Enum CompressionFormat 

pub enum CompressionFormat {
    None,
    Lzma1,
    Lz4,
    Zstd,
    Lz4Block,
}

Compression formats supported by TW Games.

Not all games support all formats. Check their game info to know what formats each game support.

Variants

None

Dummy variant to disable compression.

Lzma1

Legacy format. Supported by all PFH5 games (all Post-WH2 games).

Specifically, Total War games use the Non-Streamed LZMA1 format with the following custom header:

Bytes	Type	Data
4	u32	Uncompressed size (as u32, max at 4GB).
1	u8	LZMA model properties (lc, lp, pb) in encoded form… I think. Usually it’s 0x5D.
4	u32	Dictionary size (as u32)… I think. It’s usually [0x00, 0x00, 0x40, 0x00].

For reference, a normal Non-Streamed LZMA1 header (from the original spec) contains:

Bytes	Type	Data
1	u8	LZMA model properties (lc, lp, pb) in encoded form.
4	u32	Dictionary size (32-bit unsigned integer, little-endian).
8	u64	Uncompressed size (64-bit unsigned integer, little-endian).

This means one has to move the uncompressed size to the correct place in order for a compressed file to be readable, and one has to remove the uncompressed size and prepend it to the file in order for the game to read the compressed file.

Lz4

New format introduced in WH3 6.2.

This is a standard Lz4 implementation, with the following tweaks:

Bytes	Type	Data
4	u32	Uncompressed size (as u32, max at 4GB).
*	&[u8]	Lz4 data, starting with the Lz4 Magic Number.

Zstd

New format introduced in WH3 6.2.

This is a standard Zstd implementation, with the following tweaks:

Bytes	Type	Data
4	u32	Uncompressed size (as u32, max at 4GB).
*	&[u8]	Zstd data, starting with the Zstd Magic Number.

By default the Zstd compression is done with the checksum and content size flags enabled.

Lz4Block

Format used by Shogun 2 Complete Edition PFH3 Packs.

This is a raw Lz4 block, without frame, magic number nor size header. The uncompressed size is stored in the Pack’s index instead, which means this format cannot be auto-detected. Use Decompressible::decompress_lz4_block to decompress it.

Trait Implementations

impl Clone for CompressionFormat

fn clone(&self) -> CompressionFormat

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for CompressionFormat

impl Debug for CompressionFormat

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CompressionFormat

fn default() -> CompressionFormat

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for CompressionFormat

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for CompressionFormat

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&str> for CompressionFormat

fn from(value: &str) -> Self

Converts to this type from the input type.

impl PartialEq for CompressionFormat

fn eq(&self, other: &CompressionFormat) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for CompressionFormat

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for CompressionFormat