type TDrawMode = (dmOpaque, dmBlend, dmCustom, dmTransparent);
Description
TDrawMode defines how the bitmap
is combined with the background. This is the type for DrawMode
property of TBitmap32 class, and
it is also passed as parameter in BlockTransfer
and StretchTransfer
functions.
- dmOpaque – a color information from the foreground image
completely replaces the background data;
- dmBlend – foreground and background colors are blended
together using per-pixel opacity of the foreground bitmap (stored in its alpha
channel), multiplied by its MasterAlpha;
- dmCustom – colors are mixed using OnPixelCombine
event, that is essentially a call-back function allowing for any custom blending
routine.
- dmTransparent – color key transparency: any pixel that
matches TBitmap32.OuterColor
is treated as transparent.