Spaces:
Sleeping
Sleeping
| ;;;; This file is part of LilyPond, the GNU music typesetter. | |
| ;;;; | |
| ;;;; Copyright (C) 2006--2020 Han-Wen Nienhuys <[email protected]> | |
| ;;;; | |
| ;;;; LilyPond is free software: you can redistribute it and/or modify | |
| ;;;; it under the terms of the GNU General Public License as published by | |
| ;;;; the Free Software Foundation, either version 3 of the License, or | |
| ;;;; (at your option) any later version. | |
| ;;;; | |
| ;;;; LilyPond is distributed in the hope that it will be useful, | |
| ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| ;;;; GNU General Public License for more details. | |
| ;;;; | |
| ;;;; You should have received a copy of the GNU General Public License | |
| ;;;; along with LilyPond. If not, see <http://www.gnu.org/licenses/>. | |
| (define-module (scm clip-region)) | |
| (use-modules (lily)) | |
| ;; | |
| ;; the total of this will be | |
| ;; O(#systems * #regions) | |
| ;; | |
| ;; we can actually do better by sorting the regions as well, | |
| ;; but let's leave that for future extensions. | |
| ;; | |
| (define-public (system-clipped-x-extent system-grob clip-region) | |
| "Return the X-extent of @var{system-grob} when clipped with | |
| @var{clip-region}, a pair @var{start}, @var{end}, both rhythmic | |
| locations. Return @code{#f} if not appropriate." | |
| (let* | |
| ((region-start (car clip-region)) | |
| (columns (ly:grob-object system-grob 'columns)) | |
| (region-end (cdr clip-region)) | |
| (found-grace-end #f) | |
| (candidate-columns | |
| (filter | |
| (lambda (j) | |
| (let* | |
| ((column (ly:grob-array-ref columns j)) | |
| (loc (ly:grob-property column 'rhythmic-location)) | |
| (grace-less (make-graceless-rhythmic-location loc)) | |
| ) | |
| (and (rhythmic-location? loc) | |
| (rhythmic-location<=? region-start loc) | |
| (or (rhythmic-location<? grace-less region-end) | |
| (and (rhythmic-location=? grace-less region-end) | |
| (eq? #t (ly:grob-property column 'non-musical)) | |
| ))) | |
| )) | |
| (iota (ly:grob-array-length columns)))) | |
| (column-range | |
| (if (>= 1 (length candidate-columns)) | |
| #f | |
| (cons (car candidate-columns) | |
| (car (last-pair candidate-columns))))) | |
| (clipped-x-interval | |
| (if column-range | |
| (cons | |
| (interval-start | |
| (ly:grob-robust-relative-extent | |
| (if (= 0 (car column-range)) | |
| system-grob | |
| (ly:grob-array-ref columns (car column-range))) | |
| system-grob X)) | |
| (interval-end | |
| (ly:grob-robust-relative-extent | |
| (if (= (1- (ly:grob-array-length columns)) (cdr column-range)) | |
| system-grob | |
| (ly:grob-array-ref columns (cdr column-range))) | |
| system-grob X))) | |
| #f | |
| ))) | |
| clipped-x-interval)) | |