Text Font Map

Text Font Map is a file format used in Sonic the Hedgehog (2006) for storing font character information.

These files are located in text.arc under the ./text/ directory from platform root as *.ftm files.

Specification

Text Font Map uses a Binary Resource container.

Header

The header consists of the following data structure:

Length: 0x14

Offset	Type	Name	Description
0x00	Char[4]	Signature	Always "FNTM".
0x04	UInt32	CodePageCount	The number of code pages mapped in this font. This is a zero-based count, so 0 = 1.
0x08	UInt32	CodePageTableOffset	The offset of the table of code page offsets.
0x0C	Byte	Columns	The number of columns in the font atlas. This field is not used by the game. See Static Font Data.
0x0D	Byte	Rows	The number of rows in the font atlas. This field is not used by the game. See Static Font Data.
0x0E	UInt16	N/A	Unknown. Always 1.
0x10	UInt32	FontNameOffset	The offset of the name of this font.

Code Page Table

The code page table is an indirection table with a fixed size of 256 elements.

Each element is a 32-bit offset that points to a fixed 256 element page of characters in Unicode. These characters consist of cell information and flags that map to the font atlas texture.

Character

Each character is stored as the following data structure:

Length: 0x04

Offset	Type	Name	Description
0x00	Byte	Column	The column of this character cell in the font atlas texture.
0x01	Byte	Row	The row of this character cell in the font atlas texture.
0x02	UInt16	Flags	The flags for this character. If 0xFFFF, this character will be unset.

To get the Unicode character this element pertains to, use the following expression:

Character = (CodePageIndex << 8) | CharacterIndex

Static Font Data

The game stores the last remaining font information in a static array in the executable.

The array can be found at the following addresses:

Platform	File	Virtual Address	Physical Address
Xbox 360	default.xex	0x82B7F860	0xB82860
PlayStation 3	EBOOT.BIN	0x100DDA20	0x178DA20

The array consists of three elements of the following data structure:

Length: 0x1C

Offset	Type	Name	Description
0x00	uint32_t	ID	The ID of this font.
0x04	const char*	pTexturePath	A pointer to the path to the font atlas texture.
0x08	uint16_t	TextureWidth	The width of the font atlas texture.
0x0A	uint16_t	TextureHeight	The height of the font atlas texture.
0x0C	const char*	pTextFontMapPath	A pointer to the path to the Text Font Map for this font.
0x10	const char*	pTextFontProportionPath	A pointer to the path to the Text Font Proportion for this font.
0x14	const char*	pTextFontPicturePath	A pointer to the path to the Text Font Picture for this font. If non-applicable, this should be null.
0x18	uint16_t	CellWidth	The width of each character cell in the font atlas texture.
0x1A	uint16_t	CellHeight	The height of each character cell in the font atlas texture.