Re: Vertical centering inconsistency

[<HBB...@t-...>]

m sutton wrote:

> I did some investigating.  I found that the X11, CGM and Postscript
> enhanced will do vertical centering.  PNG (gd), Postscript, and EMF
> do not do vertical centering.

At least by intention, that constitutes a bug in the latter three 
drivers.  The wording is not as clear as it could be, but let's see what 
the applicable documentation in term/README says this about put_text():

_put_text(x,y,str)  Called to display text at the (x,y) position,
while in graphics mode.   The text should be vertically (with respect
to the text) justified about (x,y).  The text is rotated according
to _text_angle and then horizontally (with respect to the text)
justified according to _justify_text.

Now admittedly the term "justified about" is not excessively clear, but 
I always understood this to mean "centered".  Quite a number of routines 
in the gnuplot core also assume that's what it means.  If you go looking 
for term->v_char / 2 a bit, you'll see what I mean.

For a simple, test, look at the output from

	set label 1 "<--- here" at 1,1
	plot x

The head of this "text arrow" is supposed to be exactly on the diagonal 
plotted line.