1 ;;;; page-layout.scm -- page layout functions
3 ;;;; source file of the GNU LilyPond music typesetter
5 ;;;; (c) 2004 Jan Nieuwenhuizen <janneke@gnu.org>
7 (define (ly:modules-lookup modules sym)
8 (let ((v (module-variable (car modules) sym)))
9 (if (and v (variable-bound? v) (variable-ref v))
11 (if (module? (cdr modules)) (ly:modules-lookup (cdr modules) sym)))))
13 (define (page-properties paper)
14 (list (append `((linewidth . ,(ly:paper-get-number
16 (ly:paper-lookup paper 'text-font-defaults))))
18 (define-public (book-title paper scopes)
19 "Generate book title from header strings."
22 (let ((x (ly:modules-lookup scopes sym)))
23 (if (and x (not (unspecified? x))) x "")))
25 (let ((props (page-properties paper)))
31 (#:override '(baseline-skip . 4)
34 (#:normalsize (get 'dedication))
36 (#:huge #:bigger #:bigger #:bigger #:bigger #:bold (get 'title))
37 #:override '(baseline-skip . 3)
40 (#:large #:bigger #:bigger #:bold (get 'subtitle))
41 #:fill-line (#:bigger #:bigger #:bold (get 'subsubtitle)))
42 #:override '(baseline-skip . 5)
44 #:override '(baseline-skip . 2.5)
47 (#:bigger (get 'poet) #:large #:bigger #:caps (get 'composer))
48 #:fill-line (#:bigger (get 'texttranslator) #:bigger (get 'opus))
50 (#:bigger (get 'meter) #:bigger (get 'arranger))
52 #:fill-line (#:large #:bigger (get 'instrument))
54 #:fill-line (#:large #:bigger #:caps (get 'piece) ""))))))))
56 (define-public (user-title paper markup)
57 "Generate book title from header markup."
59 (let ((props (page-properties paper))
60 (baseline-skip (chain-assoc-get 'baseline-skip props 2)) )
61 (stack-lines DOWN 0 BASELINE-SKIP
62 (list (interpret-markup paper props markup))))))
64 (define-public (score-title paper scopes)
65 "Generate score title from header strings."
68 (let ((x (ly:modules-lookup scopes sym)))
69 (if (and x (not (unspecified? x))) x "")))
71 (let ((props (page-properties paper)))
77 (#:override '(baseline-skip . 4)
81 #:fill-line (#:large #:bigger #:caps (get 'piece) "")))))))
83 (define-public (make-header paper page-number)
84 (let ((props (page-properties paper) ))
85 (interpret-markup paper props
87 ;; FIXME: font not found
88 ;; ("" #:bold (number->string page-number))))))
89 ("" (number->string page-number))))))
91 (define-public (make-footer paper page-number)
92 (let ((props (page-properties paper)))
94 (interpret-markup paper props
95 (markup #:fill-line ("" (number->string page-number))))))
99 (string-append "Engraved by LilyPond (version " (lilypond-version) ")"))
101 (define-public (make-tagline paper scopes)
102 (let* ((props (page-properties paper))
103 (tagline-var (ly:modules-lookup scopes 'tagline))
104 (tagline (if (markup? tagline-var) tagline-var TAGLINE)))
106 (cond ((string? tagline)
107 (if (not (equal? tagline ""))
108 (interpret-markup paper props
109 (markup #:fill-line (tagline "")))))
110 ((markup? tagline) (interpret-markup paper props tagline)))))
112 (define-public (make-copyright paper scopes)
113 (let ((props (page-properties paper))
114 (copyright (ly:modules-lookup scopes 'copyright)))
116 (cond ((string? copyright)
117 (if (not (equal? copyright ""))
118 (interpret-markup paper props
119 (markup #:fill-line (copyright "")))))
120 ((markup? copyright) (interpret-markup paper props copyright)))))
123 ;;; optimal page breaking
125 ;;; This is not optimal page breaking, this is optimal distribution of
126 ;;; lines over pages; line breaks are a given.
130 ;;; + \pagebreak, \nopagebreak
132 ;;; - short circut SCORE=-1 (dismiss path)
135 (use-modules (oop goops describe))
137 (define-class <break-node> ()
138 (prev #:init-value '() #:accessor node-prev #:init-keyword #:prev)
139 (line #:init-value 'barf #:accessor node-line #:init-keyword #:line)
140 (page #:init-value 0 #:accessor node-page #:init-keyword #:page)
141 (score #:init-value 0 #:accessor node-score #:init-keyword #:score)
142 (height #:init-value 0 #:accessor node-height #:init-keyword #:score))
144 (define (node-line-number node)
145 (let ((line (node-line node)))
147 (ly:paper-line-number line))))
149 (define (node-break-score node)
150 (let ((line (node-line node)))
152 (ly:paper-line-break-score line))))
154 (define (make-node prev line page score)
155 (make <break-node> #:prev prev #:line line #:page page #:score score))
157 ;; print debuggging stuff
159 (define MAX-CRAMP -5)
161 (define-public (ly:optimal-page-breaks lines book-height text-height
162 first-diff last-diff)
164 ;; FIXME: may need some tweaking: square, cubic
165 (define (height-score available used)
166 (let* ((empty (- available used))
167 (norm-empty (* empty (/ 100 available))))
169 (if (< (/ empty available) MAX-CRAMP)
170 ;; cannot fill more than MAX-CRAMP
172 ;; overfull page is still worse by a power
173 (* -1 norm-empty norm-empty norm-empty))
174 (* norm-empty norm-empty))))
176 (define (page-height page-number page-count)
177 (let ((h text-height))
178 (if (= page-number 1)
179 (set! h (+ h first-diff)))
180 (if (= page-number page-count)
181 (set! h (+ h last-diff)))
184 (define (cumulative-height lines)
185 (apply + (map ly:paper-line-height lines)))
187 (define (get-path node)
190 (cons node (get-path (node-prev node)))))
192 (define (add-scores . lst)
193 (if (null? (filter (lambda (x) (> 0 x)) lst))
197 (define (density-variance nodes)
198 (define (sqr x) (* x x))
199 (define (density node)
200 (let ((p (page-height (node-page node) (node-page (car nodes))))
201 (h (node-height node)))
202 (if (and p h) (* (- p h) (/ h 100)) 0)))
203 (let* ((densities (map density nodes))
204 (mean (/ (apply + densities) (length densities)))
205 (diff (map (lambda (x) (- x mean)) densities))
206 (var (map sqr diff)))
209 (format (current-error-port) "densities: ~S\n" densities)
210 (format (current-error-port) "mean: ~S\n" mean)
211 (format (current-error-port) "diff: ~S\n" diff)
212 (format (current-error-port) "density-var: ~S\n" var)))
215 (define (walk-paths best node lines nodes paths)
218 (format (current-error-port) "node: ")
220 (let* ((height (cumulative-height lines))
221 (page (page-height (node-page node) (if (= (node-score node) 0)
222 (node-page node) 0))))
223 (set! (node-height node) height)
225 (let* ((break-score (node-break-score node))
226 (density-score (if (null? paths) 0
227 ;; FIXME: 5 may need some tweaking
228 (* 5 (density-variance
229 (cons node (get-path (car paths)))))))
230 (page-score (height-score page height))
231 (this-score (add-scores page-score break-score density-score))
232 (path-score (if (null? paths) 0 (node-score (car paths))))
233 (score (add-scores path-score this-score))
234 (nbpn (+ (if (null? paths) 0 (node-page (car paths))) 1)))
238 (format (current-error-port) "lines: ~S\n" lines)
239 (format (current-error-port) "page-height: ~f\n" page)
240 (format (current-error-port) "height: ~f\n" height)
241 (format (current-error-port) "break-score: ~f\n" break-score)
242 (format (current-error-port) "density-score: ~f\n" density-score)
243 (format (current-error-port) "this-score: ~f\n" this-score)
244 (format (current-error-port) "path: ~f ~S\n" path-score
245 (if (null? paths) '()
246 (map node-line-number (get-path (car paths)))))
247 (format (current-error-port) "score: ~f\n" score)
248 (format (current-error-port) "best: ~f ~S\n" (node-score best)
249 (map node-line-number (get-path best)))
250 (format (current-error-port) "nbpn: ~f\n" nbpn)
251 (format (current-error-port) "breaking after: ~S scores: ~S\n"
252 (node-line-number node)
255 (set! (node-score node) score)
256 (if (and (>= score 0)
257 (or (< score (node-score best))
258 (= (node-score best) -1)
260 (= (node-score best) 0)))
261 ;; FIXME: (set! best node) ?
263 (set! (node-score best) score)
264 (set! (node-page best) nbpn)
265 (set! (node-prev best) node)
266 (set! (node-height best) height)
269 (format (current-error-port) "NEW BEST: ~f ~S\n"
271 (map node-line-number (get-path best)))
272 (format (current-error-port) "breaking after: ~S scores: ~S\n"
273 (node-line-number node)
276 (format (current-error-port) "BEST still better\n")))
277 (if (null? (cdr nodes))
279 (walk-paths best (car paths) (cons (node-line node) lines)
280 (cdr nodes) (cdr paths))))))
282 (define (walk-lines lines nodes paths)
284 (if (null? (cdr lines))
286 (let ((next (make-node (car nodes) (cadr lines) 0 0))
291 (format (current-error-port) "\n***********TOP*************")
293 (newline (current-error-port)))
295 (let ((break (walk-paths next best
296 (list (node-line best))
301 (format (current-error-port) "break: ~f ~S\n"
303 (map node-line-number (get-path break))))
304 (walk-lines (cdr lines)
305 (cons (make-node '() (cadr lines) 0 0) nodes)
306 (cons break paths))))))
308 (let* ((dummy (make-node '() '() 0 0))
309 (result (walk-lines lines
310 (list (make-node dummy (car lines) 0 0))
312 (path (get-path (car result)))
313 ;; CDR: junk dummy node
314 (breaks (cdr (reverse (map node-line-number path)))))
316 (format (current-error-port) "breaks: ~S\n" breaks)
317 (force-output (current-error-port))
318 (list->vector breaks)))