Source Parameter Token
A source parameter token describes properties of a source register and is composed of the following bits:
Bits
[10:00] Bits 0 through 10 indicate the register number (offset in register file).
[12:11] Bits 11 and 12 are the fourth and fifth bits [3,4] for indicating the register type.
[13] For a pixel shader (PS) versions earlier than 3_0, bit 13 is reserved and set to 0x0.
For pixel shader (PS) version 3_0 and later and all versions of vertex shader (VS), bit 13 indicates whether relative addressing mode is used. If set to 1, relative addressing applies.
[15:14] Reserved for all versions of PS and VS. This value is set to 0x0.
[23:16] Bits 16 through 23 indicate channel swizzle. All arithmetic operations are performed in four (X,Y,Z,W) parallel channels. Swizzle specifies which source component participates in a channel of operation. For more information about swizzle, see the latest DirectX SDK documentation. The bits of this field specify swizzle for the following channels:
| Bits | Channel |
|---|---|
17:16 |
Channel X swizzle |
19:18 |
Channel Y swizzle |
21:20 |
Channel Z swizzle |
23:22 |
Channel W swizzle |
The following values in any set of preceding bits specify the source component to be used in the channel of operation:
| Value | Component |
|---|---|
0x0 |
Component X is used. |
0x1 |
Component Y is used. |
0x2 |
Component Z is used. |
0x3 |
Component W is used. |
For example, if the 19:18 bits are set to 0x2, then component Z is used as the source for the channel Y operation.
[27:24] Bits 24 through 27 indicate the source modifier. This 4-bit value indicates the following source modifier types:
| Value | Source modifier type |
|---|---|
0x0 |
None |
0x1 |
Negate |
0x2 |
Bias |
0x3 |
Bias and negate |
0x4 |
Sign (bx2) |
0x5 |
Sign (bx2) and negate |
0x6 |
Complement |
0x7 |
x2 (PS 1_4) |
0x8 |
x2 and negate (PS 1_4) |
0x9 |
dz (divide through by Z component - PS 1_4) |
0xa |
dw (divide through by W component − PS 1_4) |
0xb |
abs(x) compute absolute value |
0xc |
-abs(x) compute absolute value and negate |
0xd |
NOT. Applied only to the predication register, which is BOOL. Therefore, it is logical NOT. |
0xe-0xf |
Reserved |
[30:28] Bits 28 through 30 are the first three bits [0,1,2] for indicating the register type.
[31] Bit 31 is 0x1.
Comments
Bits 28, 29, 30, 11, and 12 form a 5-bit value that indicates the register type. For information about register types, see Shader Register Types.
Requirements
Available in Windows Vista and later versions of the Windows operating systems.