From fbf273dae953c2549d8f1ac2806df644e2681d11 Mon Sep 17 00:00:00 2001
From: tux <tux@goldenerreiter.org>
Date: Wed, 9 Aug 2023 16:39:17 +0200
Subject: [PATCH] smarter breaks in toc columns closes #2

---
 toc_include.ly | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/toc_include.ly b/toc_include.ly
index 3b98c1a..483125c 100644
--- a/toc_include.ly
+++ b/toc_include.ly
@@ -19,13 +19,21 @@
         (map (lambda (foo)
          (make-general-align-markup Y UP (make-override-markup '(baseline-skip . 1) (make-column-markup
           (let add-to-col ((lines restlines) (height-left height))
-            (let* ((finished (null? lines))
-                   (linestencil (if (not finished) (interpret-markup layout (cons (list (cons 'line-width line-width) (cons 'baseline-skip 1)) props) (markup #:center-align (car lines)))))
-                   (calc-height (- height-left (if finished 0 (interval-length (ly:stencil-extent linestencil Y))))))
-              (set! restlines lines)
-              (if (or (< calc-height 0) (null? lines))
-                (list)
-                (cons (markup #:stencil linestencil) (add-to-col (cdr lines) calc-height)))))))))
+            (set! restlines lines)
+            (if (null? lines)
+              '()
+              (let* ((line-to-stencil (lambda (line) (interpret-markup layout (cons (list (cons 'line-width line-width) (cons 'baseline-skip 1)) props) (markup line))))
+                     (stencil-height (lambda (stencil) (interval-length (ly:stencil-extent stencil Y))))
+                     (linestencil (line-to-stencil (car lines)))
+                     (calc-height (- height-left (stencil-height linestencil)))
+                     (calc-width (interval-length (ly:stencil-extent linestencil X)))
+                     (is-less-than-half-line-width (< calc-width (/ line-width 2.0)))
+                     (next-line-height (if (null? (cdr lines)) 0 (stencil-height (line-to-stencil (cadr lines)))))
+                     (no-space-for-next-line (and is-less-than-half-line-width (< (- calc-height next-line-height) 0)))
+                     )
+                (if (or (< calc-height 0) no-space-for-next-line)
+                  '()
+                  (cons (markup #:stencil linestencil) (add-to-col (cdr lines) calc-height))))))))))
           (make-list cols))))
      (if (null? restlines)
          (list)
@@ -182,8 +190,8 @@
   indexItemMarkup = \markup \with-link-symbol-ref #'index:label {
     \index-item-with-pattern
   }
-  indexSectionMarkup = \markup \override #'(baseline-skip . 1.5) \column {
-    \fill-line { \sans \bold \fontsize #3 \fromproperty #'index:text \null }
+  indexSectionMarkup = \markup \override #'(baseline-skip . 1.5) \left-column {
+    \sans \bold \fontsize #3 \fromproperty #'index:text
     \null
   }
   indexCategoryMarkup = \markup \override #'(baseline-skip . 1.5) \column {