;;;; source file of the GNU LilyPond music typesetter
;;;;
;;;; (c) 2004--2006 Jan Nieuwenhuizen <janneke@gnu.org>
-;;;; Han-Wen Nienhuys <hanwen@cs.uu.nl>
+;;;; Han-Wen Nienhuys <hanwen@xs4all.nl>
(define-module (scm layout-page-layout)
#:use-module (srfi srfi-1)
#:use-module (scm page)
#:use-module (scm layout-page-dump)
#:use-module (lily)
- #:export (post-process-pages optimal-page-breaks make-page-from-systems))
+ #:export (post-process-pages optimal-page-breaks make-page-from-systems
+ page-breaking-wrapper
+ stretchable-line? ; delete me
+ ;; utilities for writing custom page breaking functions
+ line-height line-next-space line-next-padding
+ line-minimum-distance line-ideal-distance
+ first-line-position
+ line-ideal-relative-position line-minimum-relative-position
+ line-minimum-position-on-page
+ page-maximum-space-to-fill page-maximum-space-left space-systems))
+
+; this is for 2-pass spacing. Delete me.
+(define (stretchable-line? line)
+ "Say whether a system can be stretched."
+ (not (or (ly:prob-property? line 'is-title)
+ (let ((system-extent (paper-system-staff-extents line)))
+ (= (interval-start system-extent)
+ (interval-end system-extent))))))
+
+(define (stretch-and-draw-page paper-book systems page-number ragged last)
+ (define (stretchable? sys)
+ (and (ly:grob? sys)
+ (ly:grob-property sys 'stretchable)))
+
+ (define (height-estimate sys)
+ (interval-length
+ (if (ly:grob? sys)
+ (ly:grob-property sys 'pure-Y-extent)
+ (paper-system-extent sys Y))))
+
+ (define (max-stretch sys)
+ (if (stretchable? sys)
+ (ly:grob-property sys 'max-stretch)
+ 0.0))
+
+ (define (print-system sys)
+ (if (ly:grob? sys)
+ (ly:system-print sys)
+ sys))
+
+ (define (set-line-stretch! sorted-lines rest-height space-left)
+ (if (not (null? sorted-lines))
+ (let* ((line (first sorted-lines))
+ (height (height-estimate line))
+ (stretch (min (max-stretch line)
+ (if (positive? rest-height)
+ (/ (* height space-left) rest-height)
+ 0.0))))
+ (if (stretchable? line)
+ (ly:system-stretch line stretch))
+ (set-line-stretch! (cdr sorted-lines)
+ (if (stretchable? line)
+ (- rest-height height)
+ rest-height)
+ (- space-left stretch)))))
+
+ (let* ((page (make-page paper-book
+ 'page-number page-number
+ 'is-last last))
+ (paper (ly:paper-book-paper paper-book))
+ (height (page-printable-height page))
+ ; there is a certain amount of impreciseness going on here:
+ ; the system heights are estimated, we aren't using skyline distances
+ ; yet, etc. If we overstretch because of underestimation, the result
+ ; is very bad. So we stick in some extra space, just to be sure.
+ (buffer (/ height 10.0))
+ (total-system-height (apply + (map height-estimate systems)))
+ (height-left (- height total-system-height buffer)))
+
+ (if (not ragged)
+ (set-line-stretch! (sort systems
+ (lambda (s1 s2)
+ (< (height-estimate s1)
+ (height-estimate s2))))
+ (apply + (map height-estimate
+ (filter stretchable? systems)))
+ (- (page-printable-height page)
+ total-system-height)))
+
+ (let* ((lines (map print-system systems))
+ (posns (if (null? lines)
+ (list)
+ (let* ((paper (ly:paper-book-paper paper-book))
+ (space-to-fill (page-maximum-space-to-fill
+ page lines paper))
+ (spacing (space-systems space-to-fill lines ragged paper #f)))
+ (if (and (> (length lines) 1)
+ (or (not (car spacing)) (inf? (car spacing))))
+ (begin
+ (ly:warning (_ "Can't fit systems on page -- ignoring between-system-padding"))
+ (cdr (space-systems space-to-fill lines ragged paper #t)))
+ (cdr spacing))))))
+ (page-set-property! page 'lines lines)
+ (page-set-property! page 'configuration posns)
+ page)))
+
+(define (page-breaking-wrapper paper-book)
+ "Compute line and page breaks by calling the page-breaking paper variable,
+ then performs the post process function using the page-post-process paper
+ variable. Finally, return the pages."
+ (let* ((paper (ly:paper-book-paper paper-book))
+ (pages ((ly:output-def-lookup paper 'page-breaking) paper-book)))
+ ((ly:output-def-lookup paper 'page-post-process) paper pages)
+ pages))
(define (post-process-pages layout pages)
- (if (ly:output-def-lookup layout 'write-page-layout #f)
- (write-page-breaks pages)))
+ "If the write-page-layout paper variable is true, dumps page breaks
+ and tweaks."
+
+ (let*
+ ((parser (ly:modules-lookup (list (current-module)) 'parser))
+ (output-name (ly:parser-output-name parser))
+ )
+
+ (if (ly:output-def-lookup layout 'write-page-layout #f)
+ (write-page-breaks pages output-name))))
;;;
;;; Utilities for computing line distances and positions
;;;
+(define (line-extent line)
+ "Return the extent of the line (its lowest and highest Y-coordinates)."
+ (paper-system-extent line Y))
+
+(define (line-height line)
+ "Return the system height, that is the length of its vertical extent."
+ (interval-length (line-extent line)))
+
(define (line-next-space line next-line layout)
"Return space to use between `line' and `next-line'.
`next-line' can be #f, meaning that `line' is the last line."
- (let* ((title? (paper-system-title? line))
- (next-title? (and next-line (paper-system-title? next-line))))
- (cond ((and title? next-title?)
- (ly:output-def-lookup layout 'between-title-space))
- (title?
- (ly:output-def-lookup layout 'after-title-space))
- (next-title?
- (ly:output-def-lookup layout 'before-title-space))
- (else
- (ly:prob-property
- line 'next-space
- (ly:output-def-lookup layout 'between-system-space))))))
+ (let* ((title (paper-system-title? line))
+ (next-title (and next-line (paper-system-title? next-line))))
+ (cond ((and title next-title)
+ (ly:output-def-lookup layout 'between-title-space))
+ (title
+ (ly:output-def-lookup layout 'after-title-space))
+ (next-title
+ (ly:output-def-lookup layout 'before-title-space))
+ (else
+ (ly:prob-property
+ line 'next-space
+ (ly:output-def-lookup layout 'between-system-space))))))
(define (line-next-padding line next-line layout)
"Return padding to use between `line' and `next-line'.
(ly:output-def-lookup layout 'between-system-padding)))
-(define (line-minimum-distance line next-line layout)
+(define (line-minimum-distance line next-line layout ignore-padding)
"Minimum distance between `line' reference position and `next-line'
reference position. If next-line is #f, return #f."
(and next-line
- (max 0 (- (+ (interval-end (paper-system-extent next-line Y))
- (line-next-padding line next-line layout))
- (interval-start (paper-system-extent line Y))))))
+ (let ((padding (if ignore-padding
+ 0
+ (line-next-padding line next-line layout))))
+ (if (or (ly:grob? line) (ly:grob? next-line))
+ (max 0 (+ padding
+ (- (interval-start (line-extent line))
+ (interval-end (line-extent next-line)))))
+ (max 0 (+ padding
+ (ly:paper-system-minimum-distance line next-line)))))))
-(define (line-ideal-distance line next-line layout)
+(define (line-ideal-distance line next-line layout ignore-padding)
"Ideal distance between `line' reference position and `next-line'
reference position. If next-line is #f, return #f."
(and next-line
(+ (max 0 (- (+ (interval-end (paper-system-staff-extents next-line))
- (line-next-padding line next-line layout))
- (interval-start (paper-system-staff-extents line))))
- (line-next-space line next-line layout))))
+ (if ignore-padding 0 (line-next-padding line next-line layout)))
+ (interval-start (paper-system-staff-extents line))))
+ (line-next-space line next-line layout))))
(define (first-line-position line layout)
"Position of the first line on page"
- (max (+ (ly:output-def-lookup layout 'page-top-space)
- (interval-end (paper-system-staff-extents line)))
- (interval-end (paper-system-extent line Y))))
+ (max (+ (if (ly:prob-property? line 'is-title)
+ ;; do not use page-top-space if first line is a title
+ 0.0
+ (ly:output-def-lookup layout 'page-top-space))
+ (interval-end (paper-system-staff-extents line)))
+ (interval-end (line-extent line))))
-(define (line-ideal-relative-position line prev-line layout)
+(define (line-ideal-relative-position line prev-line layout ignore-padding)
"Return ideal position of `line', relative to `prev-line' position.
`prev-line' can be #f, meaning that `line' is the first line."
(if (not prev-line)
;; first line on page
(first-line-position line layout)
;; not the first line on page
- (max (line-minimum-distance prev-line line layout)
- (line-ideal-distance prev-line line layout))))
+ (max (line-minimum-distance prev-line line layout ignore-padding)
+ (line-ideal-distance prev-line line layout ignore-padding))))
-(define (line-minimum-relative-position line prev-line layout)
+(define (line-minimum-relative-position line prev-line layout ignore-padding)
"Return position of `line', relative to `prev-line' position.
`prev-line' can be #f, meaning that `line' is the first line."
(if (not prev-line)
;; first line on page
(first-line-position line layout)
;; not the first line on page
- (line-minimum-distance prev-line line layout)))
+ (line-minimum-distance prev-line line layout ignore-padding)))
+
+(define (line-minimum-position-on-page line prev-line prev-position page)
+ "If `line' fits on `page' after `prev-line', which position on page is
+ `prev-position', then return the line's postion on page, otherwise #f.
+ `prev-line' can be #f, meaning that `line' is the first line."
+ (let* ((layout (ly:paper-book-paper (page-property page 'paper-book)))
+ (position (+ (line-minimum-relative-position line prev-line layout #f)
+ (if prev-line prev-position 0.0)))
+ (bottom-position (- position
+ (interval-start (line-extent line)))))
+ (and (or (not prev-line)
+ (< bottom-position (page-printable-height page)))
+ position)))
+
+(define (page-maximum-space-to-fill page lines paper)
+ "Return the space between the first line top position and the last line
+ bottom position. This constitutes the maximum space to fill on `page'
+ with `lines'."
+ (let ((last-line (car (last-pair lines))))
+ (- (page-printable-height page)
+ (first-line-position (first lines) paper)
+ (ly:prob-property last-line
+ 'bottom-space 0.0)
+ (- (interval-start (line-extent last-line))))))
+
+(define (page-maximum-space-left page)
+ (let ((paper (ly:paper-book-paper (page-property page 'paper-book))))
+ (let bottom-position ((lines (page-property page 'lines))
+ (prev-line #f)
+ (prev-position #f))
+ (if (null? lines)
+ (page-printable-height page)
+ (let* ((line (first lines))
+ (position (line-minimum-position-on-page
+ line prev-line prev-position page)))
+ (if (null? (cdr lines))
+ (and position
+ (- (page-printable-height page)
+ (- position
+ (interval-start (line-extent line)))))
+ (bottom-position (cdr lines) line position)))))))
;;;
-;;; Page breaking functions
+;;; Utilities for distributing systems on a page
+;;;
+
+(define (space-systems space-to-fill lines ragged paper ignore-padding)
+ "Compute lines positions on page: return force and line positions as a pair.
+ force is #f if lines do not fit on page."
+ (let* ((empty-stencil (ly:make-stencil '() '(0 . 0) '(0 . 0)))
+ (empty-prob (ly:make-prob 'paper-system (list `(stencil . ,empty-stencil))))
+ (cdr-lines (append (cdr lines)
+ (if (<= (length lines) 1)
+ (list empty-prob)
+ '())))
+ (springs (map (lambda (prev-line line)
+ (list (line-ideal-distance prev-line line paper ignore-padding)
+ (/ 1.0 (line-next-space prev-line line paper))))
+ lines
+ cdr-lines))
+ (rods (map (let ((i -1))
+ (lambda (prev-line line)
+ (set! i (1+ i))
+ (list i (1+ i)
+ (line-minimum-distance prev-line line paper ignore-padding))))
+ lines
+ cdr-lines))
+ (space-result
+ (ly:solve-spring-rod-problem springs rods space-to-fill ragged)))
+ (cons (car space-result)
+ (map (let ((topskip (first-line-position (first lines) paper)))
+ (lambda (y)
+ (+ y topskip)))
+ (cdr space-result)))))
+
+
+;;;
+;;; Page breaking function
;;;
;; Optimal distribution of
done))
(define (combine-penalties force user best-paths
- inter-system-space force-equalization-factor)
+ inter-system-space force-equalization-factor)
(let* ((prev-force (if (null? best-paths)
- 0.0
- (page-force (car best-paths))))
- (prev-penalty (if (null? best-paths)
- 0.0
- (page-penalty (car best-paths))))
+ 0.0
+ (page-force (car best-paths))))
+ (prev-penalty (if (null? best-paths)
+ 0.0
+ (page-penalty (car best-paths))))
(relative-force (/ force inter-system-space))
(abs-relative-force (abs relative-force)))
(+ (* abs-relative-force (+ abs-relative-force 1))
prev-penalty
(* force-equalization-factor (/ (abs (- prev-force force))
- inter-system-space))
+ inter-system-space))
user)))
-(define (space-systems page-height lines ragged? paper)
- "Compute lines positions on page: return force and line positions as a pair.
- force is #f if lines do not fit on page."
- (let* ((empty-stencil (ly:make-stencil '() '(0 . 0) '(0 . 0)))
- (empty-prob (ly:make-prob 'paper-system (list `(stencil . ,empty-stencil))))
- (cdr-lines (append (cdr lines)
- (if (<= (length lines) 1)
- (list empty-prob)
- '())))
- (springs (map (lambda (prev-line line)
- (list (line-ideal-distance prev-line line paper)
- (/ 1.0 (line-next-space prev-line line paper))))
- lines
- cdr-lines))
- (rods (map (let ((i -1))
- (lambda (prev-line line)
- (set! i (1+ i))
- (list i (1+ i)
- (line-minimum-distance prev-line line paper))))
- lines
- cdr-lines))
- (last-line (car (last-pair lines)))
- (topskip (first-line-position (first lines) paper))
- (space-to-fill (- page-height
- topskip
- (ly:prob-property last-line
- 'bottom-space 0.0)
- (- (interval-start (paper-system-extent
- last-line Y)))))
- (space-result
- (ly:solve-spring-rod-problem springs rods space-to-fill ragged?)))
- (cons (car space-result)
- (map (lambda (y)
- (+ y topskip))
- (cdr space-result)))))
-
-(define (make-page-from-systems paper-book lines page-number ragged? last?)
- (let*
- ((page (make-page
- paper-book
- 'lines lines
- 'page-number page-number
- 'is-last last?))
- (height (page-printable-height page))
- (posns (if (> (length lines) 0)
- (cdr (space-systems height lines ragged? (ly:paper-book-paper paper-book)))
- '())))
- (page-set-property! page 'configuration posns)
- page))
-
-(define (walk-paths done-lines best-paths current-lines last? current-best
- paper-book page-alist)
+(define (walk-paths done-lines best-paths current-lines last current-best
+ paper-book page-alist)
"Return the best optimal-page-break-node that contains
-CURRENT-LINES. DONE-LINES.reversed ++ CURRENT-LINES is a consecutive
+CURRENT-LINES. DONE-LINES.reversed ++ CURRENT-LINES is a consecutive
ascending range of lines, and BEST-PATHS contains the optimal breaks
corresponding to DONE-LINES.
CURRENT-BEST is the best result sofar, or #f."
(let* ((paper (ly:paper-book-paper paper-book))
- (this-page (make-page
- paper-book
- 'is-last last?
- 'page-number (if (null? best-paths)
- (ly:output-def-lookup paper 'first-page-number)
- (1+ (page-page-number (first best-paths))))))
- (ragged-all? (eq? #t (ly:output-def-lookup paper 'ragged-bottom)))
- (ragged-last? (eq? #t (ly:output-def-lookup paper 'ragged-last-bottom)))
- (ragged? (or ragged-all? (and ragged-last? last?)))
- (height (page-printable-height this-page))
- (vertical-spacing (space-systems height current-lines ragged? paper))
- (satisfied-constraints (car vertical-spacing))
- (force (if satisfied-constraints
- (if (and last? ragged-last?)
- 0.0
- satisfied-constraints)
- 10000))
- (positions (cdr vertical-spacing))
- (get-break-penalty (lambda (sys)
- (ly:prob-property sys 'penalty 0.0)))
- (user-nobreak-penalties (- (apply + (filter negative?
- (map get-break-penalty
- (cdr current-lines))))))
- (user-penalty (+ (max (get-break-penalty (car current-lines)) 0.0)
- user-nobreak-penalties))
- (total-penalty (combine-penalties
- force user-penalty best-paths
- (ly:output-def-lookup paper 'between-system-space)
- (ly:output-def-lookup paper 'verticalequalizationfactor 0.3)))
- (new-best (if (or (not current-best)
- (and satisfied-constraints
- (< total-penalty (page-penalty current-best))))
- (begin
- (map (lambda (x)
- (page-set-property! this-page
- (car x)
- (cdr x)))
- (list (cons 'prev (if (null? best-paths)
- #f
- (car best-paths)))
- (cons 'lines current-lines)
- (cons 'force force)
- (cons 'configuration positions)
- (cons 'penalty total-penalty)))
- this-page)
- current-best)))
+ (this-page (make-page
+ paper-book
+ 'is-last last
+ 'page-number (if (null? best-paths)
+ (ly:output-def-lookup paper 'first-page-number)
+ (1+ (page-page-number (first best-paths))))))
+ (ragged-all (eq? #t (ly:output-def-lookup paper 'ragged-bottom)))
+ (ragged-last (eq? #t (ly:output-def-lookup paper 'ragged-last-bottom)))
+ (ragged (or ragged-all (and ragged-last last)))
+ (space-to-fill (page-maximum-space-to-fill this-page current-lines paper))
+ (vertical-spacing (space-systems space-to-fill current-lines ragged paper #f))
+ (satisfied-constraints (car vertical-spacing))
+ (force (if satisfied-constraints
+ (if (and last ragged-last)
+ 0.0
+ satisfied-constraints)
+ 10000))
+ (positions (cdr vertical-spacing))
+ (get-break-penalty (lambda (sys)
+ (ly:prob-property sys 'penalty 0.0)))
+ (user-nobreak-penalties (- (apply + (filter negative?
+ (map get-break-penalty
+ (cdr current-lines))))))
+ (user-penalty (+ (max (get-break-penalty (car current-lines)) 0.0)
+ user-nobreak-penalties))
+ (total-penalty (combine-penalties
+ force user-penalty best-paths
+ (ly:output-def-lookup paper 'between-system-space)
+ (ly:output-def-lookup paper 'verticalequalizationfactor 0.3)))
+ (new-best (if (or (not current-best)
+ (and satisfied-constraints
+ (< total-penalty (page-penalty current-best))))
+ (begin
+ (map (lambda (x)
+ (page-set-property! this-page
+ (car x)
+ (cdr x)))
+ (list (cons 'prev (if (null? best-paths)
+ #f
+ (car best-paths)))
+ (cons 'lines current-lines)
+ (cons 'force force)
+ (cons 'configuration positions)
+ (cons 'penalty total-penalty)))
+ this-page)
+ current-best)))
(if #f ;; debug
- (display
- (list
- "\nuser pen " user-penalty
- "\nsatisfied-constraints" satisfied-constraints
- "\nlast? " last? "ragged?" ragged?
- "\nis-better " is-better " total-penalty " total-penalty "\n"
- "\nconfig " positions
- "\nforce " force
- "\nlines: " current-lines "\n")))
+ (display
+ (list
+ "\nuser pen " user-penalty
+ "\nsatisfied-constraints" satisfied-constraints
+ "\nlast? " last "ragged?" ragged
+ "\nis-better " is-better " total-penalty " total-penalty "\n"
+ "\nconfig " positions
+ "\nforce " force
+ "\nlines: " current-lines "\n")))
(if #f ; debug
- (display (list "\nnew-best is " (page-lines new-best)
- "\ncontinuation of "
- (if (null? best-paths)
- "start"
- (page-lines (car best-paths))))))
+ (display (list "\nnew-best is " (page-lines new-best)
+ "\ncontinuation of "
+ (if (null? best-paths)
+ "start"
+ (page-lines (car best-paths))))))
(if (and (pair? done-lines)
- ;; if this page is too full, adding another line won't help
- satisfied-constraints)
- (walk-paths (cdr done-lines) (cdr best-paths)
- (cons (car done-lines) current-lines)
- last? new-best
- paper-book page-alist)
- new-best)))
+ ;; if this page is too full, adding another line won't help
+ satisfied-constraints)
+ (walk-paths (cdr done-lines) (cdr best-paths)
+ (cons (car done-lines) current-lines)
+ last new-best
+ paper-book page-alist)
+ new-best)))
(define (walk-lines done best-paths todo paper-book page-alist)
"Return the best page breaking as a single
(if (null? todo)
(car best-paths)
(let* ((this-line (car todo))
- (last? (null? (cdr todo)))
- (next (walk-paths done best-paths (list this-line) last? #f
- paper-book page-alist)))
- (walk-lines (cons this-line done)
- (cons next best-paths)
- (cdr todo)
- paper-book
- page-alist))))
+ (last (null? (cdr todo)))
+ (next (walk-paths done best-paths (list this-line) last #f
+ paper-book page-alist)))
+ (walk-lines (cons this-line done)
+ (cons next best-paths)
+ (cdr todo)
+ paper-book
+ page-alist))))
(define-public (optimal-page-breaks paper-book)
"Return pages as a list starting with 1st page. Each page is a 'page Prob."
(let* ((paper (ly:paper-book-paper paper-book))
(lines (ly:paper-book-systems paper-book))
- (page-alist (layout->page-init paper))
- (force-equalization-factor (ly:output-def-lookup
- paper 'verticalequalizationfactor 0.3)))
+ (page-alist (layout->page-init paper))
+ (force-equalization-factor (ly:output-def-lookup
+ paper 'verticalequalizationfactor 0.3)))
(ly:message (_ "Calculating page breaks..."))
(let* ((best-break-node (walk-lines '() '() lines paper-book page-alist))
- (break-nodes (get-path best-break-node '())))
+ (break-nodes (get-path best-break-node '())))
(page-set-property! (car (last-pair break-nodes)) 'is-last #t)
(if #f; (ly:get-option 'verbose)
- (begin
- (display (list
- "\nbreaks: " (map (lambda (node)
- (ly:prob-property (car (page-lines node))
- 'number))
- break-nodes)
- "\nsystems " (map page-lines break-nodes)
- "\npenalties " (map page-penalty break-nodes)
- "\nconfigs " (map page-configuration break-nodes)))))
+ (begin
+ (display (list
+ "\nbreaks: " (map (lambda (node)
+ (ly:prob-property (car (page-lines node))
+ 'number))
+ break-nodes)
+ "\nsystems " (map page-lines break-nodes)
+ "\npenalties " (map page-penalty break-nodes)
+ "\nconfigs " (map page-configuration break-nodes)))))
;; construct page stencils.
(for-each page-stencil break-nodes)
- (post-process-pages paper break-nodes)
break-nodes)))