code: func (f *Fpdf) SetLineCapStyle(styleStr string) {
  	var capStyle int
  	switch styleStr {
  	case "round":
  		capStyle = 1
  	case "square":
  		capStyle = 2
  	default:
  		capStyle = 0
  	}
  	f.capStyle = capStyle
  	if f.page > 0 {
  		f.outf("%d J", f.capStyle)
  	}
  }
docs: // SetLineCapStyle defines the line cap style. styleStr should be "butt",
  // "round" or "square". A square style projects from the end of the line. The
  // method can be called before the first page is created. The value is
  // retained from page to page.