bytes of data:

Offset (h) Size (h) Data Type Description
0x10 0x40 String 0-terminated string representing the name of the emitter set
0x50 0x04 Unsigned Int Total number of emitters in the set, including all descendant nodes
0x5a 0x02 Unsigned Short Unknown
0x5f 0x01 Byte Unknown. Can be 0x00 or 0xff

The rest of the data block is padding.

Emitter sets also contain any number of Emitters (EMTR) as child nodes.

Emitter (EMTR)

Emitters (EMTR) contain the following data:

Offset (h) Size (h) Description
0x00 0x60 Name block, like in ESET
0x60 0x18 Six Unsigned Ints specifying the sizes of the color arrays
  • Color 0
  • Alpha 0
  • Color 1
  • Alpha 1
  • Scale[check]
  • Unknown
... Unknown
0x420 0x80 Color 0 array (eight sets of four 32-bit floats describing Red, Green, Blue, and Time)
0x4a0 0x80 Alpha 0 array
0x520 0x80 Color 1 array
0x5a0 0x80 Alpha 1 array
0x620 0x40 Unknown array
0x660 0x80 Scale[check] array
... Unknown
0xa08 0x10 Constant Color 0 if Color 0 array is empty
0xa18 0x10 Constant Color 1 if Color 1 array is empty
0xa28 0x30 Unknown
0xa58 0x60 Three 0x20 blocks consisting of a 64-bit Unsigned Long Texture ID and 0x18 bytes padding
0xab8 0x30 Unknown

Emitters can also have any number of attribute nodes (e.g. CADP, CSDP, FCSF), the purpose of which is currently unknown, as well as child emitter nodes.

Attributes

CADP causes an emitter to cast light on surrounding surfaces. It contains the following data:

Offset (h) Size Data Type Description
0x00 0x04 Bitmask Flag determining the light's shape
0x04 (variable) Float A variable number of floats whose purpose is unknown

Shape flag:

Flag Description
0x00 Sphere
0x01 Rod (e.g. swords)
0x02 Changes the orientation of Rod
0x04 Adds a dead zone to the center of Rod
0x08 Wide cone
0x10 Square
0x20 Point
0x40 Widens the Point

Textures (TEXA)

The Texture Array (TEXA) contains any number of Textures (TEXR), with each texture containing a single GX2 Texture Block (GX2B). The TEXA tree is flattened such that all TEXR nodes appear first, followed by all of their child GX2B nodes.

(PRMA)

The PRMA[check] contains any number of PRIM[check] nodes.

Shaders (SHDA)

The Shader Array (SHDA) contains a single[check] GX2 Shader Block (SHDB).