scm/page.scm

   1 ;;
   2 ;; page.scm -- implement Page stuff.
   3 ;;
   4 ;; source file of the GNU LilyPond music typesetter
   5 ;;
   6 ;; (c) 2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 ;;
   8
   9 (define-module (scm page)
  10
  11   #:export (make-page
  12             page-property
  13             page-set-property!
  14             page-prev
  15             page-printable-height
  16             layout->page-init
  17             page-lines
  18             page-force
  19             page-penalty
  20             page-configuration
  21             page-lines
  22             page-page-number
  23             page-system-numbers
  24             page-stencil
  25             page-free-height
  26             page?
  27             ))
  28
  29 (use-modules (lily)
  30              (scm paper-system)
  31              (srfi srfi-1))
  32
  33
  34 (define (annotate? layout)
  35   (eq? #t (ly:output-def-lookup layout 'annotate-spacing)))
  36
  37
  38 (define page-module (current-module))
  39
  40 (define (make-page paper-book  . args)
  41   (let*
  42       ((p (apply ly:make-prob (append
  43                                (list 'page (layout->page-init (ly:paper-book-paper paper-book))
  44                                      'paper-book paper-book)
  45                                args))))
  46
  47     (page-set-property! p 'head-stencil (page-header p))
  48     (page-set-property! p 'foot-stencil (page-footer p))
  49
  50     p))
  51
  52 (define page-property ly:prob-property)
  53 (define page-set-property! ly:prob-set-property!)
  54 (define (page-property? page sym)
  55   (eq? #t (page-property page sym)))
  56 (define (page? x)  (ly:prob-type? x 'page))
  57
  58
  59 ;; define accessors.
  60 (for-each
  61  (lambda (j)
  62    (module-define!
  63     page-module
  64     (string->symbol (format "page-~a" j))
  65     (lambda (pg)
  66       (page-property pg j))))
  67
  68  '(page-number prev lines force penalty lines))
  69
  70 (define (page-system-numbers page)
  71   (map (lambda (ps) (ly:prob-property ps 'number))
  72        (page-lines page)))
  73
  74 (define (page-translate-systems page)
  75   (for-each
  76
  77    (lambda (sys-off)
  78      (let*
  79          ((sys (car sys-off))
  80           (off (cadr sys-off)))
  81
  82        (if (not (number? (ly:prob-property sys 'Y-offset)))
  83            (ly:prob-set-property! sys 'Y-offset off))))
  84
  85    (zip (page-property page 'lines)
  86         (page-property page 'configuration))))
  87
  88 (define (annotate-page layout stencil)
  89   (let ((top-margin (ly:output-def-lookup layout 'top-margin))
  90         (paper-height (ly:output-def-lookup layout 'paper-height))
  91         (bottom-margin (ly:output-def-lookup layout 'bottom-margin))
  92         (add-stencil (lambda (y)
  93                        (set! stencil
  94                              (ly:stencil-add stencil
  95                                              (ly:stencil-translate-axis y 6 X))))))
  96     (add-stencil
  97      (ly:stencil-translate-axis
  98       (annotate-y-interval layout "paper-height"
  99                            (cons (- paper-height) 0)
 100                            #t)
 101       1 X))
 102     (add-stencil
 103      (ly:stencil-translate-axis
 104       (annotate-y-interval layout "top-margin"
 105                            (cons (- top-margin) 0)
 106                            #t)
 107       2 X))
 108     (add-stencil
 109      (ly:stencil-translate-axis
 110       (annotate-y-interval layout "bottom-margin"
 111                            (cons (- paper-height) (- bottom-margin paper-height))
 112                            #t)
 113       2 X))
 114     stencil))
 115
 116 (define (annotate-space-left page)
 117   (let*
 118       ((paper-book (page-property page 'paper-book))
 119        (layout (ly:paper-book-paper paper-book))
 120        (arrow (annotate-y-interval layout
 121                                    "space left"
 122                                    (cons (- 0.0
 123                                             (page-property page 'bottom-edge)
 124                                             (let ((foot (page-property page 'foot-stencil)))
 125                                               (if (and (ly:stencil? foot)
 126                                                        (not (ly:stencil-empty? foot)))
 127                                                   (car (ly:stencil-extent foot Y))
 128                                                   0.0)))
 129                                          (page-property page  'bottom-system-edge))
 130                                    #t)))
 131
 132     (set! arrow (ly:stencil-translate-axis arrow 8 X))
 133
 134     arrow))
 135
 136 \f
 137
 138
 139 (define (page-headfoot layout scopes number
 140                        sym separation-symbol dir last?)
 141
 142   "Create a stencil including separating space."
 143
 144   (let* ((header-proc (ly:output-def-lookup layout sym))
 145          (sep (ly:output-def-lookup layout separation-symbol))
 146          (stencil (ly:make-stencil "" '(0 . 0) '(0 . 0)))
 147          (head-stencil
 148           (if (procedure? header-proc)
 149               (header-proc layout scopes number last?)
 150               #f))
 151          )
 152
 153     (if (and (number? sep)
 154              (ly:stencil? head-stencil)
 155              (not (ly:stencil-empty? head-stencil)))
 156
 157         (begin
 158           (set! head-stencil
 159                 (ly:stencil-combine-at-edge
 160                  stencil Y dir head-stencil
 161                  sep 0.0))
 162
 163
 164           ;; add arrow markers
 165           (if (or (annotate? layout)
 166                   (ly:output-def-lookup layout 'annotate-headers #f))
 167               (set! head-stencil
 168                     (ly:stencil-add
 169                      (ly:stencil-translate-axis
 170                       (annotate-y-interval layout
 171                                            (symbol->string separation-symbol)
 172                                            (cons (min 0 (* dir sep))
 173                                                  (max 0 (* dir sep)))
 174                                            #t)
 175                       (/ (ly:output-def-lookup layout 'line-width) 2)
 176                       X)
 177                      (if (= dir UP)
 178                          (ly:stencil-translate-axis
 179                           (annotate-y-interval layout
 180                                               "page-top-space"
 181                                               (cons
 182                                                (- (min 0 (* dir sep))
 183                                                   (ly:output-def-lookup layout 'page-top-space))
 184                                                (min 0 (* dir sep)))
 185                                               #t)
 186                           (+ 7 (interval-center (ly:stencil-extent head-stencil X))) X)
 187                          empty-stencil
 188                          )
 189                      head-stencil
 190                      ))
 191               )))
 192
 193     head-stencil))
 194
 195 (define (page-header-or-footer page dir)
 196     (let*
 197       ((paper-book (page-property page 'paper-book))
 198        (layout (ly:paper-book-paper paper-book))
 199        (scopes (ly:paper-book-scopes paper-book))
 200        (number (page-page-number page))
 201        (last? (page-property page 'is-last))
 202        )
 203
 204       (page-headfoot layout scopes number
 205                 (if (= dir UP)
 206                     'make-header
 207                     'make-footer)
 208                 (if (= dir UP)
 209                     'head-separation
 210                     'foot-separation)
 211                 dir last?)))
 212
 213 (define (page-header page)
 214   (page-header-or-footer page UP))
 215
 216 (define (page-footer page)
 217   (page-header-or-footer page DOWN))
 218
 219 (define (layout->page-init layout)
 220   "Alist of settings for page layout"
 221   (let*
 222       ((paper-height (ly:output-def-lookup layout 'paper-height))
 223        (paper-width (ly:output-def-lookup layout 'paper-width))
 224        (lmargin (ly:output-def-lookup layout 'left-margin #f))
 225        (left-margin (if lmargin
 226                        lmargin
 227                        (/ (- paper-width
 228                              (ly:output-def-lookup layout 'line-width)) 2)))
 229        (bottom-edge (- paper-height
 230                        (ly:output-def-lookup layout 'bottom-margin)) )
 231        (top-margin (ly:output-def-lookup layout 'top-margin))
 232        )
 233
 234     `((paper-height . ,paper-height)
 235       (paper-width . ,paper-width)
 236       (left-margin . ,left-margin)
 237       (top-margin . ,top-margin)
 238       (bottom-edge . ,bottom-edge)
 239       )))
 240
 241 (define (make-page-stencil page)
 242   "Construct a stencil representing the page from PAGE."
 243
 244
 245   (page-translate-systems page)
 246   (let*
 247       ((paper-book (page-property page 'paper-book))
 248        (prop (lambda (sym) (page-property page sym)))
 249        (layout (ly:paper-book-paper paper-book))
 250        (scopes (ly:paper-book-scopes paper-book))
 251        (lines (page-lines page))
 252        (number (page-page-number page))
 253
 254        ;; TODO: naming paper-height/paper-width not analogous to TeX.
 255
 256        (system-xoffset (ly:output-def-lookup layout 'horizontal-shift 0.0))
 257        (system-separator-markup (ly:output-def-lookup layout 'systemSeparatorMarkup))
 258        (system-separator-stencil (if (markup? system-separator-markup)
 259                                      (interpret-markup layout
 260                                                        (layout-extract-page-properties layout)
 261                                                        system-separator-markup)
 262                                      #f))
 263
 264        (head-height (if (ly:stencil? (prop 'head-stencil))
 265                         (interval-length (ly:stencil-extent (prop 'head-stencil) Y))
 266                         0.0))
 267
 268        (page-stencil (ly:make-stencil '()))
 269
 270        (last-system #f)
 271        (last-y 0.0)
 272        (add-to-page (lambda (stencil x y)
 273                       (set! page-stencil
 274                             (ly:stencil-add page-stencil
 275                                             (ly:stencil-translate stencil
 276                                                                   (cons
 277                                                                    (+ system-xoffset x)
 278                                                                    (- 0 head-height y (prop 'top-margin)))
 279
 280                                                                   )))))
 281        (add-system
 282         (lambda (system)
 283           (let* ((stencil (paper-system-stencil system))
 284                  (y (ly:prob-property system 'Y-offset))
 285                  (is-title (paper-system-title?
 286                             system)))
 287             (add-to-page stencil
 288                          (ly:prob-property system 'X-offset 0.0)
 289                          y)
 290             (if (and (ly:stencil? system-separator-stencil)
 291                      last-system
 292                      (not (paper-system-title? system))
 293                      (not (paper-system-title? last-system)))
 294                 (add-to-page
 295                  system-separator-stencil
 296                  0
 297                  (average (- last-y
 298                              (car (paper-system-staff-extents last-system)))
 299                           (- y
 300                              (cdr (paper-system-staff-extents system))))))
 301             (set! last-system system)
 302             (set! last-y y))))
 303        (head (prop 'head-stencil))
 304        (foot (prop 'foot-stencil))
 305        )
 306
 307     (if (and
 308          (or (annotate? layout)
 309              (ly:output-def-lookup layout 'annotate-systems #f))
 310          (pair? lines))
 311
 312         (begin
 313           (for-each (lambda (sys next-sys)
 314                       (paper-system-annotate sys next-sys layout))
 315                     lines
 316                     (append (cdr lines) (list #f)))
 317           (paper-system-annotate-last (car (last-pair lines)) layout)))
 318
 319     (if (and
 320          (ly:stencil? head)
 321          (not (ly:stencil-empty? head)))
 322
 323         (set! page-stencil (ly:stencil-add page-stencil
 324                                            (ly:stencil-translate-axis head
 325                                                                       (- 0 head-height (prop 'top-margin)) Y))))
 326
 327     (map add-system lines)
 328
 329
 330     (ly:prob-set-property! page 'bottom-system-edge
 331                            (car (ly:stencil-extent page-stencil Y)))
 332     (ly:prob-set-property! page 'space-left
 333                            (+ (prop 'bottom-edge)
 334                               (prop 'bottom-system-edge)
 335                               (if (and (ly:stencil? foot)
 336                                        (not (ly:stencil-empty? foot)))
 337                                   (car (ly:stencil-extent foot Y))
 338                                   0.0)))
 339
 340     (if (annotate? layout)
 341         (set! page-stencil
 342               (ly:stencil-add page-stencil
 343                               (annotate-space-left page))))
 344
 345     (if (and (ly:stencil? foot)
 346              (not (ly:stencil-empty? foot)))
 347         (set! page-stencil
 348               (ly:stencil-add
 349                page-stencil
 350                (ly:stencil-translate
 351                 foot
 352                 (cons 0
 353                       (+ (- (prop 'bottom-edge))
 354                          (- (car (ly:stencil-extent foot Y)))))))))
 355
 356     (set! page-stencil
 357           (ly:stencil-translate page-stencil (cons (prop 'left-margin) 0)))
 358
 359     ;; annotation.
 360     (if (or (annotate? layout)
 361             (ly:output-def-lookup layout 'annotate-page #f))
 362         (set! page-stencil (annotate-page layout page-stencil)))
 363
 364
 365     page-stencil))
 366
 367
 368 (define-public (page-stencil page)
 369   (if (not (ly:stencil? (page-property page 'stencil)))
 370
 371       ;; todo: make tweakable.
 372       ;; via property + callbacks.
 373
 374       (page-set-property! page 'stencil (make-page-stencil page)))
 375   (page-property page 'stencil))
 376
 377 (define (calc-printable-height page)
 378   "Printable area for music and titles; matches default-page-make-stencil."
 379   (let*
 380       ((paper-book (page-property page 'paper-book))
 381        (layout (ly:paper-book-paper paper-book))
 382        (h (- (ly:output-def-lookup layout 'paper-height)
 383                (ly:output-def-lookup layout 'top-margin)
 384                (ly:output-def-lookup layout 'bottom-margin)))
 385
 386        (head (page-property page 'head-stencil))
 387        (foot (page-property page 'foot-stencil))
 388        (available
 389         (- h (if (ly:stencil? head)
 390                  (interval-length (ly:stencil-extent head Y))
 391                  0)
 392            (if (ly:stencil? foot)
 393                (interval-length (ly:stencil-extent foot Y))
 394                0))))
 395
 396     ;; (display (list "\n available" available head foot))
 397     available))
 398
 399 (define (page-printable-height page)
 400   (if (not (number? (page-property page 'printable-height)))
 401       (page-set-property! page 'printable-height (calc-printable-height page)))
 402
 403   (page-property page 'printable-height))
 404