2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 1997--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
6 LilyPond is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 LilyPond is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
23 #include "font-metric.hh"
25 #include "string-convert.hh"
35 Stencil::Stencil (Box b, SCM func)
42 Stencil::mark_smob () const
47 const char Stencil::type_p_name_[] = "ly:stencil?";
50 Stencil::extent (Axis a) const
56 Stencil::is_empty () const
58 return (scm_is_null (expr_)
63 Stencil::is_empty (Axis a) const
65 return dim_.is_empty (a);
69 Stencil::expr () const
75 Stencil::extent_box () const
81 Stencil::rotate (Real a, Offset off)
83 rotate_degrees (a * 180 / M_PI, off);
87 Rotate this stencil around the point ABSOLUTE_OFF.
91 Stencil::rotate_degrees_absolute (Real a, Offset absolute_off)
93 const Real x = absolute_off[X_AXIS];
94 const Real y = absolute_off[Y_AXIS];
97 * Build scheme expression (processed in stencil-interpret.cc)
99 /* TODO: by hanwenn 2008/09/10 14:38:56:
100 * in effect, this copies the underlying expression. It might be a
101 * little bit nicer to mirror this in the api, ie. make a
103 * and have Stencil::rotate be an abbrev of
107 expr_ = scm_list_n (ly_symbol2scm ("rotate-stencil"),
108 scm_list_2 (scm_from_double (a),
109 scm_cons (scm_from_double (x), scm_from_double (y))),
110 expr_, SCM_UNDEFINED);
113 * Calculate the new bounding box
115 Box shifted_box = extent_box ();
116 shifted_box.translate (-absolute_off);
119 pts.push_back (Offset (shifted_box.x ().at (LEFT), shifted_box.y ().at (DOWN)));
120 pts.push_back (Offset (shifted_box.x ().at (RIGHT), shifted_box.y ().at (DOWN)));
121 pts.push_back (Offset (shifted_box.x ().at (RIGHT), shifted_box.y ().at (UP)));
122 pts.push_back (Offset (shifted_box.x ().at (LEFT), shifted_box.y ().at (UP)));
124 const Offset rot = complex_exp (Offset (0, a * M_PI / 180.0));
126 for (vsize i = 0; i < pts.size (); i++)
127 dim_.add_point (pts[i] * rot + absolute_off);
131 Rotate this stencil around the point RELATIVE_OFF.
133 RELATIVE_OFF is measured in terms of the extent of the stencil, so
134 -1 = LEFT/DOWN edge, 1 = RIGHT/UP edge.
137 Stencil::rotate_degrees (Real a, Offset relative_off)
140 * Calculate the center of rotation
142 const Real x = extent (X_AXIS).linear_combination (relative_off[X_AXIS]);
143 const Real y = extent (Y_AXIS).linear_combination (relative_off[Y_AXIS]);
144 rotate_degrees_absolute (a, Offset (x, y));
148 Stencil::translate (Offset o)
157 || fabs (o[a]) > 1e6)
159 programming_error (String_convert::form_string ("Improbable offset for stencil: %f staff space", o[a])
161 + "Setting to zero.");
163 if (strict_infinity_checking)
164 scm_misc_error (__FUNCTION__, "Improbable offset.", SCM_EOL);
169 if (!scm_is_null (expr_))
170 expr_ = scm_list_n (ly_symbol2scm ("translate-stencil"),
172 expr_, SCM_UNDEFINED);
177 Stencil::translate_axis (Real x, Axis a)
185 Stencil::scale (Real x, Real y)
187 expr_ = scm_list_3 (ly_symbol2scm ("scale-stencil"),
188 scm_list_2 (scm_from_double (x),
189 scm_from_double (y)),
196 Stencil::add_stencil (Stencil const &s)
198 SCM cs = ly_symbol2scm ("combine-stencil");
199 if (scm_is_null (expr_))
201 else if (scm_is_null (s.expr_))
203 else if (scm_is_pair (expr_)
204 && scm_is_eq (cs, scm_car (expr_)))
206 if (scm_is_pair (s.expr_)
207 && scm_is_eq (cs, scm_car (s.expr_)))
208 expr_ = scm_append (scm_list_2 (s.expr_, scm_cdr (expr_)));
210 expr_ = scm_cons2 (cs, s.expr_, scm_cdr (expr_));
214 if (scm_is_pair (s.expr_)
215 && scm_is_eq (cs, scm_car (s.expr_)))
216 expr_ = scm_append (scm_list_2 (s.expr_, scm_list_1 (expr_)));
218 expr_ = scm_list_3 (cs, s.expr_, expr_);
224 Stencil::set_empty (bool e)
228 dim_[X_AXIS].set_empty ();
229 dim_[Y_AXIS].set_empty ();
233 dim_[X_AXIS] = Interval (0, 0);
234 dim_[Y_AXIS] = Interval (0, 0);
239 Stencil::align_to (Axis a, Real x)
244 Interval i (extent (a));
245 translate_axis (-i.linear_combination (x), a);
248 /* See scheme Function. */
250 // Any stencil that is empty in the orthogonal axis is spacing.
251 // Spacing is not subjected to the max (0) rule and can thus be
255 Stencil::add_at_edge (Axis a, Direction d, Stencil const &s, Real padding)
257 // Material that is empty in the axis of reference has only limited
258 // usefulness for combining. We still retain as much information as
259 // available since there may be uses like setting page links or
260 // background color or watermarks, and off-axis extents.
268 Interval first_extent = extent (a);
273 // translation does not affect axis-empty extent box.
274 toadd.translate_axis (first_extent[d], a);
279 Interval next_extent = s.extent (a);
281 bool first_is_spacing = is_empty (other_axis (a));
282 bool next_is_spacing = s.is_empty (other_axis (a));
284 Real offset = first_extent[d] - next_extent[-d];
286 if (!(first_is_spacing || next_is_spacing))
288 offset += d * padding;
292 toadd.translate_axis (offset, a);
296 // Stencil::stack is mainly used for assembling lines or columns
297 // of stencils. For the most common case of adding at the right, the
298 // reference point of the added stencil is usually placed at the right
299 // edge of the current one, unless the added stencil has a negative
300 // left extent in which case its left edge is placed at the right edge
301 // of the current one.
303 // Spacing is special in that it is applied without padding. Spacing
304 // at the right edge shifts the right edge accordingly.
306 // For spacing at the left edge, there are several approaches. In
307 // order to get to predictable behavior, we want to have at least a
308 // continuous approach. An obvious idea is to do a "translate" by the
309 // appropriate amount. Doing that while retaining the nominal left
310 // edge seems like the most straightforward way.
313 Stencil::stack (Axis a, Direction d, Stencil const &s, Real padding, Real mindist)
315 // Material that is empty in the axis of reference can't be sensibly
316 // stacked. We just revert to add_at_edge behavior then.
321 toadd.add_stencil (*this);
322 expr_ = toadd.expr ();
323 dim_ = toadd.extent_box ();
327 Interval first_extent = extent (a);
332 toadd.translate_axis (first_extent[d], a);
333 toadd.add_stencil (*this);
334 expr_ = toadd.expr ();
335 dim_ = toadd.extent_box ();
339 Interval next_extent = s.extent (a);
341 // It is somewhat tedious to special-case all spacing, but it turns
342 // out that not doing so makes it astonishingly hard to make the
343 // code do the correct thing.
345 // If first is spacing, we translate second accordingly without
346 // letting this affect its backward edge.
347 if (is_empty (other_axis (a)))
350 Real offset = d * first_extent.delta ();
351 toadd.translate_axis (offset, a);
352 toadd.add_stencil (*this);
353 expr_ = toadd.expr ();
354 dim_ = toadd.extent_box ();
355 dim_[a][-d] = next_extent[-d];
356 dim_[a][d] = next_extent[d] + offset;
360 // If next is spacing, similar action:
361 if (s.is_empty (other_axis (a)))
364 Real offset = first_extent [d];
365 toadd.translate_axis (offset, a);
366 toadd.add_stencil (*this);
367 expr_ = toadd.expr ();
368 dim_ = toadd.extent_box ();
369 dim_[a][-d] = first_extent[-d];
370 dim_[a][d] = first_extent[d] + d * next_extent.delta ();
375 Real offset = first_extent[d];
377 // If the added stencil has a backwardly protruding edge, we make
378 // room for it when combining.
380 if (d * next_extent [-d] < 0)
381 offset -= next_extent [-d];
383 offset += d * padding;
385 if (offset * d < mindist)
386 offset = d * mindist;
389 toadd.translate_axis (offset, a);
390 toadd.add_stencil (*this);
391 expr_ = toadd.expr ();
392 dim_ = toadd.extent_box ();
393 dim_[a][-d] = first_extent [-d];
394 dim_[a][d] = next_extent [d] + offset;
399 Stencil::in_color (Real r, Real g, Real b) const
401 Stencil new_stencil (extent_box (),
402 scm_list_3 (ly_symbol2scm ("color"),
403 scm_list_3 (scm_from_double (r),
405 scm_from_double (b)),
412 Stencil::translated (Offset z) const