Transparent Blitting

DIVE transparent blitting functions enable an interactive game or imaging application to create composites of graphics and image data using a transparency key color.

To set up for transparent blitting, the application calls DiveSetTransparentBlitMode before it calls DiveSetupBlitter.

ULONG APIENTRY DiveSetTransparentBlitMode (HDIVE hDiveInst,
                                           ULONG ulTransBlitMode,
                                           ULONG ulValue1,
                                           ULONG ulValue2);

The following transparent blitting modes can be specified for ulTransBlitMode:

• DIVE_TBM_NONE
  
• DIVE_TBM_EXCLUDE_SOURCE_VALUE
  
• DIVE_TBM_EXCLUDE_SOURCE_RGB_RANGE
  
• DIVE_TBM_INCLUDE_SOURCE_RGB_RANGE
  
• DIVE_TBM_EXCLUDE_SOURCE_YUV_RANGE
  
• DIVE_TBM_INCLUDE_SOURCE_YUV_RANGE

Transparent blitting functions are based on source pixel values. If the pixel value in the source image buffer is the key color, the value of the corresponding pixel in the destination buffer is not modified. Interpretation of color values specified in ulValue1 and ulValue2 parameters is dependent on the source image color format specified in the fccSrcColorFormat field of the SetupBlitter structure and the transparent blitting mode.