Structures

The majority of this information is from the SCE PS3 SDK: CellGcmTexture datatype reference, though Burnout's debugging symbols were also referenced.

renderengine::Texture

Offset	Length	Type	Name	Description	Comments
0x0	0x1	uint8_t	m_format	Texture format	See format
0x1	0x1	uint8_t	m_mipmap	Number of mipmap levels (1-13)	Sum of the maximum number of mipmap levels for the texture + 1
0x2	0x1	uint8_t	m_dimension	Texture dimension	See dimension
0x3	0x1	uint8_t	m_cubemap	Enable or disable cube mapping	See CubeMapEnable
0x4	0x4	uint32_t	m_remap	Method of selecting each element of the color value	See remap
0x8	0x2	uint16_t	m_width	Width of texture (1-4096)
0xA	0x2	uint16_t	m_height	Height of texture (1-4096)
0xC	0x2	uint16_t	m_depth	Depth of texture (1-512)	Always 1 in Burnout as 3D textures are not used
0xE	0x1	uint8_t	m_location	Location of texture data (main memory or local memory)	See location
0xF	0x1	uint8_t	m_padding	Padding
0x10	0x4	uint32_t	m_pitch	Pitch size of texture	See pitch
0x14	0x4	uint32_t	m_offset	Offset value from the base address of the texture data location
0x18	0x4	void*	m_buffer		Texture
0x1C	0x4	Type	m_storeType	Store type
0x20	0x4	uint32_t	m_storeFlags	Store flags	Seemingly unused

Format

Swizzling and normalization is not used in Burnout, so these flags are unused.

Below is the bitwise structure for the format field.

Offset (bits)	Length (bits)	Description	Comments
0	1		Unused, always 1
1	1	Normalization flag	See normalization flag
2	1	Swizzle flag	See swizzle flag
3	5	Color format	See color format

For example, the following is the DXT5 format as found in Burnout:

Format 0x88
Bit value	1	0	0	0	1	0	0	0
Parsed value	1	0	0	8
Description	Unused	CELL_GCM_TEXTURE_NR	CELL_GCM_TEXTURE_SZ	CELL_GCM_TEXTURE_COMPRESSED_DXT45

Remap

The remap order is only used when one of the following color formats is specified:

CELL_GCM_TEXTURE_COMPRESSED_HILO8
CELL_GCM_TEXTURE_COMPRESSED_HILO_S8
CELL_GCM_TEXTURE_X16
CELL_GCM_TEXTURE_Y16_X16
CELL_GCM_TEXTURE_Y16_X16_FLOAT

These are not used in Burnout, so the remap field is unused.

Below is the bitwise structure for the remap field. It is unclear whether this is in MSB 0 or LSB 0 notation.

Offset (bits)	Length (bits)	Description
0	16	Remap order
16	2	Output blue element
18	2	Output green element
20	2	Output red element
22	2	Output alpha element
24	2	Input blue element
26	2	Input green element
28	2	Input red element
30	2	Input alpha element

Pitch

Pitch is the texture width multiplied by the bytes per texel. It must be specified when using linear texture formats or DXT compression. If the texture is swizzled or the DXT texture width is a power of 2, pitch is ignored. Otherwise, it must be 16 or more.

Burnout only uses textures with widths at powers of 2, so pitch is unused. However, if it becomes necessary to calculate pitch, the following formula may be used for DXT textures:

pitch = floor((width+3)/4)* block_size

Where block_size is 8 for DXT1 and 16 for DXT2 through DXT5.

Enumerations

Much of this information is from the SCE PS3 SDK: GCM Method Macros Overview, section 6.4: TextureFormat. Some information is also from the CellGcmTexture datatype documentation. Various other sources are used.

Color format

Name	Value	Comments
CELL_GCM_TEXTURE_B8	0x81	One 8-bit unsigned integer
CELL_GCM_TEXTURE_A1R5G5B5	0x82	One 1-bit value and three unsigned 5-bit integers
CELL_GCM_TEXTURE_A4R4G4B4	0x83	Four unsigned 4-bit values
CELL_GCM_TEXTURE_R5G6B5	0x84	5-bit, 6-bit, and 5-bit unsigned integers
CELL_GCM_TEXTURE_A8R8G8B8	0x85	Four 8-bit unsigned integers
CELL_GCM_TEXTURE_COMPRESSED_DXT1	0x86	4x4 pixels compressed to 8 bytes
CELL_GCM_TEXTURE_COMPRESSED_DXT23	0x87	4x4 pixels compressed to 16 bytes
CELL_GCM_TEXTURE_COMPRESSED_DXT45	0x88	4x4 pixels compressed to 16 bytes
CELL_GCM_TEXTURE_G8B8	0x8B	Two 8-bit unsigned integers
CELL_GCM_TEXTURE_R6G5B5	0x8F	6-bit, 5-bit, and 5-bit unsigned integers
CELL_GCM_TEXTURE_DEPTH24_D8	0x90	One 24-bit fixed, and 8-bit dummy data
CELL_GCM_TEXTURE_DEPTH24_D8_FLOAT	0x91	One 24-bit float, and 8-bit dummy data
CELL_GCM_TEXTURE_DEPTH16	0x92	One 16-bit fixed
CELL_GCM_TEXTURE_DEPTH16_FLOAT	0x93	One 16-bit float value
CELL_GCM_TEXTURE_X16	0x94	One 16-bit integer
CELL_GCM_TEXTURE_Y16_X16	0x95	Two 16-bit integer
CELL_GCM_TEXTURE_R5G5B5A1	0x97	Three 5-bit unsigned integers, and one 1-bit value
CELL_GCM_TEXTURE_COMPRESSED_HILO8	0x98	Two unsigned 16-bit values compressed to two 8-bit values
CELL_GCM_TEXTURE_COMPRESSED_HILO_S8	0x99	Two signed 16-bit values compressed to two 8-bit values
CELL_GCM_TEXTURE_W16_Z16_Y16_X16_FLOAT	0x9A	Four 16-bit float values
CELL_GCM_TEXTURE_W32_Z32_Y32_X32_FLOAT	0x9B	Four 32-bit float values
CELL_GCM_TEXTURE_X32_FLOAT	0x9C	One 32-bit float value
CELL_GCM_TEXTURE_D1R5G5B5	0x9D	1-bit dummy data, and three 5-bit unsigned integers
CELL_GCM_TEXTURE_D8R8G8B8	0x9E	8-bit dummy data, and three 8-bit unsigned integers
CELL_GCM_TEXTURE_Y16_X16_FLOAT	0x9F	Two 16-bit float values
CELL_GCM_TEXTURE_COMPRESSED_B8R8_G8R8	0xAD	Two pixels compressed in the YUV format to 32 bits
CELL_GCM_TEXTURE_COMPRESSED_R8B8_R8G8	0xAE	Two pixels compressed in the YUV format to 32 bits

Swizzle flag

Swizzle can only be used when the width is not a power of two. Pitch must be specified.

Name	Value	Comments
CELL_GCM_TEXTURE_SZ	0x0	Use the swizzle format
CELL_GCM_TEXTURE_LN	0x20	Use the linear format

Normalization flag

Name	Value	Comments
CELL_GCM_TEXTURE_NR	0x0	Normalize texture coordinates
CELL_GCM_TEXTURE_UN	0x40	Do not normalize texture coordinates

Dimension

Depth textures cannot be 3D.

Name	Value	Comments
CELL_GCM_TEXTURE_DIMENSION_1	1	1D texture
CELL_GCM_TEXTURE_DIMENSION_2	2	2D texture
CELL_GCM_TEXTURE_DIMENSION_3	3	3D texture

CubeMapEnable

Name	Value	Comments
CELL_GCM_FALSE	0	Disable
CELL_GCM_TRUE	1	Enable

Location

Name	Value	Comments
CELL_GCM_LOCATION_LOCAL + 1	1	Local memory
CELL_GCM_LOCATION_MAIN + 1	2	Main memory

renderengine::Texture::Type

Name	Value	Comments
TYPE_NA	-1
TYPE_1D	1
TYPE_2D	2
TYPE_3D	3
TYPE_CUBE	0x10002
TYPE_FORCEENUMSIZEINT	0x7FFFFFFF