+% Feta (not the Font-En-Tja) music font -- global parameters for both feta and parmesan fonts
+% This file is part of LilyPond, the GNU music typesetter.
+%
+% Copyright (C) 1997--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
+%
+% The LilyPond font 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, or under the SIL Open Font License.
+%
+% 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/>.
+
+stafflines := 5;
+
+%
+% The design size of a staff should really be the
+% staff_space, but we use staffsize for historical reasons.
+%
+
+staff_space# := staffsize# / (stafflines - 1);
+staff_space_rounded# := staff_space#;
+
+
+%
+% Measuring on pocket scores turns out: stafflinethickness is
+% largely independent on staff size, and generally about 0.5 pt.
+%
+% By request of WL, we tune down the blackness a little
+% for increased contrast with beams.
+%
-stafflines = 5;
+%% !! synchronize with paper.scm
-staff_space#:=staffsize#/(stafflines-1);
+save fixed_line_thickness, variable_line_factor;
+fixed_line_thickness + variable_line_factor * 5 pt# = 0.50 pt#;
+fixed_line_thickness + variable_line_factor * 4.125 pt# = 0.47 pt#;
-% URG!
-font_x_height staff_space# ;
+stafflinethickness# := fixed_line_thickness
+ + variable_line_factor * staff_space#;
+stafflinethickness_rounded# := stafflinethickness#;
%
-% [D.K.Roush & J.S.Gourlay] say this should be 0.072
-% We know better
-% generally, the "blackness" of most chars depends on this.
+% The following tunes the general blackness of the glyphs.
%
-stafflinethickness#:=0.1 staff_space#;
-stemthickness# := stafflinethickness#;
+linethickness# := stafflinethickness#; %% 0.5 pt#;
+linethickness_rounded# := linethickness#;
+
+%
+% bigger puff_up_factor, relatively thicker stafflines.
+%
+% 20 pt = puff_up_factor 0
+% 10 pt = puff_up_factor 1
+%
+
+puff_up_factor = (linethickness# - 0.1 staff_space#) / (0.1 staff_space#);
+
+
+stemthickness# := 1.3 stafflinethickness#;
+stemthickness_rounded# := stemthickness#;
ledgerlinethickness# := 2 stafflinethickness#;
+ledgerlinethickness_rounded# := ledgerlinethickness#;
+
+define_pixels (staff_space, stemthickness, stafflinethickness,
+ ledgerlinethickness, linethickness);
+define_whole_pixels (staff_space_rounded);
+define_whole_blacker_pixels (stemthickness_rounded);
+define_whole_vertical_blacker_pixels (stafflinethickness_rounded,
+ ledgerlinethickness_rounded,
+ linethickness_rounded);
+
+if ledgerlinethickness_rounded > 2 stafflinethickness_rounded:
+ ledgerlinethickness_rounded := 2 stafflinethickness_rounded;
+fi;
+
+%
+% Because of the engraving/stamping process, no traditional
+% characters have sharp edges and corners.
+% The following variable controls the amount of `roundness'.
+%
+% This is not a meta variable: it is related to absolute sizes.
+%
+% FIXME: According to [Wanske], only outside corners should be round
+% I don't think we do this anywhere -- jcn
+%
+
+blot_diameter# = .40 pt#;
+if (blot_diameter# * hppp) < 1:
+ blot_diameter# := 1 / hppp;
+fi
+if (blot_diameter# * vppp) < 1:
+ blot_diameter# := 1 / vppp;
+fi
+
+define_pixels (blot_diameter);
+
+
+%
+% symmetry
+% --------
+%
+% Some glyphs have to be positioned exactly between stafflines (clefs,
+% note heads). This needs some care at lower resolutions.
+%
+% Most glyphs use the staffline thickness and the space between two
+% staff lines as the fundamental parameters. The latter is the distance
+% between the middle of one staff line to the middle of the next. To
+% say it differently, the value `staff_space' is the sum of one staff line
+% thickness and the whitespace between two adjacent staff lines.
+%
+% Normally, feta's vertical origin for glyphs is either the middle
+% between two staff lines or the middle of a staff line. For example, the
+% lower edge of the central staff line is at the vertical position
+% `-<staffline thickness> / 2', and the upper edge at
+% `<staffline thickness> / 2'. Here we need a value rounded to an integer
+% (the feta code uses `stafflinethickness_rounded' for that purpose).
+%
+% If we have an odd number of pixels as the staffline thickness, Metafont
+% rounds `-stafflinethickness_rounded / 2' towards zero and
+% `stafflinethickness_rounded / 2' towards infinity. Example: `round -1.5'
+% yields -1, `round 1.5' yields 2. The whitespace between staff lines is
+% handled similarly. If we assume that stafflinethickness_rounded is odd,
+% we have the following cases:
+%
+% o The glyph is centered between three stafflines or five stafflines
+% (clef, `c' meter). We have this:
+%
+% ___________ a
+% ___________ 1
+% ___________ a
+%
+% whitespace
+%
+% ___________ a
+% ...... ___________ 1 .................. x axis
+% ___________ a
+%
+% whitespace
+%
+% ___________ a
+% ___________ 1
+% ___________ a
+%
+% As can be seen, we get symmetry if we split staff lines into two
+% equal parts `a' and a pixel line with thickness 1. Consequently, we
+% use the following algorithm:
+%
+% . Decrease the height `h' by 1 temporarily.
+%
+% . Compute the path for the upper half of the glyph.
+%
+% . Mirror the path at the x axis.
+%
+% . Shift the upper half one pixel up and connect it with the lower path.
+%
+% . Restore height and decrease `d' by 1.
+%
+% o The glyph is centered between two or four staff lines, and the origin is
+% the middle of the whitespace. Assuming that the whitespace consists of
+% an odd number of pixels, we have this:
+%
+% -----------
+% b
+% 1
+% b
+% ___________
+% b
+% .................. 1 ................. x axis
+% b
+% ___________
+% b
+% 1
+% b
+% ___________
+%
+% For symmetrical glyphs, this leads to a similar algorithm as above.
+% Glyphs which can't be constructed from an upper and lower part need
+% to be handled differently, namely to shift up the vertical center by
+% half a pixel:
+%
+% ___________
+% b
+%
+% 0.5
+% .................. 0.5 ................ x axis
+%
+% b
+% ___________
+%
+
+feta_eps := 0;
+feta_shift := 0;
+feta_space_shift := 0;
+
+% Use this for paths with a slant of 45 degrees to assure that
+% the middle point of a penpos gets covered.
+pair feta_offset;
+feta_offset := (0, 0);
+
+if known miterlimit:
+ pickup nullpen;
+else:
+ feta_eps := eps;
+
+ if odd stafflinethickness_rounded:
+ feta_shift := 1;
+ fi;
+
+ if odd (staff_space_rounded - stafflinethickness_rounded):
+ feta_space_shift := 1;
+ fi;
+
+ feta_offset := (0.5, 0.5);
+
+ pickup pencircle scaled 1;
+fi;
+
+feta_fillpen := savepen;
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Notehead width and height are defined here.
+%
+%
+% Slope of slash. From scm/grob-description.scm. How to auto-copy?
+slash_slope := 1.7;
-define_pixels(staff_space, stemthickness);
-define_pixels(stafflinethickness,ledgerlinethickness);
+% Thickness of slash lines. Quarter notes get 1.5slt width.
+slash_thick# := 2/3 * 0.48 staff_space#;
%
% Hand-engraved music often has balls extending above and below
% the lines. If you like that, modify overdone heads (unit:
-% stafflinethickness)
+% stafflinethickness).
%
-numeric overdone_heads;
-overdone_heads = 0.0;
+%% FIXME
+% There is a problem with noteheads slightly extending beyond the staff
+% lines. This is due to the fact that staff_space + stafflinethickness
+% is sometimes an odd number, so the nothead height and depth are not
+% integers. Then, when the font is converted to an outline font, the
+% system rounds up the 0.5 left over from dividing the notehead height
+% in two, and the notehead extends slightly beyond the staff line.
+% In order to resolve this problem, we use overdone_heads to slightly
+% reduce the notehead height. Empirically, we have determined that
+% reducing by 10% of stafflinethickness solves the problem.
-%
-% Because of the engraving/stamping process, no traditional
-% characters have sharp edges and corners
-% The following variable controls the amount of "roundness"
+overdone_heads = -0.1;
+noteheight# := staff_space# + (1 + overdone_heads) * stafflinethickness#;
+
+define_pixels (slash_thick);
+define_whole_vertical_pixels (noteheight);
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
-% this is not a meta variable: it is related to absolute sizes.
+% This is used to draw all elliptical notes; it also sets
+% black_notehead_width, so it should be called in any file that
+% needs the value of black_notehead_width.
%
-% According to [Wanske], only outside corners should be round
+% SLANT moves both extrema on the long axis (by SLANT * ELLIPTICITY,
+% so SLANT = -1, puts the extreme on the long axis next to the short
+% axis one).
%
-numeric blot_diameter;
-blot_diameter# = .4pt#;
-define_pixels(blot_diameter);
+
+def draw_outside_ellipse (expr ellipticity, tilt, superness, slant) =
+ save attachment_y;
+ save pat;
+ path pat;
+
+ pat := superellipse ((ellipticity, 0), (-slant * ellipticity, 1.0),
+ (-ellipticity, 0), (slant * ellipticity, -1.0),
+ superness);
+ pat := pat rotated tilt;
+
+ save top_point, right_point;
+ pair top_point, right_point;
+
+ top_point := directionpoint left of pat;
+ right_point := directionpoint up of pat;
+
+ save scaling, width;
+
+ scaling# := noteheight# / (2 ypart (top_point));
+ width# := 2 xpart (right_point) * scaling#;
+ define_pixels (scaling, width);
+ set_char_box (0, width#, noteheight# / 2, noteheight# / 2);
+
+ d := d - feta_space_shift;
+
+ % attachment Y
+ charwy := ypart (right_point) * scaling#;
+ charwx := width#;
+
+ pat := pat scaled scaling shifted (w / 2, .5 (h - d));
+
+ width := hround width;
+
+ if test_outlines = 1:
+ draw pat;
+ else:
+ fill pat;
+ fi;
+enddef;
+
+
+def draw_quarter_path =
+ draw_outside_ellipse (1.49 - puff_up_factor / 3.0, 31, 0.707, 0);
+enddef;
+
+test_outlines := 0;
+draw_quarter_path;
+black_notehead_width# := charwd;
+
+define_pixels (slash_thick);
+define_whole_vertical_pixels (noteheight);
+
+
projects / lilypond.git / blobdiff