-;;;; flag-styles.scm
+;;;; This file is part of LilyPond, the GNU music typesetter.
;;;;
-;;;; source file of the GNU LilyPOnd music typesetter
+;;;; Copyright (C) 2008--2011 Reinhold Kainhofer <reinhold@kainhofer.com>
;;;;
+;;;; 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/>.
+
;;;; This file implements different flag styles in Scheme / GUILE, most
;;;; notably the old-straight-flag and the modern-straight-flag styles.
-;;;;
(define-public (no-flag stem-grob)
- "No flag: Simply return empty stencil"
+ "No flag: Simply return empty stencil."
empty-stencil)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-(define-public (add-stroke-straight stencil stem-grob dir log stroke-style offset length thickness stroke-thickness)
+(define-public (add-stroke-straight stencil stem-grob dir log stroke-style
+ offset length thickness stroke-thickness)
"Add the stroke for acciaccatura to the given flag stencil.
- The stroke starts for up-flags at upper-end-of-flag+(0,length/2) and
- ends at (0, vertical-center-of-flag-end) - (flag-x-width/2, flag-x-width + flag-thickness).
- Here length is the whole length, while flag-x-width is just the
- x-extent and thus depends on the angle! Other combinations don't look as
- good... For down-stems the y-coordinates are simply mirrored."
+The stroke starts for up-flags at `upper-end-of-flag + (0,length/2)'
+and ends at `(0, vertical-center-of-flag-end) -
+(flag-x-width/2, flag-x-width + flag-thickness)'. Here `length' is the
+whole length, while `flag-x-width' is just the x-extent and thus depends on
+the angle! Other combinations don't look as good.
+
+For down-stems the y-coordinates are simply mirrored."
(let* ((start (offset-add offset (cons 0 (* (/ length 2) dir))))
- (end (offset-add (cons 0 (cdr offset))
+ (end (offset-add (cons 0 (cdr offset))
(cons (- (/ (car offset) 2)) (* (- (+ thickness (car offset))) dir))))
(stroke (make-line-stencil stroke-thickness (car start) (cdr start) (car end) (cdr end))))
(ly:stencil-add stencil stroke)))
-(define PI-OVER-180 (/ (atan 1 1) 45))
-(define (degrees->radians angle-degrees)
- "Convert the given angle from degrees to radians"
- (* angle-degrees PI-OVER-180))
-
-(define (polar->rectangular radius angle-in-degrees)
- "Convert polar coordinate @code{radius} and @code{angle-in-degrees}
- to (x-length . y-length)"
- (let* ((complex (make-polar
- radius
- (degrees->radians angle-in-degrees))))
- (cons
- (real-part complex)
- (imag-part complex))))
-
(define (buildflag flag-stencil remain curr-stencil spacing)
"Internal function to recursively create a stencil with @code{remain} flags
from the single-flag stencil curr-stencil, which is already translated to
flag-stencil))
(define-public (straight-flag flag-thickness flag-spacing
- upflag-angle upflag-length
- downflag-angle downflag-length)
- "Create a stencil for a straight flag.
- flag-thickness, -spacing are given in staff spaces,
- *flag-angle is given in degree, *flag-length is given in staff spaces.
- All lengths will be scaled according to the font size of the note."
+ upflag-angle upflag-length
+ downflag-angle downflag-length)
+ "Create a stencil for a straight flag. @var{flag-thickness} and
+@var{flag-spacing} are given in staff spaces, @var{upflag-angle} and
+@var{downflag-angle} are given in degrees, and @var{upflag-length} and
+@var{downflag-length} are given in staff spaces.
+
+All lengths are scaled according to the font size of the note."
+
(lambda (stem-grob)
(let* ((log (ly:grob-property stem-grob 'duration-log))
(dir (ly:grob-property stem-grob 'direction))
(define-public (modern-straight-flag stem-grob)
"Modern straight flag style (for composers like Stockhausen, Boulez, etc.).
- The angles are 18 and 22 degrees and thus smaller than for the ancient style
- of Bach etc."
+The angles are 18 and 22 degrees and thus smaller than for the ancient style
+of Bach, etc."
((straight-flag 0.55 1 -18 1.1 22 1.2) stem-grob))
(define-public (old-straight-flag stem-grob)
- "Old straight flag style (for composers like Bach). The angles of the flags
- are both 45 degrees."
+ "Old straight flag style (for composers like Bach). The angles of the
+flags are both 45 degrees."
((straight-flag 0.55 1 -45 1.2 45 1.4) stem-grob))
(define-public (add-stroke-glyph stencil stem-grob dir stroke-style flag-style)
"Load and add a stroke (represented by a glyph in the font) to the given
- flag stencil"
+flag stencil."
(if (not (string? stroke-style))
stencil
; Otherwise: look up the stroke glyph and combine it with the flag
(define-public (retrieve-glyph-flag flag-style dir dir-modifier stem-grob)
- "Load the correct flag glyph from the font"
+ "Load the correct flag glyph from the font."
(let* ((log (ly:grob-property stem-grob 'duration-log))
(font (ly:grob-default-font stem-grob))
(font-char (string-append "flags." flag-style dir dir-modifier (number->string log)))
(define-public (create-glyph-flag flag-style dir-modifier stem-grob)
- "Create a flag stencil by looking up the glyph from the font"
+ "Create a flag stencil by looking up the glyph from the font."
(let* ((dir (if (eqv? (ly:grob-property stem-grob 'direction) UP) "u" "d"))
(flag (retrieve-glyph-flag flag-style dir dir-modifier stem-grob))
(stroke-style (ly:grob-property stem-grob 'stroke-style)))
(define-public (mensural-flag stem-grob)
"Mensural flags: Create the flag stencil by loading the glyph from the font.
- Flags are always aligned with staff lines, so we need to check the end point
- of the stem: For stems ending on staff lines, use different flags than for
- notes between staff lines. The idea is that flags are always vertically
- aligned with the staff lines, regardless of whether the note head is on a
- staff line or between two staff lines. In other words, the inner end of
- a flag always touches a staff line."
+Flags are always aligned with staff lines, so we need to check the end point
+of the stem: For stems ending on staff lines, use different flags than for
+notes between staff lines. The idea is that flags are always vertically
+aligned with the staff lines, regardless of whether the note head is on a
+staff line or between two staff lines. In other words, the inner end of
+a flag always touches a staff line."
(let* ((adjust #t)
(stem-end (inexact->exact (round (ly:grob-property stem-grob 'stem-end-position))))
(define-public ((glyph-flag flag-style) stem-grob)
- "Simulates the default way of generating flags: look up glyphs
- flags.style[ud][1234] from the feta font and use it for the flag stencil."
+ "Simulatesthe default way of generating flags: Look up glyphs
+@code{flags.style[ud][1234]} from the feta font and use it for the flag
+stencil."
(create-glyph-flag flag-style "" stem-grob))
(define-public (normal-flag stem-grob)
- "Create a default flag"
+ "Create a default flag."
(create-glyph-flag "" "" stem-grob))
(define-public (default-flag stem-grob)
- "Create a flag stencil for the stem. Its style will be derived from the
- @code{'flag-style} Stem property. By default, @code{lilypond} uses a
- C++ Function (which is slightly faster) to do exactly the same as this
- function. However, if one wants to modify the default flags, this function
- can be used to obtain the default flag stencil, which can then be modified
- at will. The correct way to do this is:
+ "Create a flag stencil for the stem. Its style will be derived from the
+@code{'flag-style} Stem property. By default, @code{lilypond} uses a
+C++ Function (which is slightly faster) to do exactly the same as this
+function. However, if one wants to modify the default flags, this function
+can be used to obtain the default flag stencil, which can then be modified
+at will. The correct way to do this is:
+
@example
\\override Stem #'flag = #default-flag
\\override Stem #'flag-style = #'mensural