Microsoft DirectX 8.0 (Visual Basic)

Output Write Masks

The output masks supported by the Direct3DX pixel shader compiler are used to indicate whether this result should update either the color or the alpha component of the result, and therefore whether to use the color or alpha pipelines for its processing. These output masks are analogous to the separate color and alpha operations in Microsoft® DirectX 6.0 and 7.0 multitexture blending.

These flags are not as general as those supported by vertex shaders because the rgb components are always grouped into a single flag, resulting in only two different masks, .a and .rgb.

The following output write masks are supported.

Note that none of the output write masks are supported for the texture addressing instruction. These operations always update all four components of the destination register, you cannot separate r, g, and b individually.

The pixel shader does not support arbitrary swizzles, only color and alpha operations.