NAME
        SetFont -- Set the text font and attributes in a rastport.

   SYNOPSIS
        SetFont(rp, font)
                A1   A0

        void SetFont(struct rastport *, struct textfont *);

   FUNCTION
        This function sets the font in the rastport to that described
        by font, and updates the text attributes to reflect that
        change.  This function clears the effect of any previous
        soft styles.

   INPUTS
        rp   - the rastport in which the text attributes are to be changed
        font - pointer to a textfont structure returned from openfont()
               or opendiskfont()

   RESULT

   NOTES
        This function had previously been documented that it would
        accept a null font.  This practice is discouraged.
        o   Use of a rastport with a null font with text routines has
            always been incorrect and risked the guru.
        o   Keeping an obsolete font pointer in the rastport is no more
            dangerous than keeping a zero one there.
        o   SetFont(rp, 0) causes spurious low memory accesses under
            some system software releases.

        As of V36, the following Amiga font variants are no longer
        directly supported:
            fonts with NULL tf_CharSpace and non-NULL tf_CharKern.
            fonts with non-NULL tf_CharSpace and NULL tf_CharKern.
            fonts with NULL tf_CharSpace and NULL tf_CharKern with
                a tf_CharLoc size component greater than tf_XSize.
        Attempts to SetFont these one of these font variants will
        cause the system to modify your font to make it acceptable.

   BUGS
        Calling SetFont() on in-code TextFonts (ie fonts not
        OpenFont()ed) will result in a loss of 24 bytes from
        the system as of V36.
        This can be resolved by calling stripfont().

   SEE ALSO
        openfont()  stripfont()
        diskfont.library/opendiskfont()  graphics/text.h