[PATCH] New margin handling - final version

[Michael Käppler]

Hi all,
thanks to Joe's latest patch concerning the system-count issue I 
concatenated now all the changes in one patch and rewrote
the commit message. Could please somebody run the regression test suite 
and build the docs to see if all bugs have gone.
This doesn't include the margin scaling patch I posted recently for review.

Regards,
Michael

>From 5e0663dfcf01e68e26572ec7979b9580ab26ea5c Mon Sep 17 00:00:00 2001
From: =?utf-8?q?Michael=20K=C3=A4ppler?= <address@hidden>
Date: Wed, 9 Sep 2009 11:48:35 +0200
Subject: [PATCH] Introduce new handling for paper margin settings.

* Make default margins accessible in ly/paper-defaults-init.ly

* Introduce a new method: Output_def::normalize (). It checks,
  whether left-margin, right-margin and/or line-width are set.
  Afterwards it computes missing values or takes defaults, if
  necessary. There is no need to specify line-width manually now.

* Make right-margin work

* If only line-width is set, the current behaviour persists.
  (Systems are centered)

* Output a warning if the margin values don't fit with each other

* Modify lilypond-book to get rid of the
  (define line-width (- line-width 3\mm)) stuff and introduce
  line-width-cropping for compatibility.
---
 input/regression/paper-margins.ly |   60 +++++++++++
 lily/book.cc                      |    1 +
 lily/include/output-def.hh        |    3 +-
 lily/output-def.cc                |   92 ++++++++++++++++-
 lily/paper-book.cc                |   11 ++-
 ly/paper-defaults-init.ly         |  206 ++++++++++++++++++++-----------------
 scm/paper.scm                     |   18 ++--
 scripts/lilypond-book.py          |    2 +-
 8 files changed, 285 insertions(+), 108 deletions(-)
 create mode 100644 input/regression/paper-margins.ly

diff --git a/input/regression/paper-margins.ly 
b/input/regression/paper-margins.ly
new file mode 100644
index 0000000..2d9b5dc
--- /dev/null
+++ b/input/regression/paper-margins.ly
@@ -0,0 +1,60 @@
+\version "2.13.4"
+
+\header {
+  texidoc = "Paper margin settings don't have to be complete. Missing values 
are added automatically, finally 
+             everything is checked for consistency."
+}
+
+#(set-default-paper-size "a4")
+
+someNotes = \relative c' { \repeat unfold 40 { c4 d e f }}
+
+\book {
+  \bookpart {
+    \paper { }
+    \markup { If no paper settings are specified, default values are used. }   
 
+    \score { \someNotes }
+  }
+  \bookpart {
+    \paper {
+      left-margin = 40 \mm
+    }
+    \markup { You may also specify only some margins. Missing values are 
added, if possible. }
+    \markup { Here only left-margin is given, right-margin will remain 
default. }
+    \score { \someNotes }
+  }
+  \bookpart {
+    \paper {
+      right-margin = 40 \mm
+    }
+    \markup { Here only right-margin is given, left-margin will remain 
default. }
+    \score { \someNotes }
+  }
+  \bookpart {
+    \paper {
+      line-width = 100 \mm
+    }
+    \markup { If only line-width is given, the systems are vertically 
centered. }
+    \score { \someNotes }
+  }
+  \bookpart {
+    \paper {
+      left-margin = 20 \mm
+      right-margin = 40 \mm
+      line-width = 100 \mm
+    }
+    \markup { If you specify line-margin, right-margin and line-width, the 
values must be consistent. }
+    \markup { In case they are not, default margins are set and a warning is 
printed. }
+    \score { \someNotes }
+  }
+  \bookpart {
+    \paper {
+      left-margin = 20 \mm
+      right-margin = 40 \mm
+      line-width = 200 \mm
+      check-consistency = ##f
+    }
+    \markup { You can avoid this check with settings check-consistency to 
false in the paper block. }
+    \score { \someNotes }
+  }
+}
diff --git a/lily/book.cc b/lily/book.cc
index 303af1b..86eeda1 100644
--- a/lily/book.cc
+++ b/lily/book.cc
@@ -277,6 +277,7 @@ Book::process (Output_def *default_paper,
     }
   else
     {
+      paper_book->paper_->normalize ();
       /* Process scores */
   /* Render in order of parsing.  */
       for (SCM s = scm_reverse (scores_); scm_is_pair (s); s = scm_cdr (s))
diff --git a/lily/include/output-def.hh b/lily/include/output-def.hh
index b683cc6..9e28d18 100644
--- a/lily/include/output-def.hh
+++ b/lily/include/output-def.hh
@@ -58,13 +58,14 @@ public:
   SCM c_variable (string id) const;
   SCM lookup_variable (SCM sym) const;
   void set_variable (SCM sym, SCM val);
+  void normalize ();
   Real get_dimension (SCM symbol) const;
 };
 SCM get_font_table (Output_def *def);
 void assign_context_def (Output_def *m, SCM transdef);
 SCM find_context_def (Output_def const *m, SCM name);
 
-Interval line_dimensions_int (Output_def*def, int);
+Interval line_dimensions_int (Output_def *def, int);
  
 
 Font_metric *select_encoded_font (Output_def *layout, SCM chain);
diff --git a/lily/output-def.cc b/lily/output-def.cc
index f9fbda9..3f60861 100644
--- a/lily/output-def.cc
+++ b/lily/output-def.cc
@@ -11,6 +11,7 @@
 #include "context-def.hh"
 #include "file-path.hh"
 #include "global-context.hh"
+#include "international.hh"
 #include "interval.hh"
 #include "main.hh"
 #include "output-def.hh"
@@ -128,7 +129,96 @@ Output_def::set_variable (SCM sym, SCM val)
   scm_module_define (scope_, sym, val);
 }
 
-  
+void
+Output_def::normalize ()
+{
+  Real paper_width;
+  SCM scm_paper_width = c_variable ("paper-width");
+ 
+  Real left_margin, left_margin_default;
+  SCM scm_left_margin_default = c_variable ("left-margin-default");
+  SCM scm_left_margin = c_variable ("left-margin");
+
+  Real right_margin, right_margin_default;
+  SCM scm_right_margin_default = c_variable ("right-margin-default");
+  SCM scm_right_margin = c_variable ("right-margin");
+
+  if (scm_paper_width == SCM_UNDEFINED 
+      || scm_left_margin_default == SCM_UNDEFINED 
+      || scm_right_margin_default == SCM_UNDEFINED) 
+    {
+      programming_error ("called normalize() on paper with missing settings");
+      return;
+    } 
+  else
+    {
+      paper_width = scm_to_double (scm_paper_width);
+      left_margin_default = scm_to_double (scm_left_margin_default);
+      right_margin_default = scm_to_double (scm_right_margin_default); 
+    }
+
+  Real line_width;
+  Real line_width_default = paper_width - left_margin_default - 
right_margin_default;
+  SCM scm_line_width = c_variable ("line-width");
+
+  if (scm_line_width == SCM_UNDEFINED)
+    {
+      left_margin = ((scm_left_margin == SCM_UNDEFINED) ? left_margin_default 
: scm_to_double(scm_left_margin));
+      right_margin = ((scm_right_margin == SCM_UNDEFINED) ? 
right_margin_default : scm_to_double(scm_right_margin)); 
+      line_width = paper_width - left_margin - right_margin;
+    }
+  else
+    {
+      line_width = scm_to_double (scm_line_width);
+      if (scm_left_margin == SCM_UNDEFINED)
+        {
+          if (scm_right_margin == SCM_UNDEFINED) // Vertically center systems 
if only line-width is given
+            {
+              left_margin = (paper_width - line_width) / 2;
+              right_margin = left_margin;
+            }
+          else
+            {
+              right_margin = scm_to_double (scm_right_margin);
+              left_margin = paper_width - line_width - right_margin; 
+            }
+        }
+      else
+        {
+          left_margin = scm_to_double (scm_left_margin);
+          right_margin = ((scm_right_margin == SCM_UNDEFINED) 
+                           ? (paper_width - line_width - left_margin) 
+                           : scm_to_double (scm_right_margin)); 
+        }
+    }
+ 
+  if (to_boolean (c_variable ("check-consistency")))
+    {
+      // Consistency checks. If values don't match, set defaults.
+      if (abs(paper_width - line_width - left_margin - right_margin) > 1e-6) 
+        {
+          line_width = line_width_default;
+          left_margin = left_margin_default;
+          right_margin = right_margin_default;
+          warning (_ ("margins do not fit with line-width, setting default 
values"));          
+        } 
+      else if ((left_margin < 0) || (right_margin < 0))
+        {
+          line_width = line_width_default;
+          left_margin = left_margin_default;
+          right_margin = right_margin_default;
+          warning (_ ("systems run off the page due to improper paper 
settings, setting default values"));
+        }
+    }
+
+  // Lilypond-book needs the possibility to crop the line-width by a given 
amount
+  line_width = line_width - robust_scm2double (c_variable 
("line-width-cropping"), 0);  
+
+  set_variable (ly_symbol2scm ("left-margin"), scm_from_double (left_margin));
+  set_variable (ly_symbol2scm ("right-margin"), scm_from_double 
(right_margin));
+  set_variable (ly_symbol2scm ("line-width"), scm_from_double (line_width));
+}
+ 
 /* FIXME.  This is broken until we have a generic way of
    putting lists inside the \layout block.  */
 Interval
diff --git a/lily/paper-book.cc b/lily/paper-book.cc
index 3db1321..12a7f09 100644
--- a/lily/paper-book.cc
+++ b/lily/paper-book.cc
@@ -159,12 +159,21 @@ Paper_book::output (SCM output_channel)
 {
   int first_page_number = robust_scm2int (paper_->c_variable 
("first-page-number"), 1);
   int first_performance_number = 0;
+
+  /* FIXME: We need a line-width for ps output (framework-ps.scm:92). If we 
don't have any, we take the paper-width
+     unless we know better which line-width to choose (e.g. if there are 
\bookparts with different line-widths)
+     and why we need it at all. */
+
+  if (paper_->c_variable ("line-width") == SCM_UNDEFINED)
+    paper_->set_variable (ly_symbol2scm ("line-width"), paper_->c_variable 
("paper-width"));
+ 
   if (!output_aux (output_channel,
                   true,
                   &first_page_number,
                   &first_performance_number))
     return;
-      
+    
+ 
   SCM scopes = SCM_EOL;
   if (ly_is_module (header_))
     scopes = scm_cons (header_, scopes);
diff --git a/ly/paper-defaults-init.ly b/ly/paper-defaults-init.ly
index 1ee92ed..d742115 100644
--- a/ly/paper-defaults-init.ly
+++ b/ly/paper-defaults-init.ly
@@ -1,96 +1,116 @@
 \version "2.12.0"
 
 \paper {
-  %%% WARNING
-  %%%
-  %%% If you add any new dimensions, don't forget to update
-  %%% the dimension-variables variable.  See paper.scm.
-
-  unit = #(ly:unit)
-  mm = 1.0
-  in = 25.4
-  pt = #(/ in 72.27)
-  cm = #(* 10 mm)
-
-  print-page-number = ##t
-
-  %%
-  %% 20pt staff, 5 pt = 1.75 mm
-  %%
-
-  output-scale = #1.7573
-
-  #(define-public book-title (marked-up-title 'bookTitleMarkup))
-  #(define-public score-title (marked-up-title 'scoreTitleMarkup))
-
-  %%
-  %% ugh. hard coded?
-  %%
-
-  #(layout-set-absolute-staff-size (* 20.0 pt))
-
-
-  #(define-public score-title-properties
-     '((is-title . #t)
-       (is-book-title . #f)))
-  #(define-public book-title-properties
-     '((is-title . #t)
-       (is-book-title . #t)))
-
-  %% Note: these are not scaled; they are in staff-spaces.
-  between-system-spacing = #'((space . 12) (minimum-distance . 8) (padding . 
1))
-  between-scores-system-spacing = #'((space . 14) (minimum-distance . 8) 
(padding . 1))
-  after-title-spacing = #'((space . 2) (padding . 0.5))
-  before-title-spacing = #'((space . 5) (padding . 0.5))
-  between-title-spacing = #'((space . 1) (padding . 0.5))
-  top-system-spacing = #'((space . 1) (padding . 1) (min-distance . 0))
-  top-title-spacing = #'((space . 1) (padding . 1) (min-distance . 0))
-  bottom-system-spacing = #'((space . 1) (padding . 1) (min-distance . 0) 
(stretchability . 5))
-
-  ragged-bottom = ##f
-
-  %%
-  %% looks best for shorter scores.
-  %%
-  ragged-last-bottom = ##t
-
-  %%
-  %% settings for the page breaker
-  %%
-  blank-last-page-force = 0
-  blank-after-score-page-force = 2
-  blank-page-force = 5
-
-  %%
-  %% To limit space between systems on a page with a lot of space left
-  %%
-  page-limit-inter-system-space = ##f
-  page-limit-inter-system-space-factor = 1.4
-
-  #(define font-defaults
-     '((font-encoding . fetaMusic)))
-
-  %%
-  %% the font encoding `latin1' is a dummy value for Pango fonts
-  %%
-  #(define text-font-defaults
-     `((font-encoding . latin1)
-       (baseline-skip . 3)
-       (word-space . 0.6)))
-
-  #(define page-breaking ly:optimal-breaking)
-
-  #(define make-header (marked-up-headfoot 'oddHeaderMarkup 'evenHeaderMarkup))
-  #(define make-footer (marked-up-headfoot 'oddFooterMarkup 'evenFooterMarkup))
-  #(set-paper-dimension-variables (current-module))
-
-  \include "titling-init.ly"
-
-  top-margin = 5 \mm
-  bottom-margin = 6 \mm
-  head-separation = 4 \mm
-  foot-separation = 4 \mm
-
-  first-page-number = #1
-  print-first-page-number =##f
-}
+
+    %%% WARNING
+    %%%
+    %%% If you add any new dimensions, don't forget to update
+    %%% the dimension-variables variable.  See paper.scm.
+    
+    unit = #(ly:unit)
+    mm = 1.0
+    in = 25.4
+    pt = #(/ in 72.27)
+    cm = #(* 10 mm)
+
+    print-page-number = ##t
+
+    %%
+    %% 20pt staff, 5 pt = 1.75 mm
+    %%
+
+    output-scale = #1.7573
+    
+    #(define-public book-title (marked-up-title 'bookTitleMarkup))
+    #(define-public score-title (marked-up-title 'scoreTitleMarkup))
+    
+    %%
+    %% ugh. hard coded?
+    %%
+
+    #(layout-set-absolute-staff-size (* 20.0 pt))
+
+
+    #(define-public score-title-properties
+      '((is-title . #t)
+       (is-book-title . #f)
+       ))
+    #(define-public book-title-properties
+      '((is-title . #t)
+       (is-book-title . #t)
+       ))
+    
+    %% Note: these are not scaled; they are in staff-spaces.
+    between-system-spacing = #'((space . 12) (minimum-distance . 8) (padding . 
1))
+    between-scores-system-spacing = #'((space . 14) (minimum-distance . 8) 
(padding . 1))
+    after-title-spacing = #'((space . 2) (padding . 0.5))
+    before-title-spacing = #'((space . 5) (padding . 0.5))
+    between-title-spacing = #'((space . 1) (padding . 0.5))
+    top-system-spacing = #'((space . 1) (padding . 1) (min-distance . 0))
+    top-title-spacing = #'((space . 1) (padding . 1) (min-distance . 0))
+    bottom-system-spacing = #'((space . 1) (padding . 1) (min-distance . 0) 
(stretchability . 5))
+
+    ragged-bottom = ##f
+
+    %%
+    %% looks best for shorter scores.
+    %%
+    ragged-last-bottom= ##t
+
+    %%
+    %% settings for the page breaker
+    %%
+    blank-last-page-force = 0
+    blank-after-score-page-force = 2
+    blank-page-force = 5
+
+    %%
+    %% To limit space between systems on a page with a lot of space left
+    %%
+    page-limit-inter-system-space = ##f
+    page-limit-inter-system-space-factor = 1.4
+
+    #(define font-defaults
+      '((font-encoding . fetaMusic)))
+
+    %%
+    %% the font encoding `latin1' is a dummy value for Pango fonts
+    %%
+    #(define text-font-defaults
+      `((font-encoding . latin1)
+       (baseline-skip . 3)
+       (word-space . 0.6)))
+
+    #(define page-breaking ly:optimal-breaking)
+
+    #(define write-page-layout (ly:get-option 'dump-tweaks))
+    #(define system-maximum-stretch-procedure
+       (lambda (line)
+        (if (stretchable-line? line)
+            (let ((height (line-height line)))
+              (/ (* height height) 80.0))
+            0.0)))
+
+%    #(define page-music-height default-page-music-height )
+%    #(define page-make-stencil default-page-make-stencil )
+
+    #(define make-header (marked-up-headfoot 'oddHeaderMarkup 
'evenHeaderMarkup))
+    #(define make-footer (marked-up-headfoot 'oddFooterMarkup 
'evenFooterMarkup))
+    #(set-paper-dimension-variables (current-module))
+
+    \include "titling-init.ly"
+
+    check-consistency = ##t
+
+    top-margin = 5 \mm
+    bottom-margin = 6 \mm
+
+    left-margin-default = 10 \mm
+    right-margin-default = 10 \mm   
+
+    head-separation = 4 \mm
+    foot-separation = 4 \mm
+
+    first-page-number = #1
+    print-first-page-number =##f
+  }
diff --git a/scm/paper.scm b/scm/paper.scm
index 48f4a46..ab26e44 100644
--- a/scm/paper.scm
+++ b/scm/paper.scm
@@ -16,13 +16,16 @@
                    indent
                    ledger-line-thickness
                    left-margin
+                    left-margin-default
                    line-thickness
                    line-width
+                    line-width-cropping
                    mm
                    paper-height
                    paper-width
                    pt
                    right-margin
+                    right-margin-default
                    short-indent
                    staff-height
                    staff-space
@@ -207,23 +210,16 @@ size. SZ is in points"
     ("f4" . (cons (* 210 mm) (* 330 mm)))
    ))
 
-;; todo: take dimension arguments.
+; todo: take dimension arguments.
 
 (define (set-paper-dimensions m w h)
   "M is a module (i.e. layout->scope_ )"
-  (let* ((mm (eval 'mm m)))
+  (begin
+    ;; page layout - what to do with (printer specific!) margin settings?
     (module-define! m 'paper-width w)
     (module-define! m 'paper-height h)
-    (module-define! m 'line-width (- w
-                                    (ly:modules-lookup (list m) 'left-margin 
(* 10 mm))
-                                    (ly:modules-lookup (list m) 'right-margin 
(* 10 mm))))
-
     (module-define! m 'indent (/ w 14))
-    (module-define! m 'short-indent 0)
-
-    ;; page layout - what to do with (printer specific!) margin settings?
-
-    ))
+    (module-define! m 'short-indent 0)))
 
 (define (internal-set-paper-size module name landscape?)
   (define (swap x)
diff --git a/scripts/lilypond-book.py b/scripts/lilypond-book.py
index dc035b4..0308ada 100644
--- a/scripts/lilypond-book.py
+++ b/scripts/lilypond-book.py
@@ -830,7 +830,7 @@ PREAMBLE_LY = '''%%%% Generated by %(program_name)s
 \paper {
   %(paper_string)s
   force-assignment = #""
-  line-width = #(- line-width (* mm  %(padding_mm)f))
+  line-width-cropping = %(padding_mm)f \mm
 }
 
 \layout {
-- 
1.6.0.2