;;;; fret-diagrams.scm -- ;;;; ;;;; source file of the GNU LilyPond music typesetter ;;;; ;;;; (c) 2004--2006 Carl D. Sorensen (define (fret-parse-marking-list marking-list fret-count) (let* ((fret-range (list 1 fret-count)) (barre-list '()) (dot-list '()) (xo-list '()) (output-alist '())) (let parse-item ((mylist marking-list)) (if (not (null? mylist)) (let* ((my-item (car mylist)) (my-code (car my-item))) (cond ((or (eq? my-code 'open)(eq? my-code 'mute)) (set! xo-list (cons* my-item xo-list))) ((eq? my-code 'barre) (set! barre-list (cons* (cdr my-item) barre-list))) ((eq? my-code 'place-fret) (set! dot-list (cons* (cdr my-item) dot-list)))) (parse-item (cdr mylist))))) ; calculate fret-range (let ((maxfret 0) (minfret 99)) (let updatemax ((fret-list dot-list)) (if (null? fret-list) '() (let ((fretval (second (car fret-list)))) (if (> fretval maxfret) (set! maxfret fretval)) (if (< fretval minfret) (set! minfret fretval)) (updatemax (cdr fret-list))))) (if (> maxfret fret-count) (set! fret-range (list minfret (let ((upfret (- (+ minfret fret-count) 1))) (if (> maxfret upfret) maxfret upfret))))) ; subtract fret from dots (set! dot-list (subtract-base-fret (- (car fret-range) 1) dot-list))) (acons 'fret-range fret-range (acons 'barre-list barre-list (acons 'dot-list dot-list (acons 'xo-list xo-list '())))))) (define (subtract-base-fret base-fret dot-list) "Subtract @var{base-fret} from every fret in @var{dot-list}" (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))) (subtract-base-fret base-fret (cdr dot-list)))))) (define (sans-serif-stencil layout props mag text) "create a stencil in sans-serif font based on @var{layout} and @var{props} with magnification @varr{mag} of the string @var{text}." (let* ((my-props (prepend-alist-chain 'font-size (stepmag mag) (prepend-alist-chain 'font-family 'sans props)))) (interpret-markup layout my-props text))) (define (draw-strings string-count fret-range th size) "Draw the strings (vertical lines) for a fret diagram with @var{string-count} strings and frets as indicated in @var{fret-range}. Line thickness is given by @var{th}, fret & string spacing by @var{size}. " (let* ((fret-count (+ (- (cadr fret-range) (car fret-range)) 1)) (sl (* (+ fret-count 1) size)) (sth (* size th)) (half-thickness (* sth 0.5)) (gap (- size sth)) (string-stencil (ly:make-stencil (list 'draw-line sth 0 0 0 sl) (cons (- half-thickness) half-thickness) (cons (- half-thickness) (+ sl half-thickness))))) (if (= string-count 1) string-stencil (ly:stencil-combine-at-edge (draw-strings (- string-count 1) fret-range th size) X RIGHT string-stencil gap 0)))) (define (draw-fret-lines fret-count string-count th size) "Draw @var{fret-count} frets (horizontal lines) for a fret diagram with @var{string-count} strings. Line thickness is given by @var{th}, fret & string spacing by @var{size}. " (let* ((fret-length (* (- string-count 1) size)) (sth (* size th)) (half-thickness (* sth 0.5)) (gap (- size sth)) (fret-line (ly:make-stencil (list 'draw-line sth half-thickness size (- fret-length half-thickness) size) (cons 0 fret-length) (cons (- size half-thickness) (+ size half-thickness))))) (if (= fret-count 1) fret-line (ly:stencil-combine-at-edge fret-line Y UP (draw-fret-lines (- fret-count 1) string-count th size) gap 0)))) (define (draw-thick-top-fret props string-count th size) "Draw a thick top fret for a fret diagram whose base fret is not 1." (let* ((sth (* th size)) ; (top-fret-thick (* sth (chain-assoc-get 'top-fret-thickness props 3.0))) (top-fret-thick (* sth 3.0)) ; (top-half-thick (* top-fret-thick 0.5)) (half-thick (* sth 0.5)) (x1 half-thick) (x2 (+ half-thick (* size (- string-count 1)))) (y1 (- half-thick)) (y2 (+ top-fret-thick half-thick)) (x-extent (cons (- x1) x2)) (y-extent (cons 0 y2))) (ly:make-stencil (list 'round-filled-box x1 x2 y1 y2 sth) x-extent y-extent))) (define (draw-frets layout props fret-range string-count th size) "Draw the frets (horizontal lines) for a fret diagram with @var{string-count} strings and frets as indicated in @var{fret-range}. Line thickness is given by @var{th}, fret & string spacing by @var{size}. " (let* ((fret-count (+ (- (cadr fret-range) (car fret-range)) 1)) (fret-length (* (- string-count 1) size)) (half-thickness (* th 0.5)) (base-fret (car fret-range))) (ly:stencil-combine-at-edge (draw-fret-lines fret-count string-count th size) Y UP (if (= base-fret 1) (draw-thick-top-fret props string-count th size) (draw-fret-lines 1 string-count th size)) (- size th) 0))) (define (draw-dots layout props string-count fret-range size finger-code dot-position dot-radius dot-thickness dot-list) "Make dots for fret diagram." (let* ((scale-dot-radius (* size dot-radius)) (scale-dot-thick (* size dot-thickness)) (dot-color (chain-assoc-get 'dot-color props 'black)) ; (finger-xoffset (chain-assoc-get 'finger-xoffset props -0.25)) ; (finger-yoffset (chain-assoc-get 'finger-yoffset props (- size))) (finger-xoffset -0.25) (finger-yoffset (- (* size 0.5))) ; (dot-label-font-mag (* scale-dot-radius (chain-assoc-get 'dot-label-font-mag props 1.0))) (dot-label-font-mag scale-dot-radius) ; (string-label-font-mag (* size (chain-assoc-get 'label-font-mag props 0.7))) (string-label-font-mag (* size 0.6)) (fret-count (+ (- (cadr fret-range) (car fret-range) 1))) (mypair (car dot-list)) (restlist (cdr dot-list)) (xpos (* size (- string-count (car mypair)))) ;TODO -- figure out what 4 is and get rid of it ;UGH -- 4? (ypos (* size (+ 4 (- fret-count (cadr mypair) dot-position )))) (extent (cons (- scale-dot-radius) scale-dot-radius)) (finger (caddr mypair)) (finger (if (number? finger) (number->string finger) finger)) (dotstencil (if (eq? dot-color 'white) (ly:stencil-add (make-circle-stencil scale-dot-radius scale-dot-thick #t) (ly:stencil-in-color (make-circle-stencil (- scale-dot-radius (* 0.5 scale-dot-thick)) 0 #t) 1 1 1)) (make-circle-stencil scale-dot-radius scale-dot-thick #t))) (positioned-dot (begin ;(display dotstencil) (ly:stencil-translate-axis (ly:stencil-translate-axis dotstencil xpos X) ypos Y))) (labeled-dot-stencil (if (or (eq? finger '())(eq? finger-code 'none)) positioned-dot (if (eq? finger-code 'in-dot) (let* ((finger-label (centered-stencil (sans-serif-stencil layout props dot-label-font-mag finger)))) (ly:stencil-translate-axis (ly:stencil-translate-axis (ly:stencil-add dotstencil (if (eq? dot-color 'white) finger-label (ly:stencil-in-color finger-label 1 1 1))) xpos X) ypos Y)) (if (eq? finger-code 'below-string) (ly:stencil-add positioned-dot (ly:stencil-translate-axis (ly:stencil-translate-axis (centered-stencil (sans-serif-stencil layout props string-label-font-mag finger)) xpos X) (* size finger-yoffset) Y)) ;unknown finger-code positioned-dot))))) (if (null? restlist) labeled-dot-stencil (ly:stencil-add (draw-dots layout props string-count fret-range size finger-code dot-position dot-radius dot-thickness restlist) labeled-dot-stencil)))) (define (draw-xo layout props string-count fret-range size xo-list) "Put open and mute string indications on diagram, as contained in @var{xo-list}." (let* ((fret-count (+ (- (cadr fret-range) (car fret-range) 1))) ; (xo-font-mag (* size (chain-assoc-get 'xo-font-magnification props 0.5))) (xo-font-mag (* size 0.5)) ; (xo-horizontal-offset (* size (chain-assoc-get 'xo-horizontal-offset props -0.35))) (xo-horizontal-offset (* size -0.35)) (mypair (car xo-list)) (restlist (cdr xo-list)) (glyph-string (if (eq? (car mypair) 'mute) "X" "O")) (xpos (+ (* (- string-count (cadr mypair)) size) xo-horizontal-offset )) (glyph-stencil (ly:stencil-translate-axis (sans-serif-stencil layout props (* size xo-font-mag) glyph-string) xpos X))) (if (null? restlist) glyph-stencil (ly:stencil-add (draw-xo layout props string-count fret-range size restlist) glyph-stencil)))) (define (make-bezier-sandwich-list left right bottom height thickness) " Make the argument list for a horizontal bezier sandwich from @var{left} to @var{right} with a bottom at @var{bottom}, a height of @var{height}, and a thickness of @var{thickness}." (let* ((width (+ (- right left) 1)) (x1 (+ (* width thickness) left)) (x2 (- right (* width thickness))) (bottom-control-point-height (+ bottom (- height thickness))) (top-control-point-height (+ bottom height))) ; order of points is: left cp low, right cp low, right end low, left end low ; right cp high, left cp high, left end high, right end high. (list (cons x1 bottom-control-point-height) (cons x2 bottom-control-point-height) (cons right bottom) (cons left bottom) (cons x2 top-control-point-height) (cons x1 top-control-point-height) (cons left bottom) (cons right bottom)))) (define (draw-barre layout props string-count fret-range size finger-code dot-position dot-radius barre-list) "Create barre indications for a fret diagram" (if (not (null? barre-list)) (let* ((string1 (caar barre-list)) (string2 (cadar barre-list)) (fret (caddar barre-list)) (barre-type (chain-assoc-get 'barre-type props 'curved)) (scale-dot-radius (* size dot-radius)) (barre-vertical-offset (chain-assoc-get 'barre-vertical-offset props 0.5)) ;; 2 is 1 for empty fret at bottom of figure + 1 for interval (top-fret - fret + 1) -- not an arbitrary constant (dot-center-y (* size (- (+ 2 (- (cadr fret-range) fret)) dot-position))) (bottom (+ dot-center-y (* barre-vertical-offset scale-dot-radius))) (left (* size (- string-count string1))) (right (* size (- string-count string2))) ;; (bezier-thick (chain-assoc-get 'bezier-thickness props 0.1)) (bezier-thick 0.1) ;; (bezier-height (chain-assoc-get 'bezier-height props 0.5)) (bezier-height 0.5) (bezier-list (make-bezier-sandwich-list left right bottom (* size bezier-height) (* size bezier-thick))) (barre-stencil (if (eq? barre-type 'straight) (ly:make-stencil (list 'draw-line (* size dot-radius) left dot-center-y right dot-center-y) (cons left right) (cons (- dot-center-y scale-dot-radius) (+ dot-center-y scale-dot-radius))) (ly:make-stencil (list 'bezier-sandwich `(quote ,bezier-list) (* size bezier-thick)) (cons left right) (cons bottom (+ bottom (* size bezier-height))))))) (if (not (null? (cdr barre-list))) (ly:stencil-add barre-stencil (draw-barre layout props string-count fret-range size finger-code dot-position dot-radius (cdr barre-list))) barre-stencil )))) (define (stepmag mag) "Calculate the font step necessary to get a desired magnification" (* 6 (/ (log mag) (log 2)))) (define (label-fret layout props string-count fret-range size) "Label the base fret on a fret diagram" (let* ((base-fret (car fret-range)) ; (label-font-mag (chain-assoc-get 'label-font-mag props 0.7)) (label-font-mag 0.5) ; (label-vertical-offset (chain-assoc-get 'fret-label-vertical-offset props -0.2)) (label-vertical-offset -0.2) (number-type (chain-assoc-get 'number-type props 'roman-lower)) (fret-count (+ (- (cadr fret-range) (car fret-range)) 1)) (label-text (cond ((equal? number-type 'roman-lower) (format #f "~(~:@r~)" base-fret)) ((equal? number-type 'roman-upper) (format #f "~:@r" base-fret)) ((equal? 'arabic number-type) (format #f "~d" base-fret)) (else (format #f "~(~:@r~)" base-fret))))) (ly:stencil-translate-axis (sans-serif-stencil layout props (* size label-font-mag) label-text) (* size (+ fret-count label-vertical-offset)) Y))) (define-markup-command (fret-diagram-verbose layout props marking-list) (list?) "Make a fret diagram containing the symbols indicated in @var{marking-list} For example, @example \\markup \\fret-diagram #'((mute 6) (mute 5) (open 4) (place-fret 3 2) (place-fret 2 3) (place-fret 1 2)) @end example will produce a standard D chord diagram without fingering indications. Possible elements in @var{marking-list}: @table @asis @item (mute string-number) Place a small 'x' at the top of string @var{string-number} @item (open string-number) Place a small 'o' at the top of string @var{string-number} @item (barre start-string end-string fret-number) Place a barre indicator (much like a tie) from string @var{start-string}to string @var{end-string} at fret @var{fret-number} @item (place-fret string-number fret-number finger-value) Place a fret playing indication on string @var{string-number} at fret @var{fret-number} with an optional fingering label @var{finger-value}. 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 @var{finger} part of the 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. @end table " (make-fret-diagram layout props marking-list)) (define (make-fret-diagram layout props marking-list) " Make a fret diagram markup" (let* ( ; note: here we get items from props that are needed in this routine, or that are needed in more than one ; of the procedures called from this routine. If they're only used in one of the sub-procedure, they're ; obtained in that procedure (size (chain-assoc-get 'size props 1.0)) ; needed for everything ;TODO -- get string-count directly from length of stringTunings; requires FretDiagram engraver, which is not yet available ;TODO -- adjust padding for fret label? it appears to be too close to dots (string-count (chain-assoc-get 'string-count props 6)) ; needed for everything (fret-count (chain-assoc-get 'fret-count props 4)) ; needed for everything (finger-code (chain-assoc-get 'finger-code props 'none)) ; needed for both draw-dots and draw-barre (default-dot-radius (if (eq? finger-code 'in-dot) 0.425 0.25)) ; bigger dots if labeled (default-dot-position (if (eq? finger-code 'in-dot) (- 0.95 default-dot-radius) 0.6)) ; move up to make room for bigger if labeled (dot-radius (chain-assoc-get 'dot-radius props default-dot-radius)) ; needed for both draw-dots and draw-barre (dot-position (chain-assoc-get 'dot-position props default-dot-position)) ; needed for both draw-dots and draw-barre (th (* (ly:output-def-lookup layout 'line-thickness) (chain-assoc-get 'thickness props 0.5))) ; needed for both draw-frets and draw-strings (alignment (chain-assoc-get 'align-dir props -0.4)) ; needed only here ; (xo-padding (* th (chain-assoc-get 'padding props 2))) ; needed only here (label-space (* 0.25 size)) (xo-padding (* th size 5)) (label-dir (chain-assoc-get 'label-dir props RIGHT)) (parameters (fret-parse-marking-list marking-list fret-count)) (dot-list (cdr (assoc 'dot-list parameters))) (xo-list (cdr (assoc 'xo-list parameters))) (fret-range (cdr (assoc 'fret-range parameters))) (barre-list (cdr (assoc 'barre-list parameters))) (fret-diagram-stencil (ly:stencil-add (draw-strings string-count fret-range th size) (draw-frets layout props fret-range string-count th size)))) (if (not (null? barre-list)) (set! fret-diagram-stencil (ly:stencil-add (draw-barre layout props string-count fret-range size finger-code dot-position dot-radius barre-list) fret-diagram-stencil))) (if (not (null? dot-list)) (set! fret-diagram-stencil (ly:stencil-add fret-diagram-stencil (draw-dots layout props string-count fret-range size finger-code dot-position dot-radius th dot-list)))) (if (not (null? xo-list)) (set! fret-diagram-stencil (ly:stencil-combine-at-edge fret-diagram-stencil Y UP (draw-xo layout props string-count fret-range size xo-list) xo-padding 0))) (if (> (car fret-range) 1) (set! fret-diagram-stencil (ly:stencil-combine-at-edge fret-diagram-stencil X label-dir (label-fret layout props string-count fret-range size) label-space 0))) (ly:stencil-aligned-to fret-diagram-stencil X alignment) )) (define-markup-command (fret-diagram layout props definition-string) (string?) " Example @example \\markup \\fret-diagram #\"s:0.75;6-x;5-x;4-o;3-2;2-3;1-2;\" @end example for fret spacing 3/4 of staff space, D chord diagram Syntax rules for @var{definition-string}: @itemize @minus @item Diagram items are separated by semicolons. @item Possible items: @itemize @bullet @item s:number -- set the fret spacing of the diagram (in staff spaces). Default 1 @item t:number -- set the line thickness (in staff spaces). Default 0.05 @item h:number -- set the height of the diagram in frets. Default 4 @item w:number -- set the width of the diagram in strings. Default 6 @item f:number -- set fingering label type (0 = none, 1 = in circle on string, 2 = below string) Default 0 @item d:number -- set radius of dot, in terms of fret spacing. Default 0.25 @item p:number -- set the position of the dot in the fret space. 0.5 is centered; 1 is on lower fret bar, 0 is on upper fret bar. Default 0.6 @item c:string1-string2-fret -- include a barre mark from string1 to string2 on fret @item string-fret -- place a dot on string at fret. If fret is o, string is identified as open. If fret is x, string is identified as muted. @item string-fret-fingering -- place a dot on string at fret, and label with fingering as defined by f: code. @end itemize @item Note: There is no limit to the number of fret indications per string. @end itemize " (let ((definition-list (fret-parse-definition-string props definition-string))) (make-fret-diagram layout (car definition-list) (cdr definition-list)))) (define (fret-parse-definition-string props definition-string) "parse a fret diagram string and return a pair containing: props, modified as necessary by the definition-string a fret-indication list with the appropriate values" (let* ((fret-count 4) (string-count 6) (fret-range (list 1 fret-count)) (barre-list '()) (dot-list '()) (xo-list '()) (output-list '()) (new-props '()) (items (string-split definition-string #\;))) (let parse-item ((myitems items)) (if (not (null? (cdr myitems))) (let ((test-string (car myitems))) (case (car (string->list (substring test-string 0 1))) ((#\s) (let ((size (get-numeric-from-key test-string))) (set! new-props (acons 'size size new-props)))) ((#\f) (let* ((finger-code (get-numeric-from-key test-string)) (finger-id (case finger-code ((0) 'none) ((1) 'in-dot) ((2) 'below-string)))) (set! new-props (acons 'finger-code finger-id new-props)))) ((#\c) (set! output-list (cons-fret (cons 'barre (numerify (string-split (substring test-string 2) #\-))) output-list))) ((#\h) (let ((fret-count (get-numeric-from-key test-string))) (set! new-props (acons 'fret-count fret-count new-props)))) ((#\w) (let ((string-count (get-numeric-from-key test-string))) (set! new-props (acons 'string-count string-count new-props)))) ((#\d) (let ((dot-size (get-numeric-from-key test-string))) (set! new-props (acons 'dot-radius dot-size new-props)))) ((#\p) (let ((dot-position (get-numeric-from-key test-string))) (set! new-props (acons 'dot-position dot-position new-props)))) (else (let ((this-list (string-split test-string #\-))) (if (string->number (cadr this-list)) (set! output-list (cons-fret (cons 'place-fret (numerify this-list)) output-list)) (if (equal? (cadr this-list) "x" ) (set! output-list (cons-fret (list 'mute (string->number (car this-list))) output-list)) (set! output-list (cons-fret (list 'open (string->number (car this-list))) output-list))))))) (parse-item (cdr myitems))))) (if (eq? new-props '()) `(,props . ,output-list) `(,(cons new-props props) . ,output-list)))) (define (cons-fret new-value old-list) " Put together a fret-list in the format desired by parse-string " (if (eq? old-list '()) (list new-value) (cons* new-value old-list))) (define (get-numeric-from-key keystring) "Get the numeric value from a key of the form k:val" (string->number (substring keystring 2 (string-length keystring)))) (define (numerify mylist) "Convert string values to numeric or character" (if (null? mylist) '() (let ((numeric-value (string->number (car mylist)))) (if numeric-value (cons* numeric-value (numerify (cdr mylist))) (cons* (car (string->list (car mylist))) (numerify (cdr mylist))))))) (define-markup-command (fret-diagram-terse layout props definition-string) (string?) "Make a fret diagram markup using terse string-based syntax. Example @example \\markup \\fret-diagram-terse #\"x;x;o;2;3;2;\" @end example for a D chord diagram. Syntax rules for @var{definition-string}: @itemize @bullet @item Strings are terminated by semicolons; the number of semicolons is the number of strings in the diagram. @item Mute strings are indicated by \"x\". @item Open strings are indicated by \"o\". @item A number indicates a fret indication at that fret. @item If there are multiple fret indicators desired on a string, they should be separated by spaces. @item Fingerings are given by following the fret number with a \"-\", followed by the finger indicator, e.g. 3-2 for playing the third fret with the second finger. @item Where a barre indicator is desired, follow the fret (or fingering) symbol with \"-(\" to start a barre and \"-)\" to end the barre. @end itemize" ;TODO -- change syntax to fret\string-finger (let ((definition-list (fret-parse-terse-definition-string props definition-string))) (make-fret-diagram layout (car definition-list) (cdr definition-list)))) (define (fret-parse-terse-definition-string props definition-string) "parse a fret diagram string that uses terse syntax; return a pair containing: props, modified to include the string-count determined by the definition-string a fret-indication list with the appropriate values" ;TODO -- change syntax to fret\string-finger (let* ((barre-start-list '()) (output-list '()) (new-props '()) (items (string-split definition-string #\;)) (string-count (- (length items) 1))) (let parse-item ((myitems items)) (if (not (null? (cdr myitems))) (let* ((test-string (car myitems)) (current-string (- (length myitems) 1)) (indicators (string-split test-string #\ ))) (let parse-indicators ((myindicators indicators)) (if (not (eq? '() myindicators)) (let* ((this-list (string-split (car myindicators) #\-)) (max-element-index (- (length this-list) 1)) (last-element (car (list-tail this-list max-element-index))) (fret (if (string->number (car this-list)) (string->number (car this-list)) (car this-list)))) (if (equal? last-element "(") (begin (set! barre-start-list (cons-fret (list current-string fret) barre-start-list)) (set! this-list (list-head this-list max-element-index)))) (if (equal? last-element ")") (let* ((this-barre (get-sub-list fret barre-start-list)) (insert-index (- (length this-barre) 1))) (set! output-list (cons-fret (cons* 'barre (car this-barre) current-string (cdr this-barre)) output-list)) (set! this-list (list-head this-list max-element-index)))) (if (number? fret) (set! output-list (cons-fret (cons* 'place-fret current-string (drop-paren (numerify this-list))) output-list)) (if (equal? (car this-list) "x" ) (set! output-list (cons-fret (list 'mute current-string) output-list)) (set! output-list (cons-fret (list 'open current-string) output-list)))) (parse-indicators (cdr myindicators))))) (parse-item (cdr myitems))))) (set! new-props (acons 'string-count string-count new-props)) `(,(cons new-props props) . ,output-list))) (define (drop-paren item-list) " drop a final parentheses from a fret indication list resulting from a terse string specification of barre." (if (> (length item-list) 0) (let* ((max-index (- (length item-list) 1)) (last-element (car (list-tail item-list max-index)))) (if (or (equal? last-element ")") (equal? last-element "(")) (list-head item-list max-index) item-list)) item-list)) (define (get-sub-list value master-list) " Get a sub-list whose cadr is equal to @var{value} from @var{master-list}" (if (eq? master-list '()) #f (let ((sublist (car master-list))) (if (equal? (cadr sublist) value) sublist (get-sub-list value (cdr master-list))))))