This page describes the structure of the buffer for GX command 1 with the registers at 0x1EF018E0. This buffer is used for GPU commands including OpenGL commands, each 8-byte entry in the buffer is a command. Cmd+0 is the command parameter, and cmd+4 is the command header.
Command Header
| Bit
|
Description
|
| 19-0
|
Command ID
|
| 30-20
|
Total words following the command, if any.
|
| 31
|
?
|
The first word in the parameter data structure is the command parameter value, the rest of the data structure is from the data following the command. The word after the last data structure word is padding when needed for 8-byte alignment, for the following command.
Commands
| CommandID
|
Parameter
|
Description
|
| 0x000F0010
|
Value is 0x12345678
|
This command is always the last command in the buffer.
|
| 0x000F0110
|
Value 0x1
|
This command is immediately before CmdID 0x000F0010, this is used elsewhere in the buffer as well.
|
| 0x000F0111
|
Value 0x1
|
This command is immediately before CmdID 0x000F0110, however CmdID 0x000F0110 doesn't always follow this command.
|
| 0x000F0040
|
u32, valid values are 0x1 and 0x2, values 0x0 and 0x3 have the same effect as value 0x2. Only bits 1-0 are used.
|
Disable/enable alpha testing. Parameter value 0x1 disables GL_ALPHA_TEST, while value 0x2 enables GL_ALPHA_TEST.
|
| 0x000F0041
|
float Z vector
|
This sets Z scaling for the current matrix.
|
| 0x000F0042
|
float Y vector
|
This sets Y scaling for the current matrix.
|
| 0x000F0043
|
float unknown
|
?
|
| 0x000F0044
|
float X vector
|
This sets X scaling for the current matrix.
|
| 0x801F004D
|
First word in parameter structure
|
?
|
| 0x000F006E
|
u32
|
This is used immediately after CmdID 0x000F011E, with the same input parameter value as CmdID 0x000F011E.
|
| 0x000F011E
|
u32
|
This sets the width and height for the framebuffer used for rendering. Therefore this is glViewport() with x=0 and y=0.
|
| 0x000F02C0
|
0x80000000 | Type
|
This is used immediately before CmdID 0xXXXF02C1. This type field controls the command parameter buffer type.
|
| 0xXXXF02C1
|
First word in the first entry
|
A list of entries follow this command.
|
Parameter value format for CmdID 0x000F011E
| Bit
|
Description
|
| 11-0
|
Framebuffer width
|
| 23-12
|
Framebuffer height - 1
|
| 24
|
Must be set
|
| 31-25
|
Unused?
|
Normally the width and height is set to the same dimensions used with GX command 3 and 4.
Entries for CmdID 0xXXXF02C1
| Index Word
|
Description
|
| 0
|
float
|
| 1
|
float
|
| 2
|
float
|
Color Entry
| Index Word
|
Description
|
| 0
|
float Red component
|
| 1
|
float Blue component
|
| 2
|
float Green component
|
| 3
|
float Alpha?
|
| 4
|
float
|
| 5
|
float
|
Vertex Entry
| Index Word
|
Description
|
| 0
|
float X coordinate
|
| 1
|
float Y coordinate
|
| 2
|
float Z coordinate
|
Types for CmdID 0x000F02C0
| Value
|
Entries per chunk
|
Description
|
| 0x00
|
4
|
Related to matrix translation?
|
| 0x04
|
4
|
Unknown, this is used immediately after type 0x00.
|
| 0x08
|
One color entry via two CmdID 0xXXXF02C1 entries.
|
Sets the color.
|
| 0x0A
|
4
|
Texture related?
|
| 0x0B
|
3
|
?
|
| 0x14
|
<=30
|
Geometry vertices
|
| 0x4C
|
4
|
?
|
| 0x50, 0x53, and 0x56
|
1
|
?
|
| 0x51, 0x54, and 0x57
|
1
|
?
|
| 0x52, 0x55, and 0x58
|
1
|
?
|
| 0x59
|
1
|
Unknown, the entry data is floats converted from s32s.
|
| 0x5A
|
2
|
Color related?
|
| 0x5C
|
1
|
?
|