DXCOMPFUNC enumeration

Describes the method used for compositing by the Compositor transform.

Syntax

typedef enum DXCOMPFUNC { 
  DXCOMPFUNC_SWAP_AB       = 0x10,
  DXCOMPFUNC_FUNCMASK      = 0xF,
  DXCOMPFUNC_CLEAR         = 0,
  DXCOMPFUNC_MIN,
  DXCOMPFUNC_MAX,
  DXCOMPFUNC_A,
  DXCOMPFUNC_A_OVER_B,
  DXCOMPFUNC_A_IN_B,
  DXCOMPFUNC_A_OUT_B,
  DXCOMPFUNC_A_ATOP_B,
  DXCOMPFUNC_A_SUBTRACT_B,
  DXCOMPFUNC_A_ADD_B,
  DXCOMPFUNC_A_XOR_B,
  DXCOMPFUNC_B             = ( DXCOMPFUNC_A | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_OVER_A      =  ( DXCOMPFUNC_A_OVER_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_IN_A        =  ( DXCOMPFUNC_A_IN_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_OUT_A       =  ( DXCOMPFUNC_A_OUT_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_ATOP_A      =  ( DXCOMPFUNC_A_ATOP_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_SUBTRACT_A  =  ( DXCOMPFUNC_A_SUBTRACT_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_B_ADD_A       = ( DXCOMPFUNC_A_ADD_B | DXCOMPFUNC_SWAP_AB ),
  DXCOMPFUNC_NUMFUNCS
} DXCOMPFUNC;

Constants

• DXCOMPFUNC_SWAP_AB
  A flag used internally to switch the inputs for A and B.

• DXCOMPFUNC_FUNCMASK
  A bitmask used to check for valid input.

• DXCOMPFUNC_CLEAR
  The transform should perform no operation on the output.

• DXCOMPFUNC_MIN
  Compares the brightness of each sample in both images, and shows only the less bright of the two samples.

• DXCOMPFUNC_MAX
  Compares the brightness of each sample in both images, and shows only the brighter of the two samples.

• DXCOMPFUNC_A
  The transform should write Image A to the output.

• DXCOMPFUNC_A_OVER_B
  The transform should place Image A over Image B. All of Image A will be visible, and Image B will show through any zero alpha regions of Image A.

• DXCOMPFUNC_A_IN_B
  For the resulting image, all parts of Image A that are contained in Image B show. Only regions with nonzero alpha for both images will be visible, and no part of Image B will show through.

• DXCOMPFUNC_A_OUT_B
  For the resulting image, all parts of Image B that are contained in Image A are removed. Areas in Image B with zero alpha are not cut out of Image A.

• DXCOMPFUNC_A_ATOP_B
  For the resulting image, Image A is placed over Image B, with each sample scaled by the alpha channel of Image B.

• DXCOMPFUNC_A_SUBTRACT_B
  For the resulting image, the sample color values of Image B are subtracted from the corresponding sample color values of Image A. The resulting color is scaled by the alpha values of Image A.

• DXCOMPFUNC_A_ADD_B
  For the resulting image, the sample color values of Image B are added to the corresponding sample color values of Image A. The resulting color value is scaled by the alpha value of Image A.

• DXCOMPFUNC_A_XOR_B
  For the resulting image, places where the two images do not overlap show as normal. Places that do overlap are scaled by their inverse value for alpha.

• DXCOMPFUNC_B
  The transform should write Image B to the output.

• DXCOMPFUNC_B_OVER_A
  The same operation as DXCOMPFUNC_A_OVER_B, with Image A and B switched.

• DXCOMPFUNC_B_IN_A
  The same operation as DXCOMPFUNC_A_IN_B, with Image A and B switched.

• DXCOMPFUNC_B_OUT_A
  The same operation as DXCOMPFUNC_A_OUT_B, with Image A and B switched.

• DXCOMPFUNC_B_ATOP_A
  The same operation as DXCOMPFUNC_A_ATOP_B, with Image A and B switched.

• DXCOMPFUNC_B_SUBTRACT_A
  The same operation as DXCOMPFUNC_A_SUBTRACT_B, with Image A and B switched.

• DXCOMPFUNC_B_ADD_A
  The same operation as DXCOMPFUNC_A_ATOP_B, with Image A and B switched.

• DXCOMPFUNC_NUMFUNCS
  The number of supported compositing operations, used for parameter validation.

Remarks

The transform requires two inputs and one output, which are defined by calling the IDXTransform::Setup method. In the following material, Image A corresponds to setup input index 0, and Image B to setup input index 1. The composite operation combines the samples of Image A and Image B according to one of the listed methods. Each one corresponds to a different order of overlaying the images or a different way of combining the sample colors using each image's alpha channel.

Requirements