Gets or sets the bounds of this WatermarkImage in the Watermark.
The TopLeft position is relative to the Watermark.
The Watermark also has a Placement property to position and size the Watermark and its content.
Gets or sets the opacity of the WatermarkImage.
The final opacity of the watermark content will be a combination of
WatermarkDefinition.Opacity, Watermark.Opacity and (WatermarkImage.Opacity or WatermarkText.TextStyle.Brush.Opacity).
0 is transparent, 1 is opaque.
Gets or sets the rotation angle in degrees of this WatermarkImage.
The final RotationAngle will be a combination of
WatermarkDefinition.RotationAngle, Watermark.RotationAngle and (WatermarkImage.RotationAngle or WatermarkText.TextStyle.RotationAngle).
0 is no rotation, 90 is 90 degrees to the left.
