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"
36 Stencil::Stencil (Box b, SCM func)
43 Stencil::mark_smob () const
48 const char Stencil::type_p_name_[] = "ly:stencil?";
51 Stencil::extent (Axis a) const
57 Stencil::is_empty () const
59 return (scm_is_null (expr_)
64 Stencil::is_empty (Axis a) const
66 return dim_.is_empty (a);
70 Stencil::expr () const
76 Stencil::extent_box () const
82 Stencil::rotate (Real a, Offset off)
84 rotate_degrees (a * 180 / M_PI, off);
88 Rotate this stencil around the point ABSOLUTE_OFF.
92 Stencil::rotate_degrees_absolute (Real a, Offset absolute_off)
94 const Real x = absolute_off[X_AXIS];
95 const Real y = absolute_off[Y_AXIS];
98 * Build scheme expression (processed in stencil-interpret.cc)
100 /* TODO: by hanwenn 2008/09/10 14:38:56:
101 * in effect, this copies the underlying expression. It might be a
102 * little bit nicer to mirror this in the api, ie. make a
104 * and have Stencil::rotate be an abbrev of
108 expr_ = scm_list_n (ly_symbol2scm ("rotate-stencil"),
109 scm_list_2 (scm_from_double (a),
110 scm_cons (scm_from_double (x), scm_from_double (y))),
111 expr_, SCM_UNDEFINED);
114 * Calculate the new bounding box
116 Box shifted_box = extent_box ();
117 shifted_box.translate (-absolute_off);
120 pts.push_back (Offset (shifted_box.x ().at (LEFT), shifted_box.y ().at (DOWN)));
121 pts.push_back (Offset (shifted_box.x ().at (RIGHT), shifted_box.y ().at (DOWN)));
122 pts.push_back (Offset (shifted_box.x ().at (RIGHT), shifted_box.y ().at (UP)));
123 pts.push_back (Offset (shifted_box.x ().at (LEFT), shifted_box.y ().at (UP)));
125 const Offset rot = complex_exp (Offset (0, a * M_PI / 180.0));
127 for (vsize i = 0; i < pts.size (); i++)
128 dim_.add_point (pts[i] * rot + absolute_off);
132 Rotate this stencil around the point RELATIVE_OFF.
134 RELATIVE_OFF is measured in terms of the extent of the stencil, so
135 -1 = LEFT/DOWN edge, 1 = RIGHT/UP edge.
138 Stencil::rotate_degrees (Real a, Offset relative_off)
141 * Calculate the center of rotation
143 const Real x = extent (X_AXIS).linear_combination (relative_off[X_AXIS]);
144 const Real y = extent (Y_AXIS).linear_combination (relative_off[Y_AXIS]);
145 rotate_degrees_absolute (a, Offset (x, y));
149 Stencil::translate (Offset o)
158 || fabs (o[a]) > 1e6)
160 programming_error (String_convert::form_string ("Improbable offset for stencil: %f staff space", o[a])
162 + "Setting to zero.");
164 if (strict_infinity_checking)
165 scm_misc_error (__FUNCTION__, "Improbable offset.", SCM_EOL);
170 if (!scm_is_null (expr_))
171 expr_ = scm_list_n (ly_symbol2scm ("translate-stencil"),
173 expr_, SCM_UNDEFINED);
178 Stencil::translate_axis (Real x, Axis a)
186 Stencil::scale (Real x, Real y)
188 expr_ = scm_list_3 (ly_symbol2scm ("scale-stencil"),
189 scm_list_2 (scm_from_double (x),
190 scm_from_double (y)),
197 Stencil::add_stencil (Stencil const &s)
199 SCM cs = ly_symbol2scm ("combine-stencil");
200 if (scm_is_null (expr_))
202 else if (scm_is_null (s.expr_))
204 else if (scm_is_pair (expr_)
205 && scm_is_eq (cs, scm_car (expr_)))
207 if (scm_is_pair (s.expr_)
208 && scm_is_eq (cs, scm_car (s.expr_)))
209 expr_ = scm_append (scm_list_2 (s.expr_, scm_cdr (expr_)));
211 expr_ = scm_cons2 (cs, s.expr_, scm_cdr (expr_));
215 if (scm_is_pair (s.expr_)
216 && scm_is_eq (cs, scm_car (s.expr_)))
217 expr_ = scm_append (scm_list_2 (s.expr_, scm_list_1 (expr_)));
219 expr_ = scm_list_3 (cs, s.expr_, expr_);
225 Stencil::set_empty (bool e)
229 dim_[X_AXIS].set_empty ();
230 dim_[Y_AXIS].set_empty ();
234 dim_[X_AXIS] = Interval (0, 0);
235 dim_[Y_AXIS] = Interval (0, 0);
240 Stencil::align_to (Axis a, Real x)
245 Interval i (extent (a));
246 translate_axis (-i.linear_combination (x), a);
249 /* See scheme Function. */
251 // Any stencil that is empty in the orthogonal axis is spacing.
252 // Spacing is not subjected to the std::max (0) rule and can thus be
256 Stencil::add_at_edge (Axis a, Direction d, Stencil const &s, Real padding)
258 // Material that is empty in the axis of reference has only limited
259 // usefulness for combining. We still retain as much information as
260 // available since there may be uses like setting page links or
261 // background color or watermarks, and off-axis extents.
269 Interval first_extent = extent (a);
274 // translation does not affect axis-empty extent box.
275 toadd.translate_axis (first_extent[d], a);
280 Interval next_extent = s.extent (a);
282 bool first_is_spacing = is_empty (other_axis (a));
283 bool next_is_spacing = s.is_empty (other_axis (a));
285 Real offset = first_extent[d] - next_extent[-d];
287 if (!(first_is_spacing || next_is_spacing))
289 offset += d * padding;
293 toadd.translate_axis (offset, a);
297 // Stencil::stack is mainly used for assembling lines or columns
298 // of stencils. For the most common case of adding at the right, the
299 // reference point of the added stencil is usually placed at the right
300 // edge of the current one, unless the added stencil has a negative
301 // left extent in which case its left edge is placed at the right edge
302 // of the current one.
304 // Spacing is special in that it is applied without padding. Spacing
305 // at the right edge shifts the right edge accordingly.
307 // For spacing at the left edge, there are several approaches. In
308 // order to get to predictable behavior, we want to have at least a
309 // continuous approach. An obvious idea is to do a "translate" by the
310 // appropriate amount. Doing that while retaining the nominal left
311 // edge seems like the most straightforward way.
314 Stencil::stack (Axis a, Direction d, Stencil const &s, Real padding, Real mindist)
316 // Material that is empty in the axis of reference can't be sensibly
317 // stacked. We just revert to add_at_edge behavior then.
322 toadd.add_stencil (*this);
323 expr_ = toadd.expr ();
324 dim_ = toadd.extent_box ();
328 Interval first_extent = extent (a);
333 toadd.translate_axis (first_extent[d], a);
334 toadd.add_stencil (*this);
335 expr_ = toadd.expr ();
336 dim_ = toadd.extent_box ();
340 Interval next_extent = s.extent (a);
342 // It is somewhat tedious to special-case all spacing, but it turns
343 // out that not doing so makes it astonishingly hard to make the
344 // code do the correct thing.
346 // If first is spacing, we translate second accordingly without
347 // letting this affect its backward edge.
348 if (is_empty (other_axis (a)))
351 Real offset = d * first_extent.delta ();
352 toadd.translate_axis (offset, a);
353 toadd.add_stencil (*this);
354 expr_ = toadd.expr ();
355 dim_ = toadd.extent_box ();
356 dim_[a][-d] = next_extent[-d];
357 dim_[a][d] = next_extent[d] + offset;
361 // If next is spacing, similar action:
362 if (s.is_empty (other_axis (a)))
365 Real offset = first_extent [d];
366 toadd.translate_axis (offset, a);
367 toadd.add_stencil (*this);
368 expr_ = toadd.expr ();
369 dim_ = toadd.extent_box ();
370 dim_[a][-d] = first_extent[-d];
371 dim_[a][d] = first_extent[d] + d * next_extent.delta ();
376 Real offset = first_extent[d];
378 // If the added stencil has a backwardly protruding edge, we make
379 // room for it when combining.
381 if (d * next_extent [-d] < 0)
382 offset -= next_extent [-d];
384 offset += d * padding;
386 if (offset * d < mindist)
387 offset = d * mindist;
390 toadd.translate_axis (offset, a);
391 toadd.add_stencil (*this);
392 expr_ = toadd.expr ();
393 dim_ = toadd.extent_box ();
394 dim_[a][-d] = first_extent [-d];
395 dim_[a][d] = next_extent [d] + offset;
400 Stencil::in_color (Real r, Real g, Real b) const
402 Stencil new_stencil (extent_box (),
403 scm_list_3 (ly_symbol2scm ("color"),
404 scm_list_3 (scm_from_double (r),
406 scm_from_double (b)),
413 Stencil::translated (Offset z) const