SoftMask Property (PdfImageResource)
Gets or sets a soft-mask image which must be used as a source of mask shape or mask opacity values in the transparent imaging model.
The alpha source parameter in the graphics state determines whether the mask values are interpreted as shape or opacity. If present, this property overrides the current soft mask in the graphics state, as well as the image's Mask entry, if any. However, the other transparency-related graphics state parameters-blend mode and alpha constant-remain in effect.
Target Platforms: .NET9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5