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 init  . args)
  41   (let*
  42       ((p (apply ly:make-prob (append
  43                                (list 'page init)
  44                                args))))
  45
  46     (page-set-property! p 'head-stencil (page-header p))
  47     (page-set-property! p 'foot-stencil (page-footer p))
  48
  49     p))
  50
  51 (define page-property ly:prob-property)
  52 (define page-set-property! ly:prob-set-property!)
  53 (define (page-property? page sym)
  54   (eq? #t (page-property page sym)))
  55 (define (page? x)  (ly:prob-type? x 'page))
  56
  57
  58 ;; define accessors.
  59 (for-each
  60  (lambda (j)
  61    (module-define!
  62     page-module
  63     (string->symbol (format "page-~a" j))
  64     (lambda (pg)
  65       (page-property pg j))))
  66
  67  '(page-number prev lines force penalty lines))
  68
  69 (define (page-system-numbers page)
  70   (map (lambda (ps) (ly:prob-property ps 'number))
  71        (page-lines page)))
  72
  73 (define (page-translate-systems page)
  74   (for-each
  75
  76    (lambda (sys-off)
  77      (let*
  78          ((sys (car sys-off))
  79           (off (cadr sys-off)))
  80
  81        (if (not (number? (ly:prob-property sys 'Y-offset)))
  82            (ly:prob-set-property! sys 'Y-offset off))))
  83
  84    (zip (page-property page 'lines)
  85         (page-property page 'configuration))))
  86
  87 (define (annotate-page layout stencil)
  88   (let ((top-margin (ly:output-def-lookup layout 'top-margin))
  89         (paper-height (ly:output-def-lookup layout 'paper-height))
  90         (bottom-margin (ly:output-def-lookup layout 'bottom-margin))
  91         (add-stencil (lambda (y)
  92                        (set! stencil
  93                              (ly:stencil-add stencil
  94                                              (ly:stencil-translate-axis y 6 X))))))
  95     (add-stencil
  96      (ly:stencil-translate-axis
  97       (annotate-y-interval layout "paper-height"
  98                            (cons (- paper-height) 0)
  99                            #t)
 100       1 X))
 101     (add-stencil
 102      (ly:stencil-translate-axis
 103       (annotate-y-interval layout "top-margin"
 104                            (cons (- top-margin) 0)
 105                            #t)
 106       2 X))
 107     (add-stencil
 108      (ly:stencil-translate-axis
 109       (annotate-y-interval layout "bottom-margin"
 110                            (cons (- paper-height) (- bottom-margin paper-height))
 111                            #t)
 112       2 X))
 113     stencil))
 114
 115 (define (annotate-space-left page)
 116   (let*
 117       ((p-book (page-property page 'paper-book))
 118        (layout (ly:paper-book-paper p-book))
 119        (arrow (annotate-y-interval layout
 120                                    "space left"
 121                                    (cons (- 0.0
 122                                             (page-property page 'bottom-edge)
 123                                             (let ((foot (page-property page 'foot-stencil)))
 124                                               (if (and (ly:stencil? foot)
 125                                                        (not (ly:stencil-empty? foot)))
 126                                                   (car (ly:stencil-extent foot Y))
 127                                                   0.0)))
 128                                          (page-property page  'bottom-system-edge))
 129                                    #t)))
 130
 131     (set! arrow (ly:stencil-translate-axis arrow 8 X))
 132
 133     arrow))
 134
 135 \f
 136
 137
 138 (define (page-headfoot layout scopes number
 139                        sym separation-symbol dir last?)
 140
 141   "Create a stencil including separating space."
 142
 143   (let* ((header-proc (ly:output-def-lookup layout sym))
 144          (sep (ly:output-def-lookup layout separation-symbol))
 145          (stencil (ly:make-stencil "" '(0 . 0) '(0 . 0)))
 146          (head-stencil
 147           (if (procedure? header-proc)
 148               (header-proc layout scopes number last?)
 149               #f))
 150          )
 151
 152     (if (and (number? sep)
 153              (ly:stencil? head-stencil)
 154              (not (ly:stencil-empty? head-stencil)))
 155
 156         (begin
 157           (set! head-stencil
 158                 (ly:stencil-combine-at-edge
 159                  stencil Y dir head-stencil
 160                  sep 0.0))
 161
 162
 163           ;; add arrow markers
 164           (if (or (annotate? layout)
 165                   (ly:output-def-lookup layout 'annotate-headers #f))
 166               (set! head-stencil
 167                     (ly:stencil-add
 168                      (ly:stencil-translate-axis
 169                       (annotate-y-interval layout
 170                                            (symbol->string separation-symbol)
 171                                            (cons (min 0 (* dir sep))
 172                                                  (max 0 (* dir sep)))
 173                                            #t)
 174                       (/ (ly:output-def-lookup layout 'line-width) 2)
 175                       X)
 176                      (if (= dir UP)
 177                          (ly:stencil-translate-axis
 178                           (annotate-y-interval layout
 179                                               "page-top-space"
 180                                               (cons
 181                                                (- (min 0 (* dir sep))
 182                                                   (ly:output-def-lookup layout 'page-top-space))
 183                                                (min 0 (* dir sep)))
 184                                               #t)
 185                           (+ 7 (interval-center (ly:stencil-extent head-stencil X))) X)
 186                          empty-stencil
 187                          )
 188                      head-stencil
 189                      ))
 190               )))
 191
 192     head-stencil))
 193
 194 (define (page-header-or-footer page dir)
 195     (let*
 196       ((p-book (page-property page 'paper-book))
 197        (layout (ly:paper-book-paper p-book))
 198        (scopes (ly:paper-book-scopes p-book))
 199        (lines (page-lines page))
 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
 225        (lmargin (ly:output-def-lookup layout 'left-margin))
 226        (left-margin (if lmargin
 227                        lmargin
 228                        (/ (- paper-width
 229                              (ly:output-def-lookup layout 'line-width)) 2)))
 230        (bottom-edge (- paper-height
 231                        (ly:output-def-lookup layout 'bottom-margin)) )
 232        (top-margin (ly:output-def-lookup layout 'top-margin))
 233        )
 234
 235     `((paper-height . ,paper-height)
 236       (paper-width . ,paper-width)
 237       (left-margin . ,left-margin)
 238       (top-margin . ,top-margin)
 239       (bottom-edge . ,bottom-edge)
 240       )))
 241
 242 (define (make-page-stencil page)
 243   "Construct a stencil representing the page from LINES.
 244
 245  Offsets is a list of increasing numbers. They must be negated to
 246 create offsets.
 247 "
 248
 249
 250
 251   (page-translate-systems page)
 252   (let*
 253       ((p-book (page-property page 'paper-book))
 254        (prop (lambda (sym) (page-property page sym)))
 255        (layout (ly:paper-book-paper p-book))
 256        (scopes (ly:paper-book-scopes p-book))
 257        (lines (page-lines page))
 258        (number (page-page-number page))
 259
 260        ;; TODO: naming paper-height/paper-width not analogous to TeX.
 261
 262
 263        (system-xoffset (ly:output-def-lookup layout 'horizontal-shift 0.0))
 264        (system-separator-markup (ly:output-def-lookup layout 'systemSeparatorMarkup))
 265        (system-separator-stencil (if (markup? system-separator-markup)
 266                                      (interpret-markup layout
 267                                                        (layout-extract-page-properties layout)
 268                                                        system-separator-markup)
 269                                      #f))
 270
 271        (head-height (if (ly:stencil? (prop 'head-stencil))
 272                         (interval-length (ly:stencil-extent (prop 'head-stencil) Y))
 273                         0.0))
 274
 275        (page-stencil (ly:make-stencil
 276                       '()
 277                       (cons (prop 'left-margin) (prop 'paper-width))
 278                       (cons (- (prop 'top-margin)) 0)))
 279
 280        (last-system #f)
 281        (last-y 0.0)
 282        (add-to-page (lambda (stencil x y)
 283                       (set! page-stencil
 284                             (ly:stencil-add page-stencil
 285                                             (ly:stencil-translate stencil
 286                                                                   (cons
 287                                                                    (+ system-xoffset x)
 288                                                                    (- 0 head-height y (prop 'top-margin)))
 289
 290                                                                   )))))
 291        (add-system
 292         (lambda (system)
 293           (let* ((stencil (paper-system-stencil system))
 294                  (y (ly:prob-property system 'Y-offset))
 295                  (is-title (paper-system-title?
 296                             system)))
 297             (add-to-page stencil
 298                          (ly:prob-property system 'X-offset 0.0)
 299                          y)
 300             (if (and (ly:stencil? system-separator-stencil)
 301                      last-system
 302                      (not (paper-system-title? system))
 303                      (not (paper-system-title? last-system)))
 304                 (add-to-page
 305                  system-separator-stencil
 306                  0
 307                  (average (- last-y
 308                              (car (paper-system-staff-extents last-system)))
 309                           (- y
 310                              (cdr (paper-system-staff-extents system))))))
 311             (set! last-system system)
 312             (set! last-y y))))
 313        (head (prop 'head-stencil))
 314        (foot (prop 'foot-stencil))
 315        )
 316
 317     (if (and
 318          (or (annotate? layout)
 319              (ly:output-def-lookup layout 'annotate-systems #f))
 320          (pair? lines))
 321
 322         (begin
 323           (for-each (lambda (sys next-sys)
 324                       (paper-system-annotate sys next-sys layout))
 325                     lines
 326                     (append (cdr lines) (list #f)))
 327           (paper-system-annotate-last (car (last-pair lines)) layout)))
 328
 329     (set! page-stencil (ly:stencil-combine-at-edge
 330                         page-stencil Y DOWN
 331                         (if (and
 332                              (ly:stencil? head)
 333                              (not (ly:stencil-empty? head)))
 334                             head
 335                             (ly:make-stencil "" (cons 0 0) (cons 0 0)))
 336                             0. 0.))
 337
 338     (map add-system lines)
 339
 340     (ly:prob-set-property! page 'bottom-system-edge
 341                            (car (ly:stencil-extent page-stencil Y)))
 342     (ly:prob-set-property! page 'space-left
 343                            (+ (prop 'bottom-edge)
 344                               (prop 'bottom-system-edge)
 345                               (if (and (ly:stencil? foot)
 346                                        (not (ly:stencil-empty? foot)))
 347                                   (car (ly:stencil-extent foot Y))
 348                                   0.0)))
 349
 350     (if (annotate? layout)
 351         (set! page-stencil
 352               (ly:stencil-add page-stencil
 353                               (annotate-space-left page))))
 354
 355     (if (and (ly:stencil? foot)
 356              (not (ly:stencil-empty? foot)))
 357         (set! page-stencil
 358               (ly:stencil-add
 359                page-stencil
 360                (ly:stencil-translate
 361                 foot
 362                 (cons 0
 363                       (+ (- (prop 'bottom-edge))
 364                          (- (car (ly:stencil-extent foot Y)))))))))
 365
 366     (set! page-stencil
 367           (ly:stencil-translate page-stencil (cons (prop 'left-margin) 0)))
 368
 369     ;; annotation.
 370     (if (or (annotate? layout)
 371             (ly:output-def-lookup layout 'annotate-page #f))
 372         (set! page-stencil (annotate-page layout page-stencil)))
 373
 374     page-stencil))
 375
 376
 377 (define-public (page-stencil page)
 378   (if (not (ly:stencil? (page-property page 'stencil)))
 379
 380       ;; todo: make tweakable.
 381       ;; via property + callbacks.
 382
 383       (page-set-property! page 'stencil (make-page-stencil page)))
 384   (page-property page 'stencil))
 385
 386 (define (calc-printable-height page)
 387   "Printable area for music and titles; matches default-page-make-stencil."
 388   (let*
 389       ((p-book (page-property page 'paper-book))
 390        (layout (ly:paper-book-paper p-book))
 391        (h (- (ly:output-def-lookup layout 'paper-height)
 392                (ly:output-def-lookup layout 'top-margin)
 393                (ly:output-def-lookup layout 'bottom-margin)))
 394
 395        (head (page-property page 'head-stencil))
 396        (foot (page-property page 'foot-stencil))
 397        (available
 398         (- h (if (ly:stencil? head)
 399                  (interval-length (ly:stencil-extent head Y))
 400                  0)
 401            (if (ly:stencil? foot)
 402                (interval-length (ly:stencil-extent foot Y))
 403                0))))
 404
 405     ;; (display (list "\n available" available head foot))
 406     available))
 407
 408 (define (page-printable-height page)
 409   (if (not (number? (page-property page 'printable-height)))
 410       (page-set-property! page 'printable-height (calc-printable-height page)))
 411
 412   (page-property page 'printable-height))
 413