SHBIN

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The SHBIN (SHader BINary) format is used to contain compiled and linked shader programs. These can include vertex shaders and geometry shaders. In commercial applications, SHBIN files can be found as standalone files with the extension .shbin, or within container formats like, for example, CGFX (with the extension .bcsdr). They are typically compiled from .vsh files, .gsh files, and sometimes .asm files.

A SHBIN's structure starts with a binary header (DVLB), then a single program header (DVLP), then one or more executable headers DVLE(s). The binary header specifies the number and location of DVLEs. The program header specifies the generic parts of the shader (i.e. the shader program data, the operand descriptor data, and a filename symbol table). The executable headers specify the contextual details (i.e. entry point, constant values, debug symbols, etc). There may be multiple executable headers, so in this sense multiple shaders sharing the same program code can be stored in a single SHBIN. Hence for the following, note the distinction between "program" and "executable".

For a description of the instruction set, see the following page : Shader Instruction Set

Header[edit]

Offset Size Description
0x0 0x4 Magic "DVLB"
0x4 0x4 N = number of DVLEs in SHBIN
0x8 0x4*N DVLE offset table; each offset is a u32 relative to the start of the DVLB section

The DVLP section comes directly after the binary header.

DVLP[edit]

Offset Size Description
0x0 0x4 Magic "DVLP"
0x4 0x4 Unknown, same value as in DVLE. (Likely a version number)
0x8 0x4 Offset (relative to DVLP start) to the compiled shader binary blob
0xC 0x4 Size of compiled shader binary blob, in words
0x10 0x4 Offset (relative to DVLP start) to operand descriptor table
0x14 0x4 Number of operand descriptor table entries (each entry is 8-bytes long)
0x18 0x4 Unknown (Same value as offset to filename symbol table?)
0x1C 0x4 Unknown (Always zero?)
0x20 0x4 Offset (relative to DVLP start) to filename symbol table
0x24 0x4 Size of filename symbol table

DVLE[edit]

Offset Size Description
0x0 0x4 Magic "DVLE"
0x4 0x2 Unknown, same value as in DVLP. (Likely a version number)
0x6 0x1 Shader type (0x0 = vertex shader, 0x1 = geometry shader; might contain other flags)
0x7 0x1 true = merge vertex and geometry shader outmaps (geometry shader)
0x8 0x4 Executable's main offset in binary blob (in words)
0xC 0x4 Executable's program's endmain offset in binary blob (in words)
0x10 0x2 Bitmask of used input registers
0x12 0x2 Bitmask of used output registers
0x14 0x1 Geometry shader type (point = 0x0, variable/subdivide = 0x1, fixed/particle = 0x2)
0x15 0x1 Starting float constant register number for storing the fixed-size primitive vertex array (geometry shader, fixed mode)
0x16 0x1 Number of fully-defined vertices in the variable-size primitive vertex array (geometry shader, variable mode)
0x17 0x1 Number of vertices in the fixed-size primitive vertex array (geometry shader, fixed mode)
0x18 0x4 Offset (relative to DVLE start) to constant table
0x1C 0x4 Number of entries in constant table (each entry is 0x14-byte long)
0x20 0x4 Offset (relative to DVLE start) to label table
0x24 0x4 Number of entries in label table (each entry is 0x10-byte long)
0x28 0x4 Offset (relative to DVLE start) to output register table
0x2C 0x4 Number of entries in output register table (each entry is 0x8-byte long)
0x30 0x4 Offset (relative to DVLE start) to uniform table
0x34 0x4 Number of entries in uniform table (each entry is 0x8-byte long)
0x38 0x4 Offset (relative to DVLE start) to symbol table
0x3C 0x4 Size of symbol table (in bytes)

Label Table Entry[edit]

Offset Size Description
0x0 0x2 Label ID
0x0 0x2 Unknown (always 1?)
0x4 0x4 Offset (relative to shader program blob start) to label's location, in words
0x8 0x4 Size of label's location (in words). 0xFFFFFFFF/(uint32_t)-1 if there is no size.
0xC 0x4 Offset (relative to DVLE symbol table start) to label's symbol

Constant Table Entry[edit]

Each executable's constants are stored in a constant table. This information is used by ctrulib's SHDR framework to automatically send those values to the GPU when changing to a given program. An entry is constituted by a header and the constant data, the latter of which uses a format specific to the constant type.

Offset Size Description
0x0 0x1 Constant type (0=bool, 1=ivec4, 2=vec4)
0x2 0x1 Constant register ID

Corresponding constant entry formats:

Offset Size Description
0x0 0x1 0x0
0x2 0x1 Boolean constant register ID
0x4 0x1 Value (boolean)
Offset Size Description
0x0 0x1 0x1
0x2 0x1 Integer constant register ID
0x4 0x1 x (u8)
0x5 0x1 y (u8)
0x6 0x1 z (u8)
0x7 0x1 w (u8)
Offset Size Description
0x0 0x1 0x2
0x2 0x1 floating-point constant register ID
0x4 0x4 x (float24)
0x8 0x4 y (float24)
0xC 0x4 z (float24)
0x10 0x4 w (float24)

Output Table Entry[edit]

Offset Size Description
0x0 0x2 Output type (see table below)
0x2 0x2 Register ID
0x4 0x2 Output attribute component mask (e.g. 5=xz)
0x6 0x2 Unknown (Consistently the same number throughout the DVLE, may vary between DVLEs?)

Output types :

Type Description
0x0 result.position
0x1 result.normalquat
0x2 result.color
0x3 result.texcoord0
0x4 result.texcoord0w
0x5 result.texcoord1
0x6 result.texcoord2
0x7 ?
0x8 result.view

Uniform Table Entry[edit]

Keep in mind that the usage of the term "Uniform" here is used as defined by Nvidia (variable who obtains its initial value from an external environment) and not as defined by RenderMan/GLSL (variables whose values are constant over a shaded surface).

The uniform table contains a list of all registers whose initial values are derived by an external source along with their layout and associated symbol.

Offset Size Description
0x0 0x4 Offset (relative to DVLE symbol table start) to variable's symbol
0x4 0x2 Register index of the start of the uniform
0x6 0x2 Register index of the end of the uniform (equal to start register for non-arrays)

The register indices refer to a unified register space for non-output registers. The mapping of register index values to registers is the following:

Values Registers
0x00-0x0F v0-v15
0x10-0x6F c0-c95
0x70-0x73 i0-i3
0x78-0x87 b0-b15

DVOJ[edit]

There is another file format for shaders, which starts with the string "DVOJ". This format seems to be used for unlinked shader objects. It seems likely that one or multiple DVOJs can be linked to a DVLB file, similarly to the C compilation model.

Structurally, a DVOJ header captures all information there is about a single shader instance. It uses the same fields like the DVLB, DVLP, and DVLE structures, but also stores two unknown blocks of data. It seems that the entry point of a DVOJ is always the first shader instruction.

All offsets in the following table are given relative to the DVOJ start.

Offset Size Description
0x00 0x4 Magic "DVOJ"
0x04 0x4 Unknown. Seems to be related to the DVLE shader type.
0x08 0x4 Unknown.
0x0C 0x4 Padding? (usually 0xFFFFFFFF)
0x10 0x4 Offset to constant table
0x14 0x4 Number of entries in constant table (each entry is 0x14-byte long)
0x18 0x4 Offset to label table
0x1C 0x4 Number of entries in label table (each entry is 0x10-byte long)
0x20 0x4 Offset to the compiled shader binary blob
0x24 0x4 Size of compiled shader binary blob, in words
0x28 0x4 Offset (relative to DVLP start) to shader instruction extension table
0x2C 0x4 Number of shader instruction extension table entries (each entry is 8-byte long)
0x30 0x4 Offset to unknown block 1
0x34 0x4 Number of items in unknown block 1 (each item is 8-byte long). This seems to be equal to the total number of instructions.
0x38 0x4 Offset to unknown block 2
0x3C 0x4 Number of items in unknown block 2 (each item is 12-byte long). This seems to be equal to the number of instructions taking arguments (i.e. excluding NOP, END, ...)
0x40 0x4 Offset to output register table
0x44 0x4 Number of entries in output register table (each entry is 0x8-byte long)
0x48 0x4 Offset to uniform table
0x4C 0x4 Number of entries in uniform table (each entry is 0x8-byte long)
0x50 0x4 Offset to symbol table
0x54 0x4 Size of symbol table (in bytes)


Unknown Block 1 Item[edit]

A wild guess is that this denotes shader source line information. Take the information with a grain of salt, though, since it hasn't been backed by any empirical data so far.

The index N of the item within Unknown Block 1 corresponds to the Nth instruction in the shader binary.

Offset Size Description
0x0 0x4 Byte offset within symbol table pointing to a source shader filename.
0x4 0x4 Line number of the corresponding shader instruction within the shader source code.

Unknown Block 2 Item[edit]

Offset Size Description
0x0 0x4 This seems to be an index of a shader instruction. All non-nullary instructions seem to be referenced exactly once.
0x4 0x4
0x8 0x4