Adding watermark

Create a document with a watermark with custom settings:

• create an empty page with a watermark (Api, ApiDocument/InsertWatermark);
• edit watermark settings, set an image, specify size, direction and opacity (ApiWatermarkSettings);

let doc = Api.GetDocument();
doc.InsertWatermark("Watermark", true);
let settings = doc.GetWatermarkSettings();
settings.SetType("image");
settings.SetImageURL("https://static.onlyoffice.com/assets/docs/samples/img/onlyoffice_logo.png");
settings.SetImageSize(40 * 36_000, 40 * 36_000);
settings.SetDirection("horizontal");
settings.SetOpacity(100);
doc.SetWatermarkSettings(settings);