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Re: MF hackery (arrow kit) + CM design questions

> You are right about the sources (mainly cmsy, msam and msbm, IIRC)
> Could you explain the `latest' design principles and their diffence
> to `old CM' ?

It all revolves around Knuth's changes to the CM sources made in 1992.
The basic change was that arrowheads were made both heaver and bigger.
Making them a little heavier was achieved by using |rule_thickness|
instead of |bar|.  Making them bigger was achieved by moving the z9
control point and the z3, z4 end points a little further back from 
the tip of the arrows.  It appears that the triple arrowheads (from 
AMS fonts) were still based on the old design, so it was drawn using 
the |bar| parameter, but everything should be consistent now.

[ regarding CM square brackets and floors/ceilings ]

> What would a consistent setting be ? 
> 6u for the basic size floor/ceiling, I guess. Perhaps we will have
> to create two sets of virtual fonts, one set with the old metrics
> and one with improved metrics. On the other hand, perhaps we can
> drop the whole idea of metric compatibility, as long as something
> like my oldmath.sty is available. The old cm math fonts will always be
> available... 

I supspect that the reasons for the inconsistencies in the original
values is that the square brackets were designed for use in text
(taken from cmr), while floor/ceiling brackets (taken from cmsy) 
were designed for use in math.

I always had the impression that the side-bearings for CM square
brackets were too small, so I would rather tend to make the square
brackets as wide as the floor/ceiling brackets instead of the 
other way round.  OTOH, I don't see the reason why the basic size
floor/ceiling brackets should be any wider than the big sizes.

Maybe the best approach is to create a few sets of different width 
and experiment with what looks best.  Personally, I found that 
I often used something like \Bigl[\, to insert additional space 
while I never did that for \Bigl(.  As for floors and ceilings, 
I have no experience as I never had any need for them in physics.

Cheers, Ulrik.