CVSROOT: /cvsroot/lilypond Module name: lilypond Branch: lilypond_2_6 Changes by: Han-Wen Nienhuys <[EMAIL PROTECTED]> 05/08/04 15:57:47
Modified files: . : ChangeLog lily : beam.cc Log message: (shift_region_to_valid): prevent division by zero. Fixes beams across line breaks with 1 stem after the break. CVSWeb URLs: http://savannah.gnu.org/cgi-bin/viewcvs/lilypond/lilypond/ChangeLog.diff?only_with_tag=lilypond_2_6&tr1=1.3836.2.17&tr2=1.3836.2.18&r1=text&r2=text http://savannah.gnu.org/cgi-bin/viewcvs/lilypond/lilypond/lily/beam.cc.diff?only_with_tag=lilypond_2_6&tr1=1.302&tr2=1.302.2.1&r1=text&r2=text Patches: Index: lilypond/ChangeLog diff -u lilypond/ChangeLog:1.3836.2.17 lilypond/ChangeLog:1.3836.2.18 --- lilypond/ChangeLog:1.3836.2.17 Thu Aug 4 11:11:29 2005 +++ lilypond/ChangeLog Thu Aug 4 15:57:47 2005 @@ -1,5 +1,10 @@ 2005-08-04 Han-Wen Nienhuys <[EMAIL PROTECTED]> - + + * lily/beam.cc (shift_region_to_valid): prevent division by + zero. Fixes beams across line breaks with 1 stem after the break. + + * VERSION: release 2.6.3 + * lily/auto-beam-engraver.cc (derived_mark): new method. Yes. We have to protect even those unlikely-to-be-corrupted data members. Index: lilypond/lily/beam.cc diff -u /dev/null lilypond/lily/beam.cc:1.302.2.1 --- /dev/null Thu Aug 4 15:57:48 2005 +++ lilypond/lily/beam.cc Thu Aug 4 15:57:47 2005 @@ -0,0 +1,1413 @@ +/* + beam.cc -- implement Beam + + source file of the GNU LilyPond music typesetter + + (c) 1997--2005 Han-Wen Nienhuys <[EMAIL PROTECTED]> + Jan Nieuwenhuizen <[EMAIL PROTECTED]> +*/ + +/* + TODO: + + - Determine auto knees based on positions if it's set by the user. + + - the code is littered with * and / staff_space calls for + #'positions. Consider moving to real-world coordinates? + + Problematic issue is user tweaks (user tweaks are in staff-coordinates.) + + Notes: + + - Stems run to the Y-center of the beam. + + - beam_translation is the offset between Y centers of the beam. +*/ + +#include <math.h> // tanh. + +#include "beam.hh" +#include "interval-set.hh" +#include "directional-element-interface.hh" +#include "beaming.hh" +#include "misc.hh" +#include "least-squares.hh" +#include "stem.hh" +#include "output-def.hh" +#include "lookup.hh" +#include "group-interface.hh" +#include "staff-symbol-referencer.hh" +#include "item.hh" +#include "spanner.hh" +#include "warn.hh" + +#if DEBUG_QUANTING +#include "text-interface.hh" // debug output. +#include "font-interface.hh" // debug output. +#endif + +void +Beam::add_stem (Grob *me, Grob *s) +{ + Pointer_group_interface::add_grob (me, ly_symbol2scm ("stems"), s); + + s->add_dependency (me); + + assert (!Stem::get_beam (s)); + s->set_property ("beam", me->self_scm ()); + + add_bound_item (dynamic_cast<Spanner *> (me), dynamic_cast<Item *> (s)); +} + +Real +Beam::get_thickness (Grob *me) +{ + return robust_scm2double (me->get_property ("thickness"), 0) + * Staff_symbol_referencer::staff_space (me); +} + +/* Return the translation between 2 adjoining beams. */ +Real +Beam::get_beam_translation (Grob *me) +{ + SCM func = me->get_property ("space-function"); + + if (ly_c_procedure_p (func)) + { + SCM s = scm_call_2 (func, me->self_scm (), scm_int2num (get_beam_count (me))); + return scm_to_double (s); + } + else + { + return 0.81; + } +} + +/* Maximum beam_count. */ +int +Beam::get_beam_count (Grob *me) +{ + int m = 0; + for (SCM s = me->get_property ("stems"); scm_is_pair (s); s = scm_cdr (s)) + { + Grob *stem = unsmob_grob (scm_car (s)); + m = max (m, (Stem::beam_multiplicity (stem).length () + 1)); + } + return m; +} + +/* + Space return space between beams. +*/ +MAKE_SCHEME_CALLBACK (Beam, space_function, 2); +SCM +Beam::space_function (SCM smob, SCM beam_count) +{ + Grob *me = unsmob_grob (smob); + + Real staff_space = Staff_symbol_referencer::staff_space (me); + Real line = Staff_symbol_referencer::line_thickness (me); + Real thickness = get_thickness (me); + + Real beam_translation = scm_to_int (beam_count) < 4 + ? (2 * staff_space + line - thickness) / 2.0 + : (3 * staff_space + line - thickness) / 3.0; + + return scm_make_real (beam_translation); +} + +/* After pre-processing all directions should be set. + Several post-processing routines (stem, slur, script) need stem/beam + direction. + Currenly, this means that beam has set all stem's directions. + [Alternatively, stems could set its own directions, according to + their beam, during 'final-pre-processing'.] */ +MAKE_SCHEME_CALLBACK (Beam, before_line_breaking, 1); +SCM +Beam::before_line_breaking (SCM smob) +{ + Grob *me = unsmob_grob (smob); + + /* Beams with less than 2 two stems don't make much sense, but could happen + when you do + + [r8 c8 r8]. + + For a beam that only has one stem, we try to do some disappearance magic: + we revert the flag, and move on to The Eternal Engraving Fields. */ + + int count = visible_stem_count (me); + if (count < 2) + { + SCM stems = me->get_property ("stems"); + if (scm_ilength (stems) == 1) + { + me->warning (_ ("removing beam with less than two stems")); + + unsmob_grob (scm_car (stems))->set_property ("beam", SCM_EOL); + me->suicide (); + + return SCM_UNSPECIFIED; + } + else if (scm_ilength (stems) == 0) + { + me->suicide (); + return SCM_UNSPECIFIED; + } + } + if (count >= 1) + { + Direction d = get_default_dir (me); + + consider_auto_knees (me); + set_stem_directions (me, d); + + connect_beams (me); + + set_stem_shorten (me); + } + + return SCM_EOL; +} + +/* We want a maximal number of shared beams, but if there is choice, we + * take the one that is closest to the end of the stem. This is for + * situations like + * + * x + * | + * | + * |===| + * |= + * | + * x + */ +int +position_with_maximal_common_beams (SCM left_beaming, SCM right_beaming, + Direction left_dir, + Direction right_dir) +{ + Slice lslice = int_list_to_slice (scm_cdr (left_beaming)); + + int best_count = 0; + int best_start = 0; + for (int i = lslice[-left_dir]; + (i - lslice[left_dir]) * left_dir <= 0; i += left_dir) + { + int count = 0; + for (SCM s = scm_car (right_beaming); scm_is_pair (s); s = scm_cdr (s)) + { + int k = -right_dir * scm_to_int (scm_car (s)) + i; + if (scm_c_memq (scm_int2num (k), left_beaming) != SCM_BOOL_F) + count++; + } + + if (count >= best_count) + { + best_count = count; + best_start = i; + } + } + + return best_start; +} + +void +Beam::connect_beams (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + Slice last_int; + last_int.set_empty (); + SCM last_beaming = SCM_EOL; + Direction last_dir = CENTER; + for (int i = 0; i < stems.size (); i++) + { + Grob *this_stem = stems[i]; + SCM this_beaming = this_stem->get_property ("beaming"); + + Direction this_dir = get_grob_direction (this_stem); + if (scm_is_pair (last_beaming) && scm_is_pair (this_beaming)) + { + int start_point = position_with_maximal_common_beams + (last_beaming, this_beaming, + last_dir, this_dir); + + Direction d = LEFT; + Slice new_slice; + do + { + if (d == RIGHT && i == stems.size () - 1) + continue; + + new_slice.set_empty (); + SCM s = index_get_cell (this_beaming, d); + for (; scm_is_pair (s); s = scm_cdr (s)) + { + int new_beam_pos + = start_point - this_dir * scm_to_int (scm_car (s)); + + new_slice.add_point (new_beam_pos); + scm_set_car_x (s, scm_int2num (new_beam_pos)); + } + } + while (flip (&d) != LEFT); + + if (!new_slice.is_empty ()) + last_int = new_slice; + } + else + { + scm_set_car_x (this_beaming, SCM_EOL); + SCM s = scm_cdr (this_beaming); + for (; scm_is_pair (s); s = scm_cdr (s)) + { + int np = -this_dir * scm_to_int (scm_car (s)); + scm_set_car_x (s, scm_int2num (np)); + last_int.add_point (np); + } + } + + if (i == stems.size () -1) + { + scm_set_cdr_x (this_beaming, SCM_EOL); + } + + if (scm_ilength (scm_cdr (this_beaming)) > 0) + { + last_beaming = this_beaming; + last_dir = this_dir; + } + } +} + +/* + TODO: should not make beams per stem, but per Y-level. +*/ +MAKE_SCHEME_CALLBACK (Beam, print, 1); +SCM +Beam::print (SCM grob) +{ + Spanner *me = unsmob_spanner (grob); + position_beam (me); + + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + Grob *xcommon = common_refpoint_of_array (stems, me, X_AXIS); + + xcommon = me->get_bound (LEFT)->common_refpoint (xcommon, X_AXIS); + xcommon = me->get_bound (RIGHT)->common_refpoint (xcommon, X_AXIS); + + Real x0, dx; + if (visible_stem_count (me)) + { + // ugh -> use commonx + x0 = first_visible_stem (me)->relative_coordinate (xcommon, X_AXIS); + dx = last_visible_stem (me)->relative_coordinate (xcommon, X_AXIS) - x0; + } + else + { + x0 = stems[0]->relative_coordinate (xcommon, X_AXIS); + dx = stems.top ()->relative_coordinate (xcommon, X_AXIS) - x0; + } + + SCM posns = me->get_property ("positions"); + Drul_array<Real> pos; + if (!is_number_pair (posns)) + { + programming_error ("no beam positions?"); + pos = Interval (0, 0); + } + else + pos = ly_scm2realdrul (posns); + + scale_drul (&pos, Staff_symbol_referencer::staff_space (me)); + + Real dy = pos[RIGHT] - pos[LEFT]; + Real slope = (dy && dx) ? dy / dx : 0; + + Real thick = get_thickness (me); + Real bdy = get_beam_translation (me); + + SCM last_beaming = SCM_EOL; + Real last_xposn = -1; + Real last_stem_width = -1; + + Real gap_length = robust_scm2double (me->get_property ("gap"), 0.0); + + Stencil the_beam; + Real lt = me->get_layout ()->get_dimension (ly_symbol2scm ("linethickness")); + + for (int i = 0; i <= stems.size (); i++) + { + Grob *st = (i < stems.size ()) ? stems[i] : 0; + + SCM this_beaming = st ? st->get_property ("beaming") : SCM_EOL; + Real xposn = st ? st->relative_coordinate (xcommon, X_AXIS) : 0.0; + Real stem_width = st ? robust_scm2double (st->get_property ("thickness"), 1.0) * lt : 0; + Direction stem_dir = st ? to_dir (st->get_property ("direction")) : CENTER; + /* + We do the space left of ST, with lfliebertjes pointing to the + right from the left stem, and rfliebertjes pointing left from + right stem. + */ + SCM left = (i > 0) ? scm_cdr (last_beaming) : SCM_EOL; + SCM right = st ? scm_car (this_beaming) : SCM_EOL; + + Array<int> full_beams; + Array<int> lfliebertjes; + Array<int> rfliebertjes; + + for (SCM s = left; + scm_is_pair (s); s = scm_cdr (s)) + { + int b = scm_to_int (scm_car (s)); + if (scm_c_memq (scm_car (s), right) != SCM_BOOL_F) + { + full_beams.push (b); + } + else + { + lfliebertjes.push (b); + } + } + for (SCM s = right; + scm_is_pair (s); s = scm_cdr (s)) + { + int b = scm_to_int (scm_car (s)); + if (scm_c_memq (scm_car (s), left) == SCM_BOOL_F) + { + rfliebertjes.push (b); + } + } + + /* + how much to stick out for beams across linebreaks + */ + Real break_overshoot = 3.0; + Real w = (i > 0 && st) ? (xposn - last_xposn) : break_overshoot; + + Real stem_offset = 0.0; + if (i > 0) + { + w += last_stem_width / 2; + stem_offset = -last_stem_width / 2; + } + + if (st) + w += stem_width / 2; + + Real blot = me->get_layout ()->get_dimension (ly_symbol2scm ("blotdiameter")); + Stencil whole = Lookup::beam (slope, w, thick, blot); + Stencil gapped; + + int gap_count = 0; + if (scm_is_number (me->get_property ("gap-count"))) + { + gap_count = scm_to_int (me->get_property ("gap-count")); + gapped = Lookup::beam (slope, w - 2 * gap_length, thick, blot); + + full_beams.sort (default_compare); + if (stem_dir == UP) + full_beams.reverse (); + } + + int k = 0; + for (int j = full_beams.size (); j--;) + { + Stencil b (whole); + + if (k++ < gap_count) + { + b = gapped; + b.translate_axis (gap_length, X_AXIS); + } + b.translate_axis (last_xposn - x0 + stem_offset, X_AXIS); + b.translate_axis (slope * (last_xposn - x0) + bdy * full_beams[j], Y_AXIS); + + the_beam.add_stencil (b); + } + + if (lfliebertjes.size () || rfliebertjes.size ()) + { + Real nw_f; + + if (st) + { + int t = Stem::duration_log (st); + + SCM proc = me->get_property ("flag-width-function"); + SCM result = scm_call_1 (proc, scm_int2num (t)); + nw_f = scm_to_double (result); + } + else + nw_f = break_overshoot / 2; + + /* Half beam should be one note-width, + but let's make sure two half-beams never touch */ + Real lw = nw_f; + Real rw = nw_f; + if (i > 0) + rw = min (nw_f, ((xposn - last_xposn) / 2)); + else + /* + TODO: 0.5 is a guess. + */ + rw = xposn - me->get_bound (LEFT)->extent (xcommon, X_AXIS)[RIGHT] + - 0.5; + + if (st) + lw = min (nw_f, ((xposn - last_xposn) / 2)); + else + lw = me->get_bound (RIGHT)->relative_coordinate (xcommon, X_AXIS) + - last_xposn; + + Stencil rhalf = Lookup::beam (slope, rw, thick, blot); + Stencil lhalf = Lookup::beam (slope, lw, thick, blot); + for (int j = lfliebertjes.size (); j--;) + { + Stencil b (lhalf); + b.translate_axis (last_xposn - x0, X_AXIS); + b.translate_axis (slope * (last_xposn - x0) + bdy * lfliebertjes[j], Y_AXIS); + the_beam.add_stencil (b); + } + for (int j = rfliebertjes.size (); j--;) + { + Stencil b (rhalf); + b.translate_axis (xposn - x0 - rw, X_AXIS); + b.translate_axis (slope * (xposn - x0 -rw) + bdy * rfliebertjes[j], Y_AXIS); + the_beam.add_stencil (b); + } + } + + last_xposn = xposn; + last_stem_width = stem_width; + last_beaming = this_beaming; + } + + the_beam.translate_axis (x0 - me->relative_coordinate (xcommon, X_AXIS), X_AXIS); + the_beam.translate_axis (pos[LEFT], Y_AXIS); + +#if (DEBUG_QUANTING) + SCM quant_score = me->get_property ("quant-score"); + if (to_boolean (me->get_layout ()->lookup_variable (ly_symbol2scm ("debug-beam-quanting"))) + && scm_is_string (quant_score)) + { + + /* + This code prints the demerits for each beam. Perhaps this + should be switchable for those who want to twiddle with the + parameters. + */ + String str; + SCM properties = Font_interface::text_font_alist_chain (me); + + Direction stem_dir = stems.size () ? to_dir (stems[0]->get_property ("direction")) : UP; + + Stencil tm = *unsmob_stencil (Text_interface::interpret_markup + (me->get_layout ()->self_scm (), properties, quant_score)); + the_beam.add_at_edge (Y_AXIS, stem_dir, tm, 1.0, 0); + } +#endif + + return the_beam.smobbed_copy (); +} + +Direction +Beam::get_default_dir (Grob *me) +{ + Drul_array<int> total; + total[UP] = total[DOWN] = 0; + Drul_array<int> count; + count[UP] = count[DOWN] = 0; + Direction d = DOWN; + + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + for (int i = 0; i < stems.size (); i++) + do + { + Grob *s = stems[i]; + Direction sd = get_grob_direction (s); + + int center_distance = max (int (- d * Stem::head_positions (s) [-d]), 0); + int current = sd ? (1 + d * sd) / 2 : center_distance; + + if (current) + { + total[d] += current; + count[d]++; + } + } + while (flip (&d) != DOWN); + + SCM func = me->get_property ("dir-function"); + SCM s = scm_call_2 (func, + scm_cons (scm_int2num (count[UP]), + scm_int2num (count[DOWN])), + scm_cons (scm_int2num (total[UP]), + scm_int2num (total[DOWN]))); + + if (scm_is_number (s) && scm_to_int (s)) + return to_dir (s); + + /* If dir is not determined: get default */ + return to_dir (me->get_property ("neutral-direction")); +} + +/* Set all stems with non-forced direction to beam direction. + Urg: non-forced should become `without/with unforced' direction, + once stem gets cleaned-up. */ +void +Beam::set_stem_directions (Grob *me, Direction d) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + + SCM forcedir = s->get_property ("direction"); + if (!to_dir (forcedir)) + set_grob_direction (s, d); + } +} + +/* + Only try horizontal beams for knees. No reliable detection of + anything else is possible here, since we don't know funky-beaming + settings, or X-distances (slopes!) People that want sloped + knee-beams, should set the directions manually. + + + TODO: + + this routine should take into account the stemlength scoring + of a possible knee/nonknee beam. +*/ +void +Beam::consider_auto_knees (Grob *me) +{ + SCM scm = me->get_property ("auto-knee-gap"); + if (!scm_is_number (scm)) + return; + + Interval_set gaps; + + gaps.set_full (); + + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + Grob *common = common_refpoint_of_array (stems, me, Y_AXIS); + Real staff_space = Staff_symbol_referencer::staff_space (me); + + Array<Interval> head_extents_array; + for (int i = 0; i < stems.size (); i++) + { + Grob *stem = stems[i]; + if (Stem::is_invisible (stem)) + continue; + + Interval head_extents = Stem::head_positions (stem); + if (!head_extents.is_empty ()) + { + head_extents[LEFT] += -1; + head_extents[RIGHT] += 1; + head_extents *= staff_space * 0.5; + + /* + We could subtract beam Y position, but this routine only + sets stem directions, a constant shift does not have an + influence. + */ + head_extents += stem->relative_coordinate (common, Y_AXIS); + + if (to_dir (stem->get_property ("direction"))) + { + Direction stemdir = to_dir (stem->get_property ("direction")); + head_extents[-stemdir] = -stemdir * infinity_f; + } + } + head_extents_array.push (head_extents); + + gaps.remove_interval (head_extents); + } + + Interval max_gap; + Real max_gap_len = 0.0; + + for (int i = gaps.allowed_regions_.size () -1; i >= 0; i--) + { + Interval gap = gaps.allowed_regions_[i]; + + /* + the outer gaps are not knees. + */ + if (isinf (gap[LEFT]) || isinf (gap[RIGHT])) + continue; + + if (gap.length () >= max_gap_len) + { + max_gap_len = gap.length (); + max_gap = gap; + } + } + + Real beam_translation = get_beam_translation (me); + Real beam_thickness = Beam::get_thickness (me); + int beam_count = Beam::get_beam_count (me); + Real height_of_beams = beam_thickness / 2 + + (beam_count - 1) * beam_translation; + Real threshold = scm_to_double (scm) + height_of_beams; + + if (max_gap_len > threshold) + { + int j = 0; + for (int i = 0; i < stems.size (); i++) + { + Grob *stem = stems[i]; + if (Stem::is_invisible (stem)) + continue; + + Interval head_extents = head_extents_array[j++]; + + Direction d = (head_extents.center () < max_gap.center ()) + ? UP : DOWN; + + stem->set_property ("direction", scm_int2num (d)); + + head_extents.intersect (max_gap); + assert (head_extents.is_empty () || head_extents.length () < 1e-6); + } + } +} + +/* Set stem's shorten property if unset. + +TODO: +take some y-position (chord/beam/nearest?) into account +scmify forced-fraction + +This is done in beam because the shorten has to be uniform over the +entire beam. +*/ +void +Beam::set_stem_shorten (Grob *me) +{ + /* + shortening looks silly for x staff beams + */ + if (is_knee (me)) + return; + + Real forced_fraction = 1.0 * forced_stem_count (me) + / visible_stem_count (me); + + int beam_count = get_beam_count (me); + + SCM shorten_list = me->get_property ("beamed-stem-shorten"); + if (shorten_list == SCM_EOL) + return; + + Real staff_space = Staff_symbol_referencer::staff_space (me); + + SCM shorten_elt + = robust_list_ref (beam_count -1, shorten_list); + Real shorten_f = scm_to_double (shorten_elt) * staff_space; + + /* your similar cute comment here */ + shorten_f *= forced_fraction; + + if (shorten_f) + me->set_property ("shorten", scm_make_real (shorten_f)); +} + +/* Call list of y-dy-callbacks, that handle setting of + grob-properties +*/ +MAKE_SCHEME_CALLBACK (Beam, after_line_breaking, 1); +SCM +Beam::after_line_breaking (SCM smob) +{ + Grob *me = unsmob_grob (smob); + + position_beam (me); + return SCM_UNSPECIFIED; +} + +void +Beam::position_beam (Grob *me) +{ + if (!me->is_live ()) + return; + if (to_boolean (me->get_property ("positioning-done"))) + return; + + me->set_property ("positioning-done", SCM_BOOL_T); + + /* Copy to mutable list. */ + SCM s = ly_deep_copy (me->get_property ("positions")); + me->set_property ("positions", s); + + if (scm_car (s) == SCM_BOOL_F) + { + // one wonders if such genericity is necessary --hwn. + SCM callbacks = me->get_property ("position-callbacks"); + for (SCM i = callbacks; scm_is_pair (i); i = scm_cdr (i)) + scm_call_1 (scm_car (i), me->self_scm ()); + } + + set_stem_lengths (me); +} + +void +set_minimum_dy (Grob *me, Real *dy) +{ + if (*dy) + { + /* + If dy is smaller than the smallest quant, we + get absurd direction-sign penalties. + */ + + Real ss = Staff_symbol_referencer::staff_space (me); + Real thickness = Beam::get_thickness (me) / ss; + Real slt = Staff_symbol_referencer::line_thickness (me) / ss; + Real sit = (thickness - slt) / 2; + Real inter = 0.5; + Real hang = 1.0 - (thickness - slt) / 2; + + *dy = sign (*dy) * max (fabs (*dy), + min (min (sit, inter), hang)); + } +} + +/* + Compute a first approximation to the beam slope. +*/ +MAKE_SCHEME_CALLBACK (Beam, least_squares, 1); +SCM +Beam::least_squares (SCM smob) +{ + Grob *me = unsmob_grob (smob); + + int count = visible_stem_count (me); + Interval pos (0, 0); + + if (count < 1) + { + me->set_property ("positions", ly_interval2scm (pos)); + return SCM_UNSPECIFIED; + } + + Array<Real> x_posns; + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + Grob *commonx = common_refpoint_of_array (stems, me, X_AXIS); + Grob *commony = common_refpoint_of_array (stems, me, Y_AXIS); + + Real my_y = me->relative_coordinate (commony, Y_AXIS); + + Grob *fvs = first_visible_stem (me); + Grob *lvs = last_visible_stem (me); + + Interval ideal (Stem::get_stem_info (fvs).ideal_y_ + + fvs->relative_coordinate (commony, Y_AXIS) -my_y, + Stem::get_stem_info (lvs).ideal_y_ + + lvs->relative_coordinate (commony, Y_AXIS) - my_y); + + Real x0 = first_visible_stem (me)->relative_coordinate (commonx, X_AXIS); + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + + Real x = s->relative_coordinate (commonx, X_AXIS) - x0; + x_posns.push (x); + } + Real dx = last_visible_stem (me)->relative_coordinate (commonx, X_AXIS) - x0; + + Real y = 0; + Real slope = 0; + Real dy = 0; + + if (!ideal.delta ()) + { + Interval chord (Stem::chord_start_y (first_visible_stem (me)), + Stem::chord_start_y (last_visible_stem (me))); + + /* Simple beams (2 stems) on middle line should be allowed to be + slightly sloped. + + However, if both stems reach middle line, + ideal[LEFT] == ideal[RIGHT] and ideal.delta () == 0. + + For that case, we apply artificial slope */ + if (!ideal[LEFT] && chord.delta () && count == 2) + { + /* FIXME. -> UP */ + Direction d = (Direction) (sign (chord.delta ()) * UP); + pos[d] = get_thickness (me) / 2; + pos[-d] = -pos[d]; + } + else + { + pos = ideal; + } + + /* + For broken beams this doesn't work well. In this case, the + slope esp. of the first part of a broken beam should predict + where the second part goes. + */ + me->set_property ("least-squares-dy", + scm_make_real (pos[RIGHT] - pos[LEFT])); + } + else + { + Array<Offset> ideals; + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + if (Stem::is_invisible (s)) + continue; + ideals.push (Offset (x_posns[i], + Stem::get_stem_info (s).ideal_y_ + + s->relative_coordinate (commony, Y_AXIS) + - my_y)); + } + + minimise_least_squares (&slope, &y, ideals); + + dy = slope * dx; + + set_minimum_dy (me, &dy); + me->set_property ("least-squares-dy", scm_make_real (dy)); + pos = Interval (y, (y + dy)); + } + + /* + "position" is relative to the staff. + */ + scale_drul (&pos, 1 / Staff_symbol_referencer::staff_space (me)); + + me->set_property ("positions", ly_interval2scm (pos)); + + return SCM_UNSPECIFIED; +} + +/* + We can't combine with previous function, since check concave and + slope damping comes first. + + TODO: we should use the concaveness to control the amount of damping + applied. +*/ +MAKE_SCHEME_CALLBACK (Beam, shift_region_to_valid, 1); +SCM +Beam::shift_region_to_valid (SCM grob) +{ + Grob *me = unsmob_grob (grob); + /* + Code dup. + */ + Array<Real> x_posns; + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + Grob *commonx = common_refpoint_of_array (stems, me, X_AXIS); + Grob *commony = common_refpoint_of_array (stems, me, Y_AXIS); + + Grob *fvs = first_visible_stem (me); + + if (!fvs) + return SCM_UNSPECIFIED; + + Real x0 = fvs->relative_coordinate (commonx, X_AXIS); + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + + Real x = s->relative_coordinate (commonx, X_AXIS) - x0; + x_posns.push (x); + } + + Grob *lvs = last_visible_stem (me); + if (!lvs) + return SCM_UNSPECIFIED; + + Real dx = lvs->relative_coordinate (commonx, X_AXIS) - x0; + + Drul_array<Real> pos = ly_scm2interval (me->get_property ("positions")); + + scale_drul (&pos, Staff_symbol_referencer::staff_space (me)); + + Real dy = pos[RIGHT] - pos[LEFT]; + Real y = pos[LEFT]; + Real slope = dx ? dy / dx : 0.0; + + /* + Shift the positions so that we have a chance of finding good + quants (i.e. no short stem failures.) + */ + Interval feasible_left_point; + feasible_left_point.set_full (); + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + if (Stem::is_invisible (s)) + continue; + + Direction d = Stem::get_direction (s); + + Real left_y + = Stem::get_stem_info (s).shortest_y_ + - slope * x_posns [i]; + + /* + left_y is now relative to the stem S. We want relative to + ourselves, so translate: + */ + left_y + += + s->relative_coordinate (commony, Y_AXIS) + - me->relative_coordinate (commony, Y_AXIS); + + Interval flp; + flp.set_full (); + flp[-d] = left_y; + + feasible_left_point.intersect (flp); + } + + if (feasible_left_point.is_empty ()) + warning (_ ("no viable initial configuration found: may not find good beam slope")); + else if (!feasible_left_point.contains (y)) + { + if (isinf (feasible_left_point[DOWN])) + y = feasible_left_point[UP] - REGION_SIZE; + else if (isinf (feasible_left_point[UP])) + y = feasible_left_point[DOWN]+ REGION_SIZE; + else + y = feasible_left_point.center (); + } + + pos = Drul_array<Real> (y, (y + dy)); + scale_drul (&pos, 1 / Staff_symbol_referencer::staff_space (me)); + + me->set_property ("positions", ly_interval2scm (pos)); + return SCM_UNSPECIFIED; +} + +/* This neat trick is by Werner Lemberg, + damped = tanh (slope) + corresponds with some tables in [Wanske] CHECKME */ +MAKE_SCHEME_CALLBACK (Beam, slope_damping, 1); +SCM +Beam::slope_damping (SCM smob) +{ + Grob *me = unsmob_grob (smob); + + if (visible_stem_count (me) <= 1) + return SCM_UNSPECIFIED; + + SCM s = me->get_property ("damping"); + Real damping = scm_to_double (s); + + if (damping) + { + Drul_array<Real> pos = ly_scm2interval (me->get_property ("positions")); + scale_drul (&pos, Staff_symbol_referencer::staff_space (me)); + + Real dy = pos[RIGHT] - pos[LEFT]; + + Grob *fvs = first_visible_stem (me); + Grob *lvs = last_visible_stem (me); + + Grob *commonx = fvs->common_refpoint (lvs, X_AXIS); + + Real dx = last_visible_stem (me)->relative_coordinate (commonx, X_AXIS) + - first_visible_stem (me)->relative_coordinate (commonx, X_AXIS); + + Real slope = dy && dx ? dy / dx : 0; + + Real concaveness = robust_scm2double (me->get_property ("concaveness"), 0.0); + + slope = 0.6 * tanh (slope) / (damping + concaveness); + + Real damped_dy = slope * dx; + + set_minimum_dy (me, &damped_dy); + + pos[LEFT] += (dy - damped_dy) / 2; + pos[RIGHT] -= (dy - damped_dy) / 2; + + scale_drul (&pos, 1 / Staff_symbol_referencer::staff_space (me)); + + me->set_property ("positions", ly_interval2scm (pos)); + } + return SCM_UNSPECIFIED; +} + +/* + Report slice containing the numbers that are both in (car BEAMING) + and (cdr BEAMING) +*/ +Slice +where_are_the_whole_beams (SCM beaming) +{ + Slice l; + + for (SCM s = scm_car (beaming); scm_is_pair (s); s = scm_cdr (s)) + { + if (scm_c_memq (scm_car (s), scm_cdr (beaming)) != SCM_BOOL_F) + + l.add_point (scm_to_int (scm_car (s))); + } + + return l; +} + +/* Return the Y position of the stem-end, given the Y-left, Y-right + in POS for stem S. This Y position is relative to S. */ +Real +Beam::calc_stem_y (Grob *me, Grob *s, Grob ** common, + Real xl, Real xr, + Drul_array<Real> pos, bool french) +{ + Real beam_translation = get_beam_translation (me); + + Real r = s->relative_coordinate (common[X_AXIS], X_AXIS) - xl; + Real dy = pos[RIGHT] - pos[LEFT]; + Real dx = xr - xl; + Real stem_y_beam0 = (dy && dx + ? r / dx + * dy + : 0) + pos[LEFT]; + + Direction my_dir = get_grob_direction (s); + SCM beaming = s->get_property ("beaming"); + + Real stem_y = stem_y_beam0; + if (french) + { + Slice bm = where_are_the_whole_beams (beaming); + if (!bm.is_empty ()) + stem_y += beam_translation * bm[-my_dir]; + } + else + { + Slice bm = Stem::beam_multiplicity (s); + if (!bm.is_empty ()) + stem_y += bm[my_dir] * beam_translation; + } + + Real id = me->relative_coordinate (common[Y_AXIS], Y_AXIS) + - s->relative_coordinate (common[Y_AXIS], Y_AXIS); + + return stem_y + id; +} + +/* + Hmm. At this time, beam position and slope are determined. Maybe, + stem directions and length should set to relative to the chord's + position of the beam. */ +void +Beam::set_stem_lengths (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + if (!stems.size ()) + return; + + Grob *common[2]; + for (int a = 2; a--;) + common[a] = common_refpoint_of_array (stems, me, Axis (a)); + + Drul_array<Real> pos = ly_scm2realdrul (me->get_property ("positions")); + Real staff_space = Staff_symbol_referencer::staff_space (me); + scale_drul (&pos, staff_space); + + bool gap = false; + Real thick = 0.0; + if (scm_is_number (me->get_property ("gap-count")) + &&scm_to_int (me->get_property ("gap-count"))) + { + gap = true; + thick = get_thickness (me); + } + + // ugh -> use commonx + Grob *fvs = first_visible_stem (me); + Grob *lvs = last_visible_stem (me); + + Real xl = fvs ? fvs->relative_coordinate (common[X_AXIS], X_AXIS) : 0.0; + Real xr = lvs ? lvs->relative_coordinate (common[X_AXIS], X_AXIS) : 0.0; + + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + if (Stem::is_invisible (s)) + continue; + + bool french = to_boolean (s->get_property ("french-beaming")); + Real stem_y = calc_stem_y (me, s, common, + xl, xr, + pos, french && s != lvs && s!= fvs); + + /* + Make the stems go up to the end of the beam. This doesn't matter + for normal beams, but for tremolo beams it looks silly otherwise. + */ + if (gap) + stem_y += thick * 0.5 * get_grob_direction (s); + + Stem::set_stemend (s, 2 * stem_y / staff_space); + } +} + +void +Beam::set_beaming (Grob *me, Beaming_info_list *beaming) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + Direction d = LEFT; + for (int i = 0; i < stems.size (); i++) + { + /* + Don't overwrite user settings. + */ + + do + { + /* Don't set beaming for outside of outer stems */ + if ((d == LEFT && i == 0) + || (d == RIGHT && i == stems.size () -1)) + continue; + + Grob *st = stems[i]; + SCM beaming_prop = st->get_property ("beaming"); + if (beaming_prop == SCM_EOL + || index_get_cell (beaming_prop, d) == SCM_EOL) + { + int b = beaming->infos_.elem (i).beams_i_drul_[d]; + if (i > 0 + && i < stems.size () -1 + && Stem::is_invisible (st)) + b = min (b, beaming->infos_.elem (i).beams_i_drul_[-d]); + + Stem::set_beaming (st, b, d); + } + } + while (flip (&d) != LEFT); + } +} + +int +Beam::forced_stem_count (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + int f = 0; + for (int i = 0; i < stems.size (); i++) + { + Grob *s = stems[i]; + + if (Stem::is_invisible (s)) + continue; + + /* I can imagine counting those boundaries as a half forced stem, + but let's count them full for now. */ + if (abs (Stem::chord_start_y (s)) > 0.1 + && (Stem::get_direction (s) != Stem::get_default_dir (s))) + f++; + } + return f; +} + +int +Beam::visible_stem_count (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + int c = 0; + for (int i = stems.size (); i--;) + { + if (!Stem::is_invisible (stems[i])) + c++; + } + return c; +} + +Grob * +Beam::first_visible_stem (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + + for (int i = 0; i < stems.size (); i++) + { + if (!Stem::is_invisible (stems[i])) + return stems[i]; + } + return 0; +} + +Grob * +Beam::last_visible_stem (Grob *me) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + for (int i = stems.size (); i--;) + { + if (!Stem::is_invisible (stems[i])) + return stems[i]; + } + return 0; +} + +/* + [TODO] + + handle rest under beam (do_post: beams are calculated now) + what about combination of collisions and rest under beam. + + Should lookup + + rest -> stem -> beam -> interpolate_y_position () +*/ +MAKE_SCHEME_CALLBACK (Beam, rest_collision_callback, 2); +SCM +Beam::rest_collision_callback (SCM element_smob, SCM axis) +{ + Grob *rest = unsmob_grob (element_smob); + (void) axis; + + if (scm_is_number (rest->get_property ("staff-position"))) + return scm_int2num (0); + + assert (scm_to_int (axis) == Y_AXIS); + + Grob *st = unsmob_grob (rest->get_property ("stem")); + Grob *stem = st; + if (!stem) + return scm_make_real (0.0); + Grob *beam = unsmob_grob (stem->get_property ("beam")); + if (!beam + || !Beam::has_interface (beam) + || !Beam::visible_stem_count (beam)) + return scm_make_real (0.0); + + Drul_array<Real> pos (0, 0); + SCM s = beam->get_property ("positions"); + if (scm_is_pair (s) && scm_is_number (scm_car (s))) + pos = ly_scm2interval (s); + Real staff_space = Staff_symbol_referencer::staff_space (rest); + + scale_drul (&pos, staff_space); + + Real dy = pos[RIGHT] - pos[LEFT]; + + // ugh -> use commonx + Real x0 = first_visible_stem (beam)->relative_coordinate (0, X_AXIS); + Real dx = last_visible_stem (beam)->relative_coordinate (0, X_AXIS) - x0; + Real slope = dy && dx ? dy / dx : 0; + + Direction d = Stem::get_direction (stem); + Real stem_y = pos[LEFT] + (stem->relative_coordinate (0, X_AXIS) - x0) * slope; + + Real beam_translation = get_beam_translation (beam); + Real beam_thickness = Beam::get_thickness (beam); + + /* + TODO: this is not strictly correct for 16th knee beams. + */ + int beam_count + = Stem::beam_multiplicity (stem).length () + 1; + + Real height_of_my_beams = beam_thickness / 2 + + (beam_count - 1) * beam_translation; + Real beam_y = stem_y - d * height_of_my_beams; + + Grob *common_y = rest->common_refpoint (beam, Y_AXIS); + + Real rest_dim = rest->extent (common_y, Y_AXIS)[d]; + Real minimum_distance + = + staff_space * (robust_scm2double (stem->get_property ("stemlet-length"), 0.0) + + robust_scm2double (rest->get_property ("minimum-distance"), 0.0)); + + Real shift = d * min (((beam_y - d * minimum_distance) - rest_dim) * d, 0.0); + + shift /= staff_space; + Real rad = Staff_symbol_referencer::line_count (rest) * staff_space / 2; + + /* Always move discretely by half spaces */ + shift = ceil (fabs (shift * 2.0)) / 2.0 * sign (shift); + + /* Inside staff, move by whole spaces*/ + if ((rest->extent (common_y, Y_AXIS)[d] + staff_space * shift) * d + < rad + || (rest->extent (common_y, Y_AXIS)[-d] + staff_space * shift) * -d + < rad) + shift = ceil (fabs (shift)) * sign (shift); + + return scm_make_real (staff_space * shift); +} + +bool +Beam::is_knee (Grob *me) +{ + SCM k = me->get_property ("knee"); + if (scm_is_bool (k)) + return ly_scm2bool (k); + + bool knee = false; + int d = 0; + for (SCM s = me->get_property ("stems"); scm_is_pair (s); s = scm_cdr (s)) + { + Direction dir = get_grob_direction (unsmob_grob (scm_car (s))); + if (d && d != dir) + { + knee = true; + break; + } + d = dir; + } + + me->set_property ("knee", ly_bool2scm (knee)); + + return knee; +} + +int +Beam::get_direction_beam_count (Grob *me, Direction d) +{ + Link_array<Grob> stems + = extract_grob_array (me, ly_symbol2scm ("stems")); + int bc = 0; + + for (int i = stems.size (); i--;) + { + /* + Should we take invisible stems into account? + */ + if (Stem::get_direction (stems[i]) == d) + bc = max (bc, (Stem::beam_multiplicity (stems[i]).length () + 1)); + } + + return bc; +} + +ADD_INTERFACE (Beam, "beam-interface", + "A beam. \n\n" + "The @code{thickness} property is the weight of beams, and is measured " + "in staffspace", + "knee positioning-done position-callbacks " + "concaveness dir-function quant-score auto-knee-gap gap " + "gap-count chord-tremolo beamed-stem-shorten shorten least-squares-dy " + "damping inspect-quants flag-width-function neutral-direction positions space-function " + "thickness"); + _______________________________________________ Lilypond-cvs mailing list Lilypond-cvs@gnu.org http://lists.gnu.org/mailman/listinfo/lilypond-cvs