SHARCFB File Format

AGL > Binary Shader Archive (SHARCFB)

A SHARCFB file contains compiled shaders. This page describes version 8 of the file format.

File structure
Header
Shader binary section
Shader program section

Header

In little endian mode, the whole header is swapped (even the magic number).

Offset	Size	Description
0x0	4	Magic number: SHAB
0x4	4	Version number
0x8	4	Filesize
0xC	4	Endianness (0=big, 1=little)
0x10	4	Always 0
0x14	4	Length of filename string (including null terminator)
0x18		Filename string (null-terminated)

Shader Binary Section

This section contains the compiled shader binaries.

Offset	Size	Description
0x0	4	Size of shader binary section
0x4	4	Number of shader binaries
0x8		Shader binaries

Shader Binary

Offset	Size	Description
0x0	4	Size (or offset to next shader binary)
0x4	4	Type: 0 = GX2VertexShader 1 = GX2PixelShader 2 = GX2GeometryShader
0x8	4	Offset to shader data
0xC	4	Size of shader data
0x10		Shader data. This uses the same format as the GX2 structures, but pointers are stored as offsets relative to the start of the shader data.

Shader Program Section

This section contains named shader programs that reference shaders from the shader binary section.

Offset	Size	Description
0x0	4	Size of shader program section
0x4	4	Number of shader programs
0x8		Shader programs

Shader Program

Offset	Size	Description
0x0	4	Size (or offset to next shader program)
0x4	4	Length of name string (including null terminator)
0x8	4	A bitfield defining the kind of shaders in this program: 0x1: Vertex shader 0x2: Pixel shader 0x4: Geometry shader A shader program must contain a vertex and a pixel shader and may optionally contain a geometry shader.
0xC	4	Index of first shader binary (base_index)
0x10		Null-terminated name string
		Shader variation section (possible values)
		Shader variation section (symbols / default values)
		Shader symbol section (uniform vars)
		Shader symbol section (uniform blocks)
		Shader symbol section (sampler vars)
		Shader symbol section (attrib vars)

Shader Variation Section

A single shader program may have different variations. Variations are defined by a set of macros, each of which can be set to a predefined set of values. Every possible combination of macro values has its own shader binaries, so the number of shader binaries in a program grows exponentially with its number of variation macros. This is why some sharcfb files are much bigger than others.

Each shader program has two shader variation sections. The first one defines the list of possible values for each shader macro. The second section only has one value per macro: its default value.

Offset	Size	Description
0x0	4	Size of this section
0x4	4	Number of variation macros
0x8		Variations macros

The following algorithm can be used to find the shader binary index of a specific variation:

def get_variation_index(base_index, shader_program, settings):
    index = 0
    for macro in shader_program.variation_macros:
        index *= len(macro.possible_values)
        index += macro.possible_values.index(settings[macro.name])
    
    if shader_program.has_geometry_shader:
        return base_index + index * 3
    return base_index + index * 2

Now load the vertex shader from variation_index, the pixel shader from variation_index + 1 and the geometry shader from variation_index + 2 (if it exists).

Variation Macro

Offset	Size	Description
0x0	4	Size (or offset to next variation macro)
0x4	4	Length of macro name
0x8	4	Number of values
0xC	4	Length of symbol name
0x10		Variation macro name (null-terminated)
		List of values. These are null-terminated strings stored directly after each other (without padding)
		Symbol name (null-terminated)

Shader Symbol Section

Offset	Size	Description
0x0	4	Size of this section
0x4	4	Number of shader symbols
0x8		Shader symbols

Shader Symbol

Offset	Size	Description
0x0	4	Size (or offset to next shader symbol)
0x4	4	Shader variable size
0x8	4	Length of variable name
0xC	4	Length of symbol name
0x10	4	Size of default value
0x14	4	Number of shader variations
0x18		Variable name (null-terminated)
		Symbol name (null-terminated)
		Default value
		For each shader variation, a bool (one byte) indicating whether this variable is used by that variation