//TEXTCENTER, left, top, right, bottom, text
TEXTCENTER outputs a line of text, positioning it in the center of the specified rectangular coordinates.
Parameters
Left, top, right, bottom
Specify the respective sides of the bounding rectangle, in the current mapping units. Note that if the rectangle has no height (bottom >= top) then the text is vertically positioned based on the top parameter and the current SETTEXTALIGN setting. Other, it is not affected by SETTEXTALIGN.
text
A string of text to output, up to a maximum of 512 characters (after expansion of any variables). TEXTCENTER does not require quoting of the text argument if it contains commas, although quoting is allowed and recommended.
See TEXTRECTANGLE for a more powerful variation of outputting text within a rectangular area.