X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fsimple-spacer.cc;h=7ad8eb3795a7d79b7dbee5b9126226a4bb643644;hb=31a565c0bad19d6c9206a72405b90dd47b0d4968;hp=905158ae1f70fa099b233d87a8dc4d1d269fc257;hpb=d7416352b825c3e9b4858e1ddcf14f0c00e26d89;p=lilypond.git diff --git a/lily/simple-spacer.cc b/lily/simple-spacer.cc index 905158ae1f..7ad8eb3795 100644 --- a/lily/simple-spacer.cc +++ b/lily/simple-spacer.cc @@ -3,14 +3,15 @@ source file of the GNU LilyPond music typesetter - (c) 1999--2000 Han-Wen Nienhuys + (c) 1999--2004 Han-Wen Nienhuys TODO: - add support for different stretch/shrink constants? */ - +#include #include +#include // isinf #include "simple-spacer.hh" #include "paper-column.hh" @@ -18,13 +19,59 @@ #include "rod.hh" #include "warn.hh" #include "column-x-positions.hh" +#include "spaceable-grob.hh" #include "dimensions.hh" + +/* + A simple spacing constraint solver. The approach: + + Stretch the line uniformly until none of the constraints (rods) + block. It then is very wide. + + Compress until the next constraint blocks, + + Mark the springs over the constrained part to be non-active. + + Repeat with the smaller set of non-active constraints, until all + constraints blocked, or until the line is as short as desired. + + This is much simpler, and much much faster than full scale + Constrained QP. On the other hand, a situation like this will not + be typeset as dense as possible, because + + c4 c4 c4 c4 + veryveryverylongsyllable2 veryveryverylongsyllable2 + " "4 veryveryverylongsyllable2 syllable4 + + + can be further compressed to + + + c4 c4 c4 c4 + veryveryverylongsyllable2 veryveryverylongsyllable2 + " "4 veryveryverylongsyllable2 syllable4 + + + Perhaps this is not a bad thing, because the 1st looks better anyway. */ + + +/* + + positive force = expanding, negative force = compressing. + +*/ + Simple_spacer::Simple_spacer () { - force_f_ = 0.; - indent_f_ =0.0; - default_space_f_ = 20 PT; + /* + Give an extra penalty for compression. Needed to avoid compressing + tightly spaced lines. + */ + active_count_ = 0; + force_ = 0.; + indent_ =0.0; + default_space_ = 20 PT; } void @@ -35,18 +82,34 @@ Simple_spacer::add_rod (int l, int r, Real dist) programming_error ("Weird minimum distance. Ignoring"); return; } - - + Real c = range_stiffness (l,r); + if (isinf (c)) + { + /* + If a spring is fixed, we have to do something here: + we let the rod override the spring. + */ + Real total_dist = 0.; + for (int i = l ; i < r; i++) + total_dist += springs_[i].ideal_; + + if (total_dist < dist) + for (int i = l ; i < r; i++) + springs_[i].ideal_ *= dist/total_dist; + + return; + } + Real d = range_ideal_len (l,r); Real block_stretch = dist - d; Real block_force = c * block_stretch; - force_f_ = force_f_ >? block_force; + force_ = force_ >? block_force; for (int i=l; i < r; i++) - springs_[i].block_force_f_ = block_force >? - springs_[i].block_force_f_ ; + springs_[i].block_force_ = block_force >? + springs_[i].block_force_ ; } Real @@ -54,7 +117,7 @@ Simple_spacer::range_ideal_len (int l, int r) const { Real d =0.; for (int i=l; i < r; i++) - d += springs_[i].ideal_f_; + d += springs_[i].ideal_; return d; } @@ -63,7 +126,10 @@ Simple_spacer::range_stiffness (int l, int r) const { Real den =0.0; for (int i=l; i < r; i++) - den += 1 / springs_[i].hooke_f_; + { + if (springs_[i].is_active_) + den += 1 / springs_[i].hooke_; + } return 1 / den; } @@ -73,9 +139,9 @@ Simple_spacer::active_blocking_force () const { Real bf = - infinity_f; for (int i=0; i < springs_.size (); i++) - if (springs_[i].active_b_) + if (springs_[i].is_active_) { - bf = bf >? springs_[i].block_force_f_; + bf = bf >? springs_[i].block_force_; } return bf; } @@ -83,23 +149,41 @@ Simple_spacer::active_blocking_force () const Real Simple_spacer::active_springs_stiffness () const { - Real den = 0.0; - for (int i=0; i < springs_.size (); i++) - if (springs_[i].active_b_) - { - den += 1 / springs_[i].hooke_f_; - } - return 1/den; + Real stiff = range_stiffness (0, springs_.size ()); + if (isinf (stiff)) + { + /* + all springs are inactive. Take the stiffness of the + latest spring to block. + */ + + Real max_block_force = -infinity_f; + int max_i = -1; + for (int i=0; i < springs_.size (); i++) + { + if (springs_[i].block_force_ > max_block_force) + { + max_i = i; + max_block_force = springs_[i].block_force_; + } + } + + stiff = springs_[max_i].hooke_; + } + return stiff; } void Simple_spacer::set_active_states () { - // safe, since - // force is only copied. + /* float comparison is safe, since force is only copied. */ for (int i=0 ; i = force_f_) - springs_[i].active_b_ = false; + if (springs_[i].is_active_ + && springs_[i].block_force_ >= force_) + { + springs_[i].is_active_ = false; + active_count_ --; + } } Real @@ -107,39 +191,28 @@ Simple_spacer::configuration_length () const { Real l =0.; for (int i=0; i < springs_.size (); i++) - l += springs_[i].length (force_f_); + l += springs_[i].length (force_); return l; } -Real -Spring_description::length (Real f) const -{ - if (!active_b_) - f = block_force_f_; - return ideal_f_ + f / hooke_f_ ; -} - bool -Simple_spacer::active_b () const +Simple_spacer::is_active () const { - for (int i=0; i < springs_.size (); i++) - if (springs_[i].active_b_) - return true; - return false; + return active_count_; } void Simple_spacer::my_solve_linelen () { - while (active_b ()) + while (is_active ()) { - force_f_ = active_blocking_force (); + force_ = active_blocking_force (); Real conf = configuration_length (); - if (conf < line_len_f_) + if (conf < line_len_) { - force_f_ += (line_len_f_ - conf) * active_springs_stiffness (); + force_ += (line_len_ - conf) * active_springs_stiffness (); break; } else @@ -151,107 +224,313 @@ Simple_spacer::my_solve_linelen () void Simple_spacer::my_solve_natural_len () { - while (active_b ()) + Real line_len_force = 0.0; + + while (is_active ()) { - force_f_ = active_blocking_force () >? 0.0; + force_ = active_blocking_force () >? 0.0; + Real conf = configuration_length (); - if (force_f_ < 1e-8) // ugh., + if (conf < line_len_) + { + line_len_force = force_ + + (line_len_ - conf) + * active_springs_stiffness(); + } + + if (force_ < 1e-8) // ugh., break; set_active_states (); } + + force_ = line_len_force; } -void -Simple_spacer::add_columns (Link_array cols) +LY_DEFINE(ly_solve_spring_rod_problem, "ly:solve-spring-rod-problem", + 4, 1, 0, (SCM springs, SCM rods, SCM length, SCM ragged), + "Solve a spring and rod problem for @var{count} objects, that " + "are connected by @var{count-1} springs, and an arbitrary number of rods " + "Springs have the format (ideal, hooke) and rods (idx1, idx2, distance) " + "@var{length} is a number, @var{ragged} a boolean " + "Return: a list containing the force (#f for non-satisfied constraints) " + "followed by the @var{spring-count}+1 positions of the objects. " + ) { - for (int i=0; i < cols.size () - 1; i++) + int len = scm_ilength (springs); + if (len == 0) + return scm_list_2 (scm_from_double (0.0), scm_from_double (0.0)); + + SCM_ASSERT_TYPE (len >= 0, springs, SCM_ARG1, __FUNCTION__, "list of springs"); + SCM_ASSERT_TYPE (scm_ilength (rods) >= 0, rods, SCM_ARG2, __FUNCTION__, "list of rods"); + SCM_ASSERT_TYPE (scm_is_number (length) || length == SCM_BOOL_F, + length, SCM_ARG3, __FUNCTION__, "number or #f"); + + + bool is_ragged = ragged == SCM_BOOL_T; + Simple_spacer spacer; + for (SCM s = springs; scm_is_pair (s); s = scm_cdr (s)) { - Paper_column * c = cols [i]; - Column_spring *to_next = 0; - for (int j =0; !to_next && j < c->springs_.size( ); j++) - { - Column_spring &sp = c->springs_ [j]; - if (sp.other_l_ != cols[i+1]) - continue; + Real ideal = scm_to_double (scm_caar (s)); + Real hooke = scm_to_double (scm_cadar (s)); - to_next = &sp; - } + spacer.add_spring (ideal, hooke); + } - Spring_description desc; - if (to_next) - { - desc.hooke_f_ = to_next->strength_f_; - desc.ideal_f_ = to_next->distance_f_; - } - else - { - desc.hooke_f_ = 1.0; - desc.ideal_f_ = default_space_f_; - } + for (SCM s = rods; scm_is_pair (s); s = scm_cdr (s)) + { + SCM entry = scm_car (s); + int l = scm_to_int (scm_car (entry)); + int r = scm_to_int (scm_cadr (entry)); + entry = scm_cddr (entry); + + Real distance = scm_to_double (scm_car (entry)); + spacer.add_rod (l, r, distance); + } - if (!desc.sane_b ()) - { - programming_error ("Insane spring found. Setting to unit spring."); - desc.hooke_f_ = 1.0; - desc.ideal_f_ = 1.0; - } + spacer.line_len_ = scm_to_double (length); - desc.block_force_f_ = - desc.hooke_f_ * desc.ideal_f_; // block at distance 0 - springs_.push (desc); + if (is_ragged) + spacer.my_solve_natural_len (); + else + spacer.my_solve_linelen (); + + Array posns; + posns.push (0.0); + for (int i = 0; i < spacer.springs_.size(); i++) + { + Real l = spacer.springs_[i].length ((is_ragged) ? 0.0 : spacer.force_); + posns.push (posns.top() + l); + } + + + + SCM force_return = SCM_BOOL_F; + if (!isinf (spacer.force_) + && spacer.is_active ()) + { + force_return = scm_from_double (spacer.force_); + } + + if (is_ragged + && posns.top () > spacer.line_len_) + { + force_return = SCM_BOOL_F; + } + + SCM retval= SCM_EOL; + for (int i = posns.size(); i--;) + { + retval = scm_cons (scm_from_double (posns[i]), retval); } + + retval = scm_cons (force_return, retval); + return retval; +} + + +/****************************************************************/ + +Spring_description::Spring_description () +{ + ideal_ =0.0; + hooke_ =0.0; + is_active_ = true; + block_force_ = 0.0; +} + + +bool +Spring_description::is_sane () const +{ + return (hooke_ > 0) + && ideal_ > 0 + && !isinf (ideal_) && !isnan (ideal_); +} + +Real +Spring_description::length (Real f) const +{ + if (!is_active_) + f = block_force_; + return ideal_ + f / hooke_ ; +} +/****************************************************************/ + + +/* - for (int i=0; i < cols.size () - 1; i++) + TODO: should a add penalty for widely varying spring forces (caused + by constraints, eg. + + + ===== + | | + o|o| x ##x + + + The ## forces the notes apart; we shouldn't allow the O's to touch + this closely. + + */ +void +Simple_spacer_wrapper::solve (Column_x_positions *positions, bool ragged) +{ + if (ragged) + spacer_->my_solve_natural_len (); + else + spacer_->my_solve_linelen (); + + positions->force_ = spacer_->force_; + + /* + We used to have a penalty for compression, no matter what, but that + fucked up wtk1-fugue2 (taking 3 full pages.) + */ + positions->config_.push (spacer_->indent_); + for (int i=0; i < spacer_->springs_.size (); i++) { - Array * rods = &cols [i]->minimal_dists_; - for (int j =0; j < rods->size( ); j++) - { - int oi = cols.find_i (rods->elem (j).other_l_ ); - if (oi >= 0) - { - add_rod (i, oi, rods->elem (j).distance_f_); - } - } + Real l = spacer_->springs_[i].length ((ragged) ? 0.0 : spacer_->force_); + positions->config_.push (positions->config_.top () + l); + /* + we have l>= 0 here, up to rounding errors + */ + } + + /* + For raggedright, we must have a measure of music density: this is + to prevent lots of short lines (which all have force = 0). + */ + if (ragged) + { + positions->satisfies_constraints_ = + positions->config_.top () < spacer_->line_len_ ; } + + positions->cols_ = spaced_cols_; + positions->loose_cols_ = loose_cols_; + positions->satisfies_constraints_ = + positions->satisfies_constraints_ && spacer_->is_active (); + /* - TODO: should support natural length on only the last line. + Check if breaking constraints are met. */ - if (line_len_f_ < 0) - my_solve_natural_len (); - else - my_solve_linelen (); + bool break_satisfy = true; + int sz = positions->cols_.size (); + for (int i = sz; i--; ) + { + SCM p = positions->cols_[i]->get_property ( "penalty"); + if (scm_is_number (p)) + { + if (scm_to_double (p) < -9999) + break_satisfy = break_satisfy && (i == 0 || i == sz -1); + if (scm_to_double (p) > 9999) + break_satisfy = break_satisfy && !(i == 0 || i == sz -1); + } + + } + + positions->satisfies_constraints_ = + positions->satisfies_constraints_ && break_satisfy; } void -Simple_spacer::solve (Column_x_positions *positions) const +Simple_spacer::add_spring (Real ideal, Real hooke) { - positions->force_f_ = force_f_; + Spring_description desc; + + desc.ideal_ = ideal; + desc.hooke_ = hooke; + if (!desc.is_sane ()) + { + programming_error ("Insane spring found. Setting to unit spring."); + + desc.hooke_ = 1.0; + desc.ideal_ = 1.0; + } - positions->config_.push (indent_f_); - for (int i=0; i config_.push (positions->config_.top () + springs_[i].length (force_f_)); + desc.is_active_ = false; } - - positions->satisfies_constraints_b_ = (line_len_f_ < 0) || active_b (); + else + { + /* + desc.is_active_ ? + */ + desc.block_force_ = - desc.hooke_ * desc.ideal_; // block at distance 0 + + active_count_ ++; + } + springs_.push (desc); } +void +Simple_spacer_wrapper::add_columns (Link_array const &icols) +{ + Link_array cols (icols); + + for (int i = cols.size (); i--;) + if (scm_is_pair (cols[i]->get_property ("between-cols"))) + { + loose_cols_.push (cols[i]); + cols.del (i); + } + + spaced_cols_ = cols; + for (int i=0; i < cols.size () - 1; i++) + { + Spring_smob *spring = 0; + + for (SCM s = cols[i]->get_property ("ideal-distances"); + !spring && scm_is_pair (s); + s = scm_cdr (s)) + { + Spring_smob *sp = unsmob_spring (scm_car (s)); + + + if (sp->other_ == cols[i+1]) + spring = sp; + } + if (!spring) + programming_error (_f ("No spring between column %d and next one", + Paper_column::get_rank (cols[i]) + )); -Spring_description::Spring_description( ) -{ - ideal_f_ =0.0; - hooke_f_ =0.0; - active_b_ = true; - block_force_f_ = 0.0; + Real ideal = (spring) ? spring->distance_ : spacer_->default_space_; + Real hooke = (spring) ? spring->strength_ : 1.0; + + spacer_->add_spring (ideal, hooke); + } + + for (int i=0; i < cols.size () - 1; i++) + { + for (SCM s = Spaceable_grob::get_minimum_distances (cols[i]); + scm_is_pair (s); s = scm_cdr (s)) + { + Grob * other = unsmob_grob (scm_caar (s)); + int oi = cols.find_index (other); + if (oi >= 0) + { + spacer_->add_rod (i, oi, scm_to_double (scm_cdar (s))); + } + } + } } +Simple_spacer_wrapper::Simple_spacer_wrapper () +{ + spacer_ = new Simple_spacer (); +} -bool -Spring_description::sane_b () const +Simple_spacer_wrapper::~Simple_spacer_wrapper () { - return (hooke_f_ > 0) && ! isinf (ideal_f_) && !isnan (ideal_f_); + delete spacer_; } +Simple_spacer_wrapper::Simple_spacer_wrapper (Simple_spacer_wrapper const&) +{ +}