Module binary 

This module contains the traits ReadBytes and WriteBytes, used to read binary data into known types and write them back to binary.

These traits are automatically implemented for anything that implements Read + Seek (for ReadBytes) or Write (for WriteBytes).

Examples

To read data using the ReadBytes trait, we can do this:

use std::io::Cursor;

use rpfm_lib::binary::ReadBytes;

let data = vec![10, 0, 87, 97, 104, 97, 104, 97, 104, 97, 104, 97];
let mut cursor = Cursor::new(data);
let string = ReadBytes::read_sized_string_u8(&mut cursor).unwrap();
println!("{}", string);

And for writing data using the WriteBytes trait, we can do this:

use rpfm_lib::binary::WriteBytes;

let mut data = vec![];
data.write_string_u8("Wahahahaha").unwrap();
println!("{:?}", data);

Check each trait docs for more info about all the types that can be read/written.

Simple types

The most simple and common readable/writable types (always using LittleEndian) are:

Type	Bytes	Binary Format	Example	Explanation
bool	1	00 or 01	0/1	Boolean value, 0 is false, 1 is true. Read with ReadBytes::read_bool, write with WriteBytes::write_bool.
u8	1	05	5	Unsigned Integer. Read with ReadBytes::read_u8, write with WriteBytes::write_u8.
u16	2	05 00	5	Unsigned Integer. Read with ReadBytes::read_u16, write with WriteBytes::write_u16.
u24	3	05 00 00	5	Unsigned Integer. Read with ReadBytes::read_u24, write with WriteBytes::write_u24.
u32	4	05 00 00 00	5	Unsigned Integer. Read with ReadBytes::read_u32, write with WriteBytes::write_u32.
u64	8	05 00 00 00 00 00 00 00	5	Unsigned Integer. Read with ReadBytes::read_u64, write with WriteBytes::write_u64.
i8	1	05	5	Signed Integer. Read with ReadBytes::read_i8, write with WriteBytes::write_i8.
i16	2	05 00	5	Signed Integer. Read with ReadBytes::read_i16, write with WriteBytes::write_i16.
i24	3	05 00 00	5	Signed Integer. Read with ReadBytes::read_i24, write with WriteBytes::write_i24.
i32	4	05 00 00 00	5	Signed Integer. Read with ReadBytes::read_i32, write with WriteBytes::write_i32.
i64	8	05 00 00 00 00 00 00 00	5	Signed Integer. Read with ReadBytes::read_i64, write with WriteBytes::write_i64.
f32	4	00 00 80 3F	1.0	Floating Point Value. Read with ReadBytes::read_f32, write with WriteBytes::write_f32.
f64	8	00 00 00 00 00 00 F0 3F	1.0	Floating Point Value. Read with ReadBytes::read_f64, write with WriteBytes::write_f64.
StringU8	2 (Length, u16) + Length.	06 00 48 65 6C 6C 6F 77	Hellow	String encoded in UTF-8, with the first two bytes being the length of the String, in bytes. Read with ReadBytes::read_sized_string_u8, write with WriteBytes::write_sized_string_u8.
StringU16	2 (Length, u16) + Length * 2.	06 00 48 00 65 00 6C 00 6C 00 6F 00 77 00	Hellow	String encoded in UTF-16, with the first two bytes being the length of the String, in characters. Read with ReadBytes::read_sized_string_u16, write with WriteBytes::write_sized_string_u16.

Complex types

Apart of these, there are a few more complex types supported:

Type	Bytes	Binary Format	Example	Explanation
Optional i16	3	01 05 00	5	Signed Integer with a boolean before. If the boolean is false, the value following it is always 0. Read with ReadBytes::read_optional_i16, write with WriteBytes::write_optional_i16.
Optional i32	5	01 05 00 00 00	5	Signed Integer with a boolean before. If the boolean is false, the value following it is always 0. Read with ReadBytes::read_optional_i32, write with WriteBytes::write_optional_i32.
Optional i64	9	01 05 00 00 00 00 00 00 00	5	Signed Integer with a boolean before. If the boolean is false, the value following it is always 0. Read with ReadBytes::read_optional_i64, write with WriteBytes::write_optional_i64.
OptionalStringU8	1 (bool) + 2 (Length, u16) + Length.	01 06 00 48 65 6C 6C 6F 77	Hellow	A StringU8 with a boolean before. If the boolean is false, there’s no string after it. Read with ReadBytes::read_optional_string_u8, write with WriteBytes::write_optional_string_u8.
OptionalStringU16	1 (bool) + 2 (Length, u16) + Length.	01 06 00 48 00 65 00 6C 00 6C 00 6F 00 77 00	Hellow	A StringU16 with a boolean before. If the boolean is false, there’s no string after it. Read with ReadBytes::read_optional_string_u16, write with WriteBytes::write_optional_string_u16.
StringU8 0-Terminated	Variable length, until there’s a 00 byte.	48 65 6C 6C 6F 77 00	Hellow	A StringU8 without a size before it. The string just continues until a 00 byte is found. Read with ReadBytes::read_string_u8_0terminated, write with WriteBytes::write_string_u8_0terminated.
StringU8 0-Padded	Fixed length, depends on the string.	48 65 6C 6C 6F 77 00 00	Hellow (max size 8)	A StringU8 without a size before it. Once the string ends, it continues with 00 until it reaches a specific length (usually X*2). Read with ReadBytes::read_string_u8_0padded, write with WriteBytes::write_string_u8_0padded.
StringU16 0-Padded	Fixed length, depends on the string.	48 00 65 00 6C 00 6C 00 6F 00 77 00 00 00 00 00	Hellow (max size 8)	Same as the StringU8 0-Padded, but each character is 2 bytes. Once the string ends, it continues with 00 00 until it reaches a specific length (usually X*2). Read with ReadBytes::read_string_u16_0padded, write with WriteBytes::write_string_u16_0padded.
RGB	4	33 44 55 00	#554433	RGB Colour, written as Hex Values with the format BBGGRR00. Read with ReadBytes::read_string_colour_rgb, write with WriteBytes::write_string_colour_rgb.

There are some even more complex types used by specific files, like ISO-8859-1 Strings or Number Packs. Those are explained in their respective file’s documentation.

Traits

ReadBytes

This trait allow us to easily read all kind of data from a source that implements Read + Seek.

WriteBytes

This trait allow us to easily write all kind of data types to something that implements Write.