Add a highlight annotation to a PDF in Go

To add a highlight annotation to a PDF Document page.

doc := NewPDFDoc(filename)
page := doc.GetPage(1)

// Create a highlight
hl := HighlightAnnotCreate( doc.GetSDFDoc(), NewRect(100.0, 490.0, 150.0, 515.0) )
hl.SetColor( NewColorPt(0.0,1.0,0.0), 3 )
hl.RefreshAppearance()
page.AnnotPushBack( hl )

Add or edit PDF annotations sample
Full code sample which shows how to add or edit PDF annotations (e.g. hyperlink, intra-document link, stamp, rubber stamp, file attachment, sound, text, free-text, line, circle, square, polygon, polyline, highlight, squiggly, caret, and ink).