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	I am trying to impliment tabs in a TextEdit window, similar
	to the Consulair's Edit program.  I don't know exactly how
	to do it, but I have tried using SetStdProcs to change
	the standard text measuring and text drawing routines for
	that window.  The following is my section of code (in MegaMax C):

	#define	TABSTOP	100	/* In units of pixels, not char widths */

	mystdtxmeas	(info, denom, numer, textbuf, bytecount)
				/* Parameters are normally reversed in
				   MegaMax C */
		reg	char	*textbuf;
		point	*numer, *denom;
		finfo	*finfo;
		reg	int	bytecount;
		{
		reg	int	size;
		reg	char	*s;

		size = theport->pnloc.a.h;	/* Actually, the pen
						   location isn't always
						   right, but I have a way
						   to make it so. */
		s = textbuf;			/* We start at beginning
						   of buffer */

		/* Scan each character in buffer for tabs */
		while	(bytecount--)
			{
			/* If tab occurs, bring to next tabstop */
			if	(*textbuf++ == '\t')
				{
				/* <<< */
				size += stdtxmeas(info, denom, numer,
					s, textbuf-s-1) + TABSTOP+1;
				size -= size % TABSTOP + 1;
				s = textbuf;
				/* >>> */
				}
			}
		size += stdtxmeas(info, denom, numer, s, textbuf-s)
			- theport->pnloc.a.h;
		return	(size);		/* Returning is really a little
					   more involved in MegaMax.
					   This isn't the problem. */
		}
	
	Of course, then I make the qdprocs pointer txmeas in theport
	point to this procedure.  This works great, EXCEPT, that it
	is very slow.  I looked at the code, and it looked very
	optimal.  I even hand-optimized it, and it is STILL slow.
	To test the speed of the division, I replace the lines between
	<<< and >>> with:

				size += stdtxmeas(info, denom, numer,
					s, textbuf-s);

	This simulates the normal stdtxmeas, but without tabstops,
	and it is STILL slow.  Then, I replaced the "if" statement
	with if(0) and it became fast.  It told me that calling
	stdtxmeas several times slows it down considerable, even
	though I am still measuring the size of each character
	only once.

	What can I do, then, to speed up this whole operation?
	Obviously, Consulair did it, so it must be possible.
	Maybe there is a better way to begin with?

	Incidently, I disassembled some of the code in ROM's
	stdtxmeas, and it looks like there is a lot of setting up
	of things before any measuring of text begins.  I think
	this is what is slowing everything down -- my way causes
	this initialization to occur repetitively.  Is there perhaps
	a way to bypass the initializing routines?

	Incidently, I have a fast working version that only works
	for fixed fonts.  This was easy because I don't have
	to call stdtxmeas at all.  But I need to do all this
	with proportional fonts as well.

	Thanks very much for any help anyone can give.


			Victor Romano