Calculates the width of a glyph in points if it was output in the given font and font size. This function needs an Adobe font metrics file to calculate the precise width.
Resource identifier of the postscript file as returned by ps_new.
The position of the glyph in the font encoding vector.
The identifier of the font to be used. If not font is specified the current font will be used.
The size of the font. If no size is specified the current size is used.
The width of a glyph in points.