CONST_D3DTEXTUREOP

Defines per-stage texture-blending operations.

Enum CONST_D3DTEXTUREOP
    D3DTOP_DISABLE                   =  1
    D3DTOP_SELECTARG1                =  2
    D3DTOP_SELECTARG2                =  3
    D3DTOP_MODULATE                  =  4
    D3DTOP_MODULATE2X                =  5
    D3DTOP_MODULATE4X                =  6
    D3DTOP_ADD                       =  7
    D3DTOP_ADDSIGNED                 =  8
    D3DTOP_ADDSIGNED2X               =  9
    D3DTOP_SUBTRACT                  = 10
    D3DTOP_ADDSMOOTH                 = 11
    D3DTOP_BLENDDIFFUSEALPHA         = 12
    D3DTOP_BLENDTEXTUREALPHA         = 13
    D3DTOP_BLENDFACTORALPHA          = 14
    D3DTOP_BLENDTEXTUREALPHAPM       = 15
    D3DTOP_BLENDCURRENTALPHA         = 16 (&H10)
    D3DTOP_PREMODULATE               = 17 (&H11)
    D3DTOP_MODULATEALPHA_ADDCOLOR    = 18 (&H12)
    D3DTOP_MODULATECOLOR_ADDALPHA    = 19 (&H13)
    D3DTOP_MODULATEINVALPHA_ADDCOLOR = 20 (&H14)
    D3DTOP_MODULATEINVCOLOR_ADDALPHA = 21 (&H15)
    D3DTOP_BUMPENVMAP                = 22 (&H16)
    D3DTOP_BUMPENVMAPLUMINANCE       = 23 (&H17)
    D3DTOP_DOTPRODUCT3               = 24 (&H18)
    D3DTOP_MULTIPLYADD               = 25 (&H19)
    D3DTOP_LERP                      = 26 (&H1A)
End Enum

Constants

Control members

D3DTOP_DISABLE

Disables output from this texture stage and all stages with a higher index. To disable texture mapping, set this as the color operation for the first texture stage (stage 0). Alpha operations cannot be disabled when color operations are enabled. Setting the alpha operation to D3DTOP_DISABLE when color blending is enabled causes undefined behavior.

D3DTOP_SELECTARG1

Use this texture stage's first color or alpha argument, unmodified, as the output. This operation affects the color argument when used with the D3DTSS_COLOROP texture-stage state, and the alpha argument when used with D3DTSS_ALPHAOP.

D3DTOP_SELECTARG2

Use this texture stage's second color or alpha argument, unmodified, as the output. This operation affects the color argument when used with the D3DTSS_COLOROP texture stage state, and the alpha argument when used with D3DTSS_ALPHAOP.

Modulation members

D3DTOP_MODULATE

Multiply the components of the arguments.

D3DTOP_MODULATE2X

Multiply the components of the arguments, and shift the products to the left 1 bit (effectively multiplying them by 2) for brightening.

D3DTOP_MODULATE4X

Multiply the components of the arguments, and shift the products to the left 2 bits (effectively multiplying them by 4) for brightening.

Addition and subtraction members

D3DTOP_ADD

Add the components of the arguments.

D3DTOP_ADDSIGNED

Add the components of the arguments with a –0.5 bias, making the effective range of values from –0.5 through 0.5.

D3DTOP_ADDSIGNED2X

Add the components of the arguments with a –0.5 bias, and shift the products to the left 1 bit.

D3DTOP_SUBTRACT

Subtract the components of the second argument from those of the first argument.

D3DTOP_ADDSMOOTH

Add the first and second arguments; then subtract their product from the sum.

Linear alpha blending members

D3DTOP_BLENDDIFFUSEALPHA, D3DTOP_BLENDTEXTUREALPHA, D3DTOP_BLENDFACTORALPHA, and D3DTOP_BLENDCURRENTALPHA

Linearly blend this texture stage, using the interpolated alpha from each vertex (D3DTOP_BLENDDIFFUSEALPHA), alpha from this stage's texture (D3DTOP_BLENDTEXTUREALPHA), a scalar alpha (D3DTOP_BLENDFACTORALPHA) set with the D3DRS_TEXTUREFACTOR render state, or the alpha taken from the previous texture stage (D3DTOP_BLENDCURRENTALPHA).

D3DTOP_BLENDTEXTUREALPHAPM

Linearly blend a texture stage that uses a premultiplied alpha.

Specular mapping members

D3DTOP_PREMODULATE

Modulate this texture stage with the next texture stage.

D3DTOP_MODULATEALPHA_ADDCOLOR

Modulate the color of the second argument, using the alpha of the first argument; then add the result to argument one. This operation is supported only for color operations (D3DTSS_COLOROP).

D3DTOP_MODULATECOLOR_ADDALPHA

Modulate the arguments; then add the alpha of the first argument. This operation is supported only for color operations (D3DTSS_COLOROP).

D3DTOP_MODULATEINVALPHA_ADDCOLOR

Similar to D3DTOP_MODULATEALPHA_ADDCOLOR, but use the inverse of the alpha of the first argument. This operation is supported only for color operations (D3DTSS_COLOROP).

D3DTOP_MODULATEINVCOLOR_ADDALPHA

Similar to D3DTOP_MODULATECOLOR_ADDALPHA, but use the inverse of the color of the first argument. This operation is supported only for color operations (D3DTSS_COLOROP).

Bump-mapping members

D3DTOP_BUMPENVMAP

Perform per-pixel bump mapping, using the environment map in the next texture stage, without luminance. This operation is supported only for color operations (D3DTSS_COLOROP).

D3DTOP_BUMPENVMAPLUMINANCE

Perform per-pixel bump mapping, using the environment map in the next texture stage, with luminance. This operation is supported only for color operations (D3DTSS_COLOROP).

D3DTOP_DOTPRODUCT3

Modulate the components of each argument as signed components, add their products; then replicate the sum to all color channels, including alpha. This operation is supported for color and alpha operations.

In DirectX 6.0 and 7.0 multitexture operations the above inputs are all shifted down by half (y = x - 0.5) before use to simulate signed data, and the scalar result is automatically clamped to positive values and replicated to all three output channels. Also, note that as a color operation this does not updated the alpha it just updates the RGB components.

However, in DirectX 8.x shaders, you can specify that the output be routed to the .rgb or the .a components or both (the default). You can also specify a separate scalar operation on the alpha channel.

Triadic texture blending members

D3DTOP_MULTIPLYADD

Performs a multiply-accumulate operation. It takes the last two arguments, multiplies them, adds them to the remaining input/source argument, and then places this sum into the result.

S_RGBA = Arg1 + Arg2 * Arg3

D3DTOP_LERP

Linearly interpolates between the 2nd and 3rd source arguments by a proportion specified in the 1st source argument.

S_RGBA = (Arg1) * Arg2 + (1-Arg1) * Arg3

Remarks

The members of this type are used when setting color or alpha operations by using the D3DTSS_COLOROP or D3DTSS_ALPHAOP texture stage state values with the Direct3DDevice8.SetTextureStageState method.

In the above formulas, S_RGBA is the RGBA color produced by a texture operation, and Arg1 and Arg2 represent the complete RGBA color of the texture arguments. Individual components of an argument are shown with subscripts. For example, the alpha component for argument 1 would be shown as Arg1_A.

See Also

CONST_D3DTEXTURESTAGESTATETYPE