a couple textspanner problems

[scott snyder]

hi -

I had a few problems trying to set ottavas with recent lilypond versions.
I'm using a linux/i86 system.

I started out using lily 1.3.119, compiled with gcc 2.95.2.
Here's the test case i used:

--------------------------------------------------------------------------
\score{
    \notes\relative c'''{
        \property Voice.TextSpanner \override #'type = #'dashed-line
        \property Voice.TextSpanner \override #'edge-height = #'(0 . 1.5)
        \property Voice.TextSpanner \override #'edge-text = #'("8va " . "")
        \property Staff.centralCPosition = #-13

        a16\spanrequest \start "text" b c a a b c a a b c a a b c a\spanrequest 
\stop "text"
        a b c a a b c a a b c a a b c a
    }
}
--------------------------------------------------------------------------

What i was seeing was that the entire ottava bar was shifted to the right
of where it should be, by about the space of 3-4 note heads.
After upgrading to lily 1.3.121 and the redhat gcc 2.96, though,
the symptoms went away.  However, i had already tracked down the problem,
and the underlying cause is still there --- it was a read of an
uninitialized variable in text-spanner.cc.  Here's a patch to fix it:

--- text-spanner.cc-orig        Mon Jan  8 01:03:05 2001
+++ text-spanner.cc     Sat Jan  6 02:36:49 2001
@@ -49,6 +49,7 @@
     {
       Item *b = spanner->get_bound (d);
       broken[d] = b->break_status_dir () != CENTER;
+      extra_off[d] = 0;
 
       if (!broken [d])
        {


Second, when i run this testcase, i get the annoying warnings
(this is reproducable with lily 1.3.121):

Interpreting music...
ottava.ly:8:37: warning: already have a text spanner:
        a16\spanrequest \start "text"
                                      b c a a b c a a b c a a b c a\spanrequest 
\stop "text"

ottava.ly:8:37: warning: already have a text spanner:
        a16\spanrequest \start "text"
                                      b c a a b c a a b c a a b c a\spanrequest 
\stop "text"

ottava.ly:8:92: warning: can't find start of text spanner:
        a16\spanrequest \start "text" b c a a b c a a b c a a b c a\spanrequest 
\stop "text"
                                                                                
            

ottava.ly:8:92: warning: can't find start of text spanner:
        a16\spanrequest \start "text" b c a a b c a a b c a a b c a\spanrequest 
\stop "text"


It looked to me like the problem was that Text_spanner_engraver::create_grobs
wasn't clearing req_drul_ after processing it.  The following change
seems to fix the problem:

--- text-spanner-engraver.cc-orig       Mon Jan  8 01:55:33 2001
+++ text-spanner-engraver.cc    Sat Jan  6 02:39:16 2001
@@ -103,6 +103,7 @@
          finished_ = span_;
          span_ = 0;
          current_req_ = 0;
+          req_drul_[STOP] = 0;
        }
     }
 
@@ -127,6 +128,7 @@
          Grob *e = unsmob_grob (get_property ("currentMusicalColumn"));
          span_->set_bound (LEFT, e);
          announce_grob (span_, req_drul_[START]);
+          req_drul_[START] = 0;
        }
     }
 }



Also, while playing around with this, i found what looks like a typo in
translator-group.cc:

--- translator-group.cc-orig    Fri Jan  5 01:05:33 2001
+++ translator-group.cc Fri Jan  5 01:05:55 2001
@@ -459,7 +459,7 @@
 add_trans_scm_funcs ()
 {
   scm_make_gsubr ("ly-get-trans-property", 2, 0, 0, 
(Scheme_function_unknown)ly_get_trans_property);
-  scm_make_gsubr ("ly-get-trans-property", 3, 0, 0, 
(Scheme_function_unknown)ly_get_trans_property);
+  scm_make_gsubr ("ly-set-trans-property", 3, 0, 0, 
(Scheme_function_unknown)ly_set_trans_property);
 }
 
 ADD_SCM_INIT_FUNC(trans_scm, add_trans_scm_funcs);


Finally, a question: how does one retrieve the value of a property
like Staff.centralCPosition from scheme?  I set up abbreviations like

startottava = \notes {
  \property Voice.TextSpanner \set #'type = #'dashed-line
  \property Voice.TextSpanner \set #'edge-height = #'(0 . 1.5)
  \property Voice.TextSpanner \set #'edge-text = #'("8va " . "")
  \property Staff.centralCPosition = #-13
}

endottava = \notes {
  \property Staff.centralCPosition = #-6
}

but i wanted to make them work correctly regardless of what the current
clef is.  (I tried to put the spanrequests inside these constructions too,
but doing that i wasn't able to get the range of spanned notes consistent
with the range where the staff C position had been changed.)

thanks,
sss