Xenos texture info, memory layout and format conversion. More...

#include <memory>
#include <algorithm>
#include <cstring>
#include <functional>
#include <rex/platform.h>
#include <rex/assert.h>
#include <rex/types.h>
#include <rex/xenos/fetch.h>
#include <rex/xenos/format.h>
#include <rex/bit.h>

Classes
struct	rex::xenos::GuestTextureLayout
struct	rex::xenos::GuestTextureLayout::Level
struct	rex::xenos::FormatInfo
struct	rex::xenos::TextureExtent
struct	rex::xenos::TextureMemoryRanges
struct	rex::xenos::TextureInfo
struct	rex::xenos::UntileRegion

Namespaces
namespace	rex

Typedefs
using	rex::xenos::CopyBlockCallback = std::function<void(xenos::Endian, void, const void, size_t)>
using	rex::xenos::UntileCopyBlockCallback = std::function<void(void, const void, size_t)>

Enumerations
enum class	rex::xenos::FormatType : u8 { kResolvable , kUncompressed , kCompressed }

Functions
void	rex::xenos::GetSubresourcesFromFetchConstant (const xenos::TextureFetch &fetch, u32 width_minus_1_out, u32 height_minus_1_out, u32 depth_or_array_size_minus_1_out, u32 base_page_out, u32 mip_page_out, u32 mip_min_level_out, u32 *mip_max_level_out)
u32	rex::xenos::GetPackedMipLevel (u32 width, u32 height)
bool	rex::xenos::GetPackedMipOffset (u32 width, u32 height, u32 depth, xenos::TextureFormat format, u32 mip, u32 &x_blocks, u32 &y_blocks, u32 &z_blocks)
GuestTextureLayout	rex::xenos::GetGuestTextureLayout (xenos::DataDimension dimension, u32 base_pitch_texels_div_32, u32 width_texels, u32 height_texels, u32 depth_or_array_size, bool is_tiled, xenos::TextureFormat format, bool has_packed_levels, bool has_base, u32 max_level)
i32	rex::xenos::GetTiledOffset2D (i32 x, i32 y, u32 pitch, u32 bytes_per_block_log2)
i32	rex::xenos::GetTiledOffset3D (i32 x, i32 y, i32 z, u32 pitch, u32 height, u32 bytes_per_block_log2)
u32	rex::xenos::GetTiledAddressLowerBound2D (u32 left, u32 top, u32 pitch, u32 bytes_per_block_log2)
u32	rex::xenos::GetTiledAddressLowerBound3D (u32 left, u32 top, u32 front, u32 pitch, u32 height, u32 bytes_per_block_log2)
u32	rex::xenos::GetTiledAddressUpperBound2D (u32 right, u32 bottom, u32 pitch, u32 bytes_per_block_log2)
u32	rex::xenos::GetTiledAddressUpperBound3D (u32 right, u32 bottom, u32 back, u32 pitch, u32 height, u32 bytes_per_block_log2)
u8	rex::xenos::SwizzleSigns (const xenos::TextureFetch &fetch)
constexpr bool	rex::xenos::HasNonSignedComponent (u8 packed_signs)
constexpr bool	rex::xenos::HasSignedComponent (u8 packed_signs)
void	rex::xenos::GetClampModesForDimension (const xenos::TextureFetch &fetch, xenos::ClampMode &clamp_x_out, xenos::ClampMode &clamp_y_out, xenos::ClampMode &clamp_z_out)
xenos::TextureFormat	rex::xenos::GetBaseFormat (xenos::TextureFormat texture_format)
size_t	rex::xenos::GetTexelSize (xenos::TextureFormat format)
xenos::TextureFormat	rex::xenos::ColorFormatToTextureFormat (xenos::ColorFormat color_format)
xenos::TextureFormat	rex::xenos::DepthRenderTargetToTextureFormat (xenos::DepthRenderTargetFormat depth_format)
void	rex::xenos::CopySwapBlock (xenos::Endian endian, void output, const void input, size_t length)
void	rex::xenos::ConvertTexelCTX1ToR8G8 (xenos::Endian endian, void output, const void input, size_t output_pitch)
void	rex::xenos::ConvertTexelDXT3AToDXT3 (xenos::Endian endian, void output, const void input, size_t length)
void	rex::xenos::Untile (u8 output_buffer, const u8 input_buffer, const UntileRegion *untile_info)

Detailed Description

Xenos texture info, memory layout and format conversion.

Copyright: Copyright (c) 2026 Tom Clay tomc@.nosp@m.tcte.nosp@m.chstu.nosp@m.ff.c.nosp@m.om All rights reserved.

License: BSD 3-Clause License See LICENSE file in the project root for full license text.

Remarks: Derived from Xenia's xenia/gpu/texture_info.h (Ben Vanik, 2014).; Derived from Xenia's xenia/gpu/texture_util.h (Ben Vanik, 2022).; Derived from Xenia's xenia/gpu/texture_conversion.h (Ben Vanik, 2014).

Typedef Documentation

◆ CopyBlockCallback

using rex::xenos::CopyBlockCallback = std::function<void(xenos::Endian, void*, const void*, size_t)>

Copies a block, swapping bytes by the given endian mode.

Enumeration Type Documentation

◆ FormatType

enum class rex::xenos::FormatType : u8

strong

Enumerator
kResolvable	Uncompressed and usable as a resolve target.
kUncompressed	Uncompressed, not a resolve or memory export target.

Function Documentation

◆ ColorFormatToTextureFormat()

xenos::TextureFormat rex::xenos::ColorFormatToTextureFormat ( xenos::ColorFormat color_format )

inline

Returns the texture format with the same numeric value as a color format.

◆ ConvertTexelCTX1ToR8G8()

void rex::xenos::ConvertTexelCTX1ToR8G8	(	xenos::Endian	endian,
		void *	output,
		const void *	input,
		size_t	output_pitch )

Decodes an 8 byte CTX1 block into 4x4 R8G8 texels.

Parameters

endian	The swap mode of the source block.
output	Destination for 4 rows of 4 R8G8 texels.
input	Source CTX1 block.
output_pitch	Destination row pitch in bytes.

◆ ConvertTexelDXT3AToDXT3()

void rex::xenos::ConvertTexelDXT3AToDXT3	(	xenos::Endian	endian,
		void *	output,
		const void *	input,
		size_t	length )

Expands a DXT3A block into a DXT3 block with the color half zeroed.

Parameters

endian	The swap mode of the source block.
output	Destination 16 byte DXT3 block.
input	Source 8 byte DXT3A block.
length	Unused.

◆ CopySwapBlock()

void rex::xenos::CopySwapBlock	(	xenos::Endian	endian,
		void *	output,
		const void *	input,
		size_t	length )

Copies bytes, swapping them as endian specifies.

◆ DepthRenderTargetToTextureFormat()

xenos::TextureFormat rex::xenos::DepthRenderTargetToTextureFormat ( xenos::DepthRenderTargetFormat depth_format )

inline

Returns the texture format that matches a depth render target format, or TextureFormat(~0) for an unhandled format.

◆ GetBaseFormat()

xenos::TextureFormat rex::xenos::GetBaseFormat ( xenos::TextureFormat texture_format )

inline

Maps a resampling or gamma control variant to its base format.

Returns: The base format, or texture_format when it has no base variant.

◆ GetClampModesForDimension()

void rex::xenos::GetClampModesForDimension	(	const xenos::TextureFetch &	fetch,
		xenos::ClampMode &	clamp_x_out,
		xenos::ClampMode &	clamp_y_out,
		xenos::ClampMode &	clamp_z_out )

Reads the clamp modes a fetch constant uses for its dimension. Unused axes and cube textures get kClampToEdge.

Parameters

clamp_x_out	Receives the X clamp mode.
clamp_y_out	Receives the Y clamp mode.
clamp_z_out	Receives the Z clamp mode.

◆ GetGuestTextureLayout()

GuestTextureLayout rex::xenos::GetGuestTextureLayout	(	xenos::DataDimension	dimension,
		u32	base_pitch_texels_div_32,
		u32	width_texels,
		u32	height_texels,
		u32	depth_or_array_size,
		bool	is_tiled,
		xenos::TextureFormat	format,
		bool	has_packed_levels,
		bool	has_base,
		u32	max_level )

Calculates the guest memory layout of a texture, all zero when it has no texels.

Parameters

base_pitch_texels_div_32	Base level row pitch in texels divided by 32.
depth_or_array_size	Depth for 3D textures, array size otherwise.
is_tiled	True for tiled data, false for linear.
has_packed_levels	True when small levels share a packed mip tail.
has_base	True when the base level is present.

◆ GetPackedMipLevel()

u32 rex::xenos::GetPackedMipLevel	(	u32	width,
		u32	height )

inline

Returns the first mip level stored in the packed mip tail.

◆ GetPackedMipOffset()

bool rex::xenos::GetPackedMipOffset	(	u32	width,
		u32	height,
		u32	depth,
		xenos::TextureFormat	format,
		u32	mip,
		u32 &	x_blocks,
		u32 &	y_blocks,
		u32 &	z_blocks )

Finds the offset of a mip level within the packed mip tail.

Parameters

depth	Depth in texels, 1 for textures other than 3D.
x_blocks	Receives the X offset in blocks.
y_blocks	Receives the Y offset in blocks.
z_blocks	Receives the Z offset in blocks.

Returns: False when the level is not packed, with all offsets set to 0.

◆ GetSubresourcesFromFetchConstant()

void rex::xenos::GetSubresourcesFromFetchConstant	(	const xenos::TextureFetch &	fetch,
		u32 *	width_minus_1_out,
		u32 *	height_minus_1_out,
		u32 *	depth_or_array_size_minus_1_out,
		u32 *	base_page_out,
		u32 *	mip_page_out,
		u32 *	mip_min_level_out,
		u32 *	mip_max_level_out )

Reads the size and present levels from a fetch constant. Every output pointer may be null.

Parameters

width_minus_1_out	Receives the width in texels minus 1.
height_minus_1_out	Receives the height in texels minus 1.
depth_or_array_size_minus_1_out	Receives the depth or array size minus 1, 5 for cubes.
base_page_out	Receives the base level page, 0 when the base level is absent.
mip_page_out	Receives the mip page, 0 when no mips are present.
mip_min_level_out	Receives the first present level.
mip_max_level_out	Receives the last present level.

◆ GetTexelSize()

size_t rex::xenos::GetTexelSize ( xenos::TextureFormat format )

inline

Returns the size of one texel of an uncompressed format in bytes, or 0 for an unhandled format.

◆ GetTiledAddressLowerBound2D()

u32 rex::xenos::GetTiledAddressLowerBound2D	(	u32	left,
		u32	top,
		u32	pitch,
		u32	bytes_per_block_log2 )

inline

Returns the lowest address a 2D region can touch, the origin of its first 32x32 tile. The offset is in bytes.

Parameters

left	Left edge in blocks.
top	Top edge in blocks.
pitch	Row pitch in blocks.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ GetTiledAddressLowerBound3D()

u32 rex::xenos::GetTiledAddressLowerBound3D	(	u32	left,
		u32	top,
		u32	front,
		u32	pitch,
		u32	height,
		u32	bytes_per_block_log2 )

inline

Returns the lowest address a 3D region can touch, the origin of its first 32x32x4 tile. The offset is in bytes.

Parameters

left	Left edge in blocks.
top	Top edge in blocks.
pitch	Row pitch in blocks.
height	Height in blocks.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ GetTiledAddressUpperBound2D()

u32 rex::xenos::GetTiledAddressUpperBound2D	(	u32	right,
		u32	bottom,
		u32	pitch,
		u32	bytes_per_block_log2 )

Returns the exclusive upper address bound of a 2D region, or 0 for an empty region. The region may extend past the pitch.

Parameters

right	Exclusive right edge in blocks.
bottom	Exclusive bottom edge in blocks.
pitch	Row pitch in blocks.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ GetTiledAddressUpperBound3D()

u32 rex::xenos::GetTiledAddressUpperBound3D	(	u32	right,
		u32	bottom,
		u32	back,
		u32	pitch,
		u32	height,
		u32	bytes_per_block_log2 )

Returns the exclusive upper address bound of a 3D region, or 0 for an empty region. The region may extend past the pitch and height.

Parameters

right	Exclusive right edge in blocks.
bottom	Exclusive bottom edge in blocks.
back	Exclusive back layer.
pitch	Row pitch in blocks.
height	Height in blocks.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ GetTiledOffset2D()

i32 rex::xenos::GetTiledOffset2D	(	i32	x,
		i32	y,
		u32	pitch,
		u32	bytes_per_block_log2 )

Returns the offset of a block in a 2D tiled texture. Negative coordinates are valid.

Parameters

pitch	Row pitch in blocks, aligned to 32 internally.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ GetTiledOffset3D()

i32 rex::xenos::GetTiledOffset3D	(	i32	x,
		i32	y,
		i32	z,
		u32	pitch,
		u32	height,
		u32	bytes_per_block_log2 )

Returns the offset of a block in a 3D tiled texture. Each 32 block row by 4 layer portion occupies its own 4 KB aligned range.

Parameters

pitch	Row pitch in blocks, aligned to 32 internally.
height	Height in blocks, aligned to 32 internally.
bytes_per_block_log2	log2_floor of the bytes per block.

◆ HasNonSignedComponent()

bool rex::xenos::HasNonSignedComponent ( u8 packed_signs )

constexpr

Reports whether any component is not kSigned.

Parameters

packed_signs Packed signs from SwizzleSigns.

◆ HasSignedComponent()

bool rex::xenos::HasSignedComponent ( u8 packed_signs )

constexpr

Reports whether any component is kSigned.

Parameters

packed_signs Packed signs from SwizzleSigns.

◆ SwizzleSigns()

u8 rex::xenos::SwizzleSigns ( const xenos::TextureFetch & fetch )

Packs the TextureSign of each component after the swizzle. Constant 0 and 1 count as unsigned unless every other component is signed.

Returns: Four TextureSign values, 2 bits each.

◆ Untile()

void rex::xenos::Untile	(	u8 *	output_buffer,
		const u8 *	input_buffer,
		const UntileRegion *	untile_info )

Converts a region of a 2D tiled texture to linear layout.

Parameters

output_buffer	Linear destination.
input_buffer	Tiled source.
untile_info	The region, pitches, formats and block copy callback.

Classes

Namespaces

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ CopyBlockCallback

Enumeration Type Documentation

◆ FormatType

Function Documentation

◆ ColorFormatToTextureFormat()

◆ ConvertTexelCTX1ToR8G8()

◆ ConvertTexelDXT3AToDXT3()

◆ CopySwapBlock()

◆ DepthRenderTargetToTextureFormat()

◆ GetBaseFormat()

◆ GetClampModesForDimension()

◆ GetGuestTextureLayout()

◆ GetPackedMipLevel()

◆ GetPackedMipOffset()

◆ GetSubresourcesFromFetchConstant()

◆ GetTexelSize()

◆ GetTiledAddressLowerBound2D()

◆ GetTiledAddressLowerBound3D()

◆ GetTiledAddressUpperBound2D()

◆ GetTiledAddressUpperBound3D()

◆ GetTiledOffset2D()

◆ GetTiledOffset3D()

◆ HasNonSignedComponent()

◆ HasSignedComponent()

◆ SwizzleSigns()

◆ Untile()