The STXT chunk contains a text string along with some information on
how and where to render the text.

    struct STXTstruct {
        ULONG       ID;
        ULONG       Size;
        UBYTE       Pad0;           /* Always 0 (for future expansion) */
        UBYTE       WhichFont;      /* Which font to use */
        IEEE        CharW, CharH,   /* W/H of an individual char */
                    BaseX, BaseY,   /* Start of baseline */
                    Rotation;       /* Angle of text (in degrees) */
        USHORT      NumChars;
        char        TextChars[NumChars];
    };

The text string is in the character array, TextChars[].  The ID of the
font used to render the text is WhichFont.  The font's ID is set in a
FONS chunk.  The starting point of the baseline of the text is (BaseX,
BaseY).  This is the point around which the text is rotated.  If the
Rotation field is zero (degrees), the text's baseline will originate
at (BaseX, BaseY) and move to the right.  CharW and CharH are used to
scale the text after rotation.  CharW is the average character width
and CharH is the average character height.  The CharW/H fields are
comparable to an X and Y font size.