Fret diagram fixes (issue4176056)

[nicolas . sceaux]

Reviewers: carl.d.sorensen_gmail.com,

Message:
Hi,

Here is a patch for fret diagrams, but as I have very little knowledge
of them I may well be wrong on some points.

First, it fixes sizing issues, when the size property is overridden: the
xo signs became too big, and too far from the first fret. It seems that
there was a unnecessary "* size".

Then, it adds the possibility to use letters for fingers. On the book
I'm reading, "P" is used for the thumb ("pouce" in French).

A new feature is also to invert a dot color, on a per-dot basis. Also on
the book I'm referring to, this is used to show where the fundamental
note is on a chord.

Finally, the patch adds a way to customize the first fret label.
There is also a modification of the first fret label position, but maybe
this is a mistake. Is the label supposed to be vertically centered with
the fret line? or the bottom of the label should be aligned with the
fret line? In the former case, I should cancel the modification.

I'm posting pics in a follow up of this post, to illustrate these
modifications.

Nicolas


Description:
Fret diagram fixes

- fix padding and size of mute/open signs when size is overridden
- fix first fret label position (maybe this was not a problem?)
- allow non numeric fingers (e.g. for thumb)
- allow fully customizable first fret label
- allow per-finger dot color change

Please review this at http://codereview.appspot.com/4176056/

Affected files:
  scm/define-grob-properties.scm
  scm/fret-diagrams.scm


Index: scm/define-grob-properties.scm
diff --git a/scm/define-grob-properties.scm b/scm/define-grob-properties.scm
index  
168a4f43d8a3432621128d76f0e48b0c90d3bd05..d010617f01cd0be9fcd37948156512173d31b735  
100644
--- a/scm/define-grob-properties.scm
+++ b/scm/define-grob-properties.scm
@@ -333,6 +333,10 @@ Default @code{none} for markup fret diagrams,  
@code{below-string} for
 @item
 @code{fret-count} -- The number of frets.  address@hidden
 @item
address@hidden -- The format string to be used label
+the lowest fret number, when @code{number-type} equals to
address@hidden  address@hidden"~a\".
address@hidden
 @code{fret-label-font-mag} -- The magnification of the font used to
 label the lowest fret number.  address@hidden
 @item
@@ -348,7 +352,9 @@ address@hidden
 string.  Default @code{\"x\"}.
 @item
 @code{number-type} -- Type of numbers to use in fret label.  Choices
-include @code{roman-lower}, @code{roman-upper}, and @code{arabic}.
+include @code{roman-lower}, @code{roman-upper}, @code{arabic} and
address@hidden  In the later case, the format string is supplied by
+the @code{fret-label-custom-format} property.
 Default @code{roman-lower}.
 @item
 @code{open-string} -- Character string to be used to indicate open
Index: scm/fret-diagrams.scm
diff --git a/scm/fret-diagrams.scm b/scm/fret-diagrams.scm
index  
558c11ebf679a8067617fcd90c93a0546ed2a7df..7b3d312c25b4b42b27206be9b11e47f9f3d5b600  
100644
--- a/scm/fret-diagrams.scm
+++ b/scm/fret-diagrams.scm
@@ -72,10 +72,20 @@ to end-point."
   (if (null? dot-list)
       '()
       (let ((this-list (car dot-list)))
-        (cons* (list (car this-list) (- (second this-list) base-fret)
-                     (if (null? (cddr this-list))
-                         '()
-                         (third this-list)))
+        (cons* (list
+                ;; string
+                (car this-list)
+                ;; fret
+                (- (second this-list) base-fret)
+                ;; finger
+                (if (null? (cddr this-list))
+                    '()
+                    (third this-list))
+                ;; color modifier
+                (if (or (null? (cddr this-list))
+                        (null? (cdddr this-list)))
+                    '()
+                    (fourth this-list)))
                (subtract-base-fret base-fret (cdr dot-list))))))

 (define (drop-paren item-list)
@@ -275,8 +285,7 @@ with magnification @var{mag} of the string @var{text}."
          (thickness-factor (assoc-get 'string-thickness-factor details 0))
          (alignment
            (chain-assoc-get 'align-dir props -0.4)) ; needed only here
-         (xo-padding
-           (* size (assoc-get 'xo-padding details 0.2))) ; needed only here
+         (xo-padding (assoc-get 'xo-padding details 0.2)) ; needed only  
here
          (parameters (fret-parse-marking-list marking-list my-fret-count))
          (capo-fret (assoc-get 'capo-fret parameters 0))
          (dot-list (assoc-get 'dot-list parameters))
@@ -529,9 +538,9 @@ fret-diagram overall parameters."
      (define (draw-dots dot-list)
        "Make dots for fret diagram."

-       (let* ( (scale-dot-radius (* size dot-radius))
+       (let* ((scale-dot-radius (* size dot-radius))
               (scale-dot-thick (* size th))
-              (dot-color (assoc-get 'dot-color details 'black))
+              (default-dot-color (assoc-get 'dot-color details 'black))
               (finger-label-padding 0.3)
               (dot-label-font-mag
                 (* scale-dot-radius
@@ -554,18 +563,23 @@ fret-diagram overall parameters."
                 (stencil-coordinates fret-coordinate string-coordinate))
               (extent (cons (- scale-dot-radius) scale-dot-radius))
               (finger (caddr mypair))
-              (finger (if (number? finger) (number->string finger) finger))
+              (finger (fancy-format #f "~a" finger))
+              (inverted-color (eq? 'inverted (cadddr mypair)))
+              (dot-color (if (or (and (eq? default-dot-color 'black)  
inverted-color)
+                                 (and (eq? default-dot-color 'white) (not  
inverted-color)))
+                             'white
+                             'black))
               (dot-stencil (if (eq? dot-color 'white)
-                             (ly:stencil-add
-                               (make-circle-stencil
+                               (ly:stencil-add
+                                (make-circle-stencil
                                  scale-dot-radius scale-dot-thick #t)
-                               (ly:stencil-in-color
+                                (ly:stencil-in-color
                                  (make-circle-stencil
-                                   (- scale-dot-radius (* 0.5  
scale-dot-thick))
-                                   0  #t)
+                                  (- scale-dot-radius (* 0.5  
scale-dot-thick))
+                                  0  #t)
                                  1 1 1))
-                             (make-circle-stencil
-                               scale-dot-radius scale-dot-thick #t)))
+                               (make-circle-stencil
+                                scale-dot-radius scale-dot-thick #t)))
               (positioned-dot
                 (ly:stencil-translate dot-stencil dot-coordinates))
               (labeled-dot-stencil
@@ -641,12 +655,11 @@ fret-diagram overall parameters."
        "Put open and mute string indications on diagram, as contained in
 @var{xo-list}."
        (let* ((xo-font-mag
-                (* size (assoc-get
-                          'xo-font-magnification details
+               (assoc-get 'xo-font-magnification details
                           (cond ((or (eq? orientation 'landscape)
                                      (eq? orientation 'opposing-landscape))
                                  0.4)
-                                (else 0.4)))))
+                                (else 0.4))))
               (mypair (car xo-list))
               (restlist (cdr xo-list))
               (glyph-string (if (eq? (car mypair) 'mute)
@@ -709,6 +722,11 @@ at @var{fret}."
                       (fancy-format #f "address@hidden" base-fret))
                      ((equal? 'arabic number-type)
                       (fancy-format #f "~d" base-fret))
+                     ((equal? 'custom number-type)
+                      (fancy-format #f
+                                    (assoc-get 'fret-label-custom-format
+                                               details "~a")
+                                    base-fret))
                      (else (fancy-format #f "~(address@hidden)" base-fret))))
                  (label-stencil
                    (centered-stencil
@@ -723,7 +741,7 @@ at @var{fret}."
             (ly:stencil-translate
               label-stencil
               (stencil-coordinates
-                (1+ (* size label-vertical-offset))
+                (* size (+ 0.5 label-vertical-offset))
                 (if (eq? label-dir LEFT)
                   (- label-outside-diagram)
                   (+ (* size (1- string-count)) label-outside-diagram))))))
@@ -966,12 +984,15 @@ Place a capo indicator (a large solid bar) across the  
entire fretboard
 at fret location @var{fret-number}.  Also, set fret @var{fret-number}
 to be the lowest fret on the fret diagram.

address@hidden (place-fret @var{string-number} @var{fret-number} 
@var{finger-value})
address@hidden (place-fret @var{string-number} @var{fret-number}  
address@hidden address@hidden)
 Place a fret playing indication on string @var{string-number} at fret
address@hidden with an optional fingering label @var{finger-value}.
address@hidden with an optional fingering label @var{finger-value},
+and an optional color modifier @var{color-modifier}.
 By default, the fret playing indicator is a solid dot.  This can be
-changed by setting the value of the variable @var{dot-color}.  If the
address@hidden part of the @code{place-fret} element is present,
+globally changed by setting the value of the variable @var{dot-color}.
+Setting @var{color-modifier} to @code{inverted} inverts the dot color
+for a specific fingering.
+If the @var{finger} part of the @code{place-fret} element is present,
 @var{finger-value} will be displayed according to the setting of the
 variable @var{finger-code}.  There is no limit to the number of fret
 indications per string.