Re: Fixes heights and pure heights of stems. (issue 4898044)

[Keith OHara]

On Mon, 26 Mar 2012 23:14:15 -0700, Mike Solomon <address@hidden> wrote:

> >  The code in lily/note-collision.cc:219 needs an update to adjust the
> > stem beginning (issue 2441).  I tried but I can't find the "pure
> > callback for stem beginnings".
>
> ly:stem::pure-calc-stem-begin-position

Okay, it is actually the not-pure version that causes trouble.

When internal_calc_stem_begin_position (Grob *me, bool calc_beam)
is called to actually print the stems, calc_beam is true, and
+  if (beam && calc_beam)
+    {
+      (void) beam->get_property ("quantized-positions");
+      return me->extent (me, Y_AXIS)[-get_grob_direction (me)] * ss * 2;
+    }
returns an answer that does not include the results of
  Real y_attach = Note_head::stem_attachment_coordinate (head, Y_AXIS);

It seems that the /begin/ positions, the positions of the stem-ends attached to 
the note heads, should be calculated the old way whether the beam placement has 
been determined or not, so I'm inclined to remove if() above, removing the need 
for a pure_* version of calc-stem-begin-position.

> Lemme know if I can be of help w/ fixing this!

I'd rather you did.

-Keith