TXTR (Tropical Freeze)

See TXTR (File Format) for the other revisions of this format.

The TXTR format is Tropical Freeze's texture format. The image data in the GPU buffer is compressed using LZSS compression.

This file format needs more research There are a couple unknowns in the header. It would also be good to have some documentation on how to deswizzle/decompress different texture formats.

Format

The format starts with the typical form descriptor found in every Tropical Freeze format. Following that, there's a HEAD header section that contains most of the texture parameters, then the GPU section containing the actual compressed image data. This is the structure of the HEAD section:

Offset	Type	Count	Name	Notes
0x0	Chunk Descriptor	1	HEAD Chunk Descriptor
0x18	u32	1	Texture Type	Describes the type/dimensionality of the texture (2D texture, 3D texture, cubemap, array of 2D images, etc).
0x1C	u32	1	Texture Format	Describes the format that the image data is encoded in.
0x20	u32	1	Width	Texture X resolution.
0x24	u32	1	Height	Texture Y resolution.
0x28	u32	1	Depth	Texture Z resolution.
0x2C	u32	1	Tile Mode	Indicates how the texture image data is tiled.
0x30	u32	1	Swizzle	Indicates how the texture image data is swizzled.
0x34	u32	1	Mipmap Count
0x38	u32	Mipmap Count	Mipmap Sizes	The size of the base level mipmap is calculated with padding and alignment taken into account. The size of subsequent mipmaps is calculated as Width*Height*Depth*BPP/8. This does not take padding and alignment into account, and so it does not accurately reflect the amount of space the mipmap takes up in the file, and it cannot be used to accurately locate and read mipmap data. The offset and size needs to be calculated from the other parameters in the header. The game calculates this data by calling GX2CalcSurfaceSizeAndAlignment.
	u32	1	Unknown	This parameter is part of NTextureFormat::STextureSamplerData (along with the next 4 parameters)
	u8	1	Texture Filter	Determines how the texture is filtered when sampled.
	u8	1	Texture Wrap X	Determines how the texture wraps on the X coordinate.
	u8	1	Texture Wrap Y	Determines how the texture wraps on the Y coordinate.
	u8	1	Texture Wrap Z	Determines how the texture wraps on the Z coordinate.

Texture Type

This enum basically maps directly to a GX2SurfaceDim enum.

ID	Type
0	1D Texture
1	2D Texture
2	3D Texture
3	Cube Texture
4	1D Texture Array
5	2D Texture Array
6	Multisampled 2D Texture
7	Multisampled 2D Texture Array

Texture Format

ID	GX2SurfaceFormat
0x00	GX2_SURFACE_FORMAT_TC_R8_UNORM
0x01	GX2_SURFACE_FORMAT_TC_R8_SNORM
0x02	GX2_SURFACE_FORMAT_TC_R8_UINT
0x03	GX2_SURFACE_FORMAT_TC_R8_SINT
0x04	GX2_SURFACE_FORMAT_TCD_R16_UNORM
0x05	GX2_SURFACE_FORMAT_TC_R16_SNORM
0x06	GX2_SURFACE_FORMAT_TC_R16_UINT
0x07	GX2_SURFACE_FORMAT_TC_R16_SINT
0x08	GX2_SURFACE_FORMAT_TC_R16_FLOAT
0x09	GX2_SURFACE_FORMAT_TC_R32_UINT
0x0A	GX2_SURFACE_FORMAT_TC_R32_SINT
0x0B	GX2_SURFACE_FORMAT_INVALID
0x0C	GX2_SURFACE_FORMAT_TCS_R8_G8_B8_A8_UNORM
0x0D	GX2_SURFACE_FORMAT_TCS_R8_G8_B8_A8_SRGB
0x0E	GX2_SURFACE_FORMAT_TC_R16_G16_B16_A16_FLOAT
0x0F	GX2_SURFACE_FORMAT_TC_R32_G32_B32_A32_FLOAT
0x10	GX2_SURFACE_FORMAT_TCD_R16_UNORM
0x11	GX2_SURFACE_FORMAT_TCD_R16_UNORM
0x12	GX2_SURFACE_FORMAT_D_D24_S8_UNORM
0x13	GX2_SURFACE_FORMAT_TCD_R32_FLOAT
0x14	GX2_SURFACE_FORMAT_T_BC1_UNORM
0x15	GX2_SURFACE_FORMAT_T_BC1_SRGB
0x16	GX2_SURFACE_FORMAT_T_BC2_UNORM
0x17	GX2_SURFACE_FORMAT_T_BC2_SRGB
0x18	GX2_SURFACE_FORMAT_T_BC3_UNORM
0x19	GX2_SURFACE_FORMAT_T_BC3_SRGB
0x1A	GX2_SURFACE_FORMAT_T_BC4_UNORM
0x1B	GX2_SURFACE_FORMAT_T_BC4_SNORM
0x1C	GX2_SURFACE_FORMAT_T_BC5_UNORM
0x1D	GX2_SURFACE_FORMAT_T_BC5_SNORM
0x1E	GX2_SURFACE_FORMAT_TC_R11_G11_B10_FLOAT
0x1F	GX2_SURFACE_FORMAT_TCD_R32_FLOAT
0x20	GX2_SURFACE_FORMAT_TC_R16_G16_FLOAT
0x21	GX2_SURFACE_FORMAT_TC_R8_G8_UNORM

Texture Filter

Invalid values default to 1 (linear).

ID	GX2TexMipFilterType
0	GX2_TEX_MIP_FILTER_POINT
1	GX2_TEX_MIP_FILTER_LINEAR

Texture Wrap

Invalid values default to 0 (clamp).

ID	GX2TexClamp
0	GX2_TEX_CLAMP_CLAMP
1	GX2_TEX_CLAMP_WRAP
2	GX2_TEX_CLAMP_MIRROR
3	GX2_TEX_CLAMP_MIRROR_ONCE

PAK Metadata

The pak metadata for the TXTR format primarily contains compression-related information and provides the values required to decompress it.

Offset	Type	Count	Name	Notes
0x0	u32	1	Unknown	Always 4
0x4	u32	1	Unknown
0x8	u32	1	GPU Section Offset	Relative to the start of the file
0xC	u32	1	Base Alignment	Alignment of the surface image data
0x10	u32	1	GPU Data Start	This is the offset to the start of the GPU data, immediately after the GPU section header.
0x14	u32	1	GPU Section Size	Matches the size from the GPU section header.
0x18	u32	1	Compressed Buffer Count
0x1C	Compressed Buffer	Compressed Buffer Count	Compressed Buffer Array

Compressed Buffer

This is a small struct that defines a compressed data buffer within the GPU section.

Offset	Type	Name	Notes
0x0	u32	Decompressed Size
0x4	u32	Compressed Size
0x8	u32	Offset	Relative to after the GPU section header