Doc: MG: add incomplete dominant seventh chord (2749)

diff --git a/Documentation/music-glossary.tely b/Documentation/music-glossary.tely
index a57dffbe63beb09c0693e1e0675754c9f6930832..306d0504d80c4d837d1f3bf39c4b0eb1969906dd 100644 (file)
--- a/Documentation/music-glossary.tely
+++ b/Documentation/music-glossary.tely
@@ -248,6 +248,7 @@ Languages in this order.
 * homophony::
 * hook::
 * hymn meter::
+* incomplete dominant seventh chord::
 * interval::
 * inversion::
 * inverted interval::
@@ -3876,10 +3877,29 @@ functionally different chords: tonic (T, the chord on the first note of the
 scale), subdominant (S, the chord on the fourth note), and dominant (D, the
 chord on the fifth note).  Others are considered to be variants of the base
 chords.
-
-TODO: what does the @q{p} mean in Sp, Dp, Tp?
+A few examples among many others are the tonic, subdominant or dominant of
+the parallel minor scale, or the incomplete dominant seventh chord.
 
 @lilypond[quote,notime,relative=2,line-width=13.0\cm]
+#(define-markup-command (diagonal-stroke layout props arg)
+  (markup?)
+  #:category font
+  #:properties ((font-size 0) (thickness 1.5) (extension 0.07))
+  (let*
+   ((thick (* (magstep font-size)
+      (ly:output-def-lookup layout 'line-thickness)))
+    (underline-thick (* thickness thick))
+    (markup (interpret-markup layout props arg))
+    (x1 (car (ly:stencil-extent markup X)))
+    (x2 (cdr (ly:stencil-extent markup X)))
+    (y1 (car (ly:stencil-extent markup Y)))
+    (y2 (cdr (ly:stencil-extent markup Y)))
+    (dx (* extension (- x2 x1)))
+    (dy (* extension (- y2 y1)))
+    (line (make-line-stencil underline-thick
+      (- x1 dx) (- y1 dy)
+      (+ x2 dx) (+ y2 dy))))
+   (ly:stencil-add markup line)))
 <<
   {
     <g e c>1 <a f d> <b g e>
@@ -3887,13 +3907,14 @@ TODO: what does the @q{p} mean in Sp, Dp, Tp?
   }
   \lyrics {
     T Sp Dp S D Tp
-    \markup { D \translate #'(-2 . 0) | }
+    \markup { \concat { \diagonal-stroke D \super "7" } }
   }
 >>
 @end lilypond
 
 @seealso
-No cross-references.
+@ref{dominant}, @ref{incomplete dominant seventh chord},
+@ref{subdominant}, @ref{tonic}.
 
 
 @node G
@@ -4335,6 +4356,25 @@ easier reading, a hymn with a meter of 87.87.87.87 is usually written
 No cross-references.
 
 
+@node incomplete dominant seventh chord
+@section incomplete dominant seventh chord
+
+ES: ?,
+I: ?,
+F: ?,
+D: verkürzter Dominantseptakkord,
+NL: ?,
+DK: ?,
+S: ?,
+FI: ?.
+
+A dominant seventh chord where the root tone is removed.
+The remaining three tones build a diminished triad.
+
+@seealso
+@ref{chord}, @ref{dominant seventh chord}, @ref{functional harmony}.
+
+
 @node interval
 @section interval