From: Joe Neeman <joeneeman@gmail.com>
Date: Sun, 9 Nov 2008 02:26:17 +0000 (-0800)
Subject: Keep more detailed track of compressed lines in page breaking.
X-Git-Tag: release/2.13.1-1~61^2~14
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=4d040126cfd89587730265e549e3d28161642275;p=lilypond.git

Keep more detailed track of compressed lines in page breaking.
---

diff --git a/lily/include/constrained-breaking.hh b/lily/include/constrained-breaking.hh
index 157411a83c..62c5813dc4 100644
--- a/lily/include/constrained-breaking.hh
+++ b/lily/include/constrained-breaking.hh
@@ -33,6 +33,14 @@ struct Line_details {
 
   bool title_;
 
+  /* The page-breaker deals with forbidden page breaks by "compressing"
+     two Line_detailses into one. The following fields are used by the
+     page-breaker to keep track of this. If the number of fields needed
+     by the page-breaker grows, it might be a good idea to create a separate
+     class. */
+  int compressed_lines_count_;
+  int compressed_nontitle_lines_count_;
+
   Line_details ()
   {
     force_ = infinity_f;
@@ -47,6 +55,8 @@ struct Line_details {
     page_penalty_ = 0;
     turn_penalty_ = 0;
     title_ = false;
+    compressed_lines_count_ = 0;
+    compressed_nontitle_lines_count_ = 0;
   }
 
   Line_details (Prob *pb)
@@ -64,6 +74,8 @@ struct Line_details {
     page_penalty_ = robust_scm2double (pb->get_property ("page-break-penalty"), 0);
     turn_penalty_ = robust_scm2double (pb->get_property ("page-turn-penalty"), 0);
     title_ = to_boolean (pb->get_property ("is-title"));
+    compressed_lines_count_ = 0;
+    compressed_nontitle_lines_count_ = 0;
   }
 };
 
diff --git a/lily/include/page-breaking.hh b/lily/include/page-breaking.hh
index 0070a980ca..71aff9386e 100644
--- a/lily/include/page-breaking.hh
+++ b/lily/include/page-breaking.hh
@@ -129,11 +129,14 @@ protected:
   vsize current_configuration_count () const;
   Line_division current_configuration (vsize configuration_index) const;
   Page_spacing_result space_systems_on_n_pages (vsize configuration_index,
-					   vsize n, vsize first_page_num);
+						vsize n, vsize first_page_num);
   Page_spacing_result space_systems_on_n_or_one_more_pages (vsize configuration_index, vsize n,
-						       vsize first_page_num);
+							    vsize first_page_num);
   Page_spacing_result space_systems_on_best_pages (vsize configuration_index,
-					      vsize first_page_num);
+						   vsize first_page_num);
+  Page_spacing_result space_systems_with_fixed_number_per_page (vsize configuration_index,
+								int systems_per_page,
+								vsize first_page_num);
   Page_spacing_result pack_systems_on_least_pages (vsize configuration_index,
 						   vsize first_page_num);
   vsize min_page_count (vsize configuration_index, vsize first_page_num);
diff --git a/lily/page-breaking.cc b/lily/page-breaking.cc
index a5fe6278d0..8228910080 100644
--- a/lily/page-breaking.cc
+++ b/lily/page-breaking.cc
@@ -36,13 +36,12 @@ compress_lines (const vector<Line_details> &orig)
 	  compressed.extent_[UP] = old.extent_[UP] + orig[i].extent_.length () + old.padding_;
 	  compressed.space_ += old.space_;
 	  compressed.inverse_hooke_ += old.inverse_hooke_;
-	  compressed.title_ = old.title_;
 
-	  /* we don't need the force_ field for the vertical spacing,
-	     so we use force_ = n to signal that the line was compressed,
-	     reducing the number of lines by n (and force_ = 0 otherwise).
-	     This makes uncompression much easier. */
-	  compressed.force_ = old.force_ + 1;
+	  compressed.compressed_lines_count_ = old.compressed_lines_count_ + 1;
+	  compressed.compressed_nontitle_lines_count_ =
+	    old.compressed_nontitle_lines_count_ + (compressed.title_ ? 0 : 1);
+
+	  compressed.title_ = compressed.title_ && old.title_;
 	  ret.back () = compressed;
 	}
       else
@@ -68,7 +67,7 @@ uncompress_solution (vector<vsize> const &systems_per_page,
     {
       int compressed_count = 0;
       for (vsize j = start_sys; j < start_sys + systems_per_page[i]; j++)
-	compressed_count += (int)compressed[j].force_;
+	compressed_count += compressed[j].compressed_lines_count_;
 
       ret.push_back (systems_per_page[i] + compressed_count);
       start_sys += systems_per_page[i];
@@ -802,6 +801,13 @@ Page_breaking::space_systems_on_best_pages (vsize configuration, vsize first_pag
   return finalize_spacing_result (configuration, best);
 }
 
+Page_spacing_result space_systems_with_fixed_number_per_page (vsize configuration_index,
+							      int systems_per_page,
+							      vsize first_page_num)
+{
+  return Page_spacing_result ();
+}
+
 Page_spacing_result
 Page_breaking::pack_systems_on_least_pages (vsize configuration, vsize first_page_num)
 {