Microsoft DirectX 8.0 (Visual Basic) |
This section contains reference information for the registers implemented by the Direct3DX pixel shader assembler.
Name | I/0 Permissions | Minimum Count | Maximum Count per Instruction | Source |
---|---|---|---|---|
cn | read-only | 8 | 2 | API call |
rn | read/write | 2 | 2 | Written |
tn | read/write | 4 | 1 | Textures |
vn | read-only | 2 | 1 | Vertex Colors |
The minimum count column indicates the minimum number of registers that the implementation must support in order to be able to expose Microsoft® DirectX® 8.0 shading capability.
The maximum count per instruction column indicates the maximum number of registers supported in any one instruction. This includes source parameter read ports for an instruction. The destination parameter of an instruction does not apply towards the limit.
Each register is a four-component vector, whose components range from –1.0 to 1.0, with at least 8 bits of precision per component. Unlike the vertex shader assembler, the pixel shader assembler does not have any output registers; rather, the pixel shader just emits r0.