PdfTemplate template = writer.getDirectContent().createTemplate(20, 20);
BaseFont bf = BaseFont.createFont("Helvetica", "winansi", false);
String text = "Vertical";
float size = 16;
float width = bf.getWidthPoint(text, size);
template.beginText();
template.setRGBColorFillF(1, 1, 1);
template.setFontAndSize(bf, size);
template.setTextMatrix(0, 2);
template.showText(text);
template.endText();