Character underlining

The baseline offset for underlining is measured downwards from the baseline. It is the number of pixels from the baseline to the top of the underline. The underline width is the number of pixel rows used for the underline. For example, if the underlining baseline offset is zero and the underline width is one then the underline will occupy the pixel row immediately below the baseline, (font: Times New Roman, 20 pixel, Bold Italic Proportional):