Write Image as Standard camera views in Ruby

Developers Ruby API
11 
def save_view_to_png()
  #
  path = UI.savepanel("Save PNG Image As","write_image.png")
  return unless path
  view = Sketchup.active_model.active_view
  view.write_image(
    filename: path,
    width:    view.vpwidth,
    height:   view.vpheight,
    antialias:   true,
    transparent: true
  )
  #
end

But as @dezmo shows you can specify many more PDF export options
by using Sketchup::Model#export() (see the exports options for PDF document.)