Issue 4418/6 edits to docs, tests, and changelog

[lilypond.git] / Documentation / changes.tely

diff --git a/Documentation/changes.tely b/Documentation/changes.tely
index 906214b6a379919fb01e043b6f54deed4e46608a..45fbb4f885ae1eddf00440c97e376e3a5a7c4924 100644 (file)
--- a/Documentation/changes.tely
+++ b/Documentation/changes.tely
@@ -61,6 +61,46 @@ which scares away people.
 
 @end ignore
 
+@item
+LilyPond functions defined with @code{define-music-function},
+@code{define-event-function}, @code{define-scheme-function} and
+@code{define-void-function} can now be directly called from Scheme
+as if they were genuine Scheme procedures.  Argument checking and
+matching will still be performed in the same manner as when
+calling the function through LilyPond input.  This includes the
+insertion of defaults for optional arguments not matching their
+predicates.  Instead of using @code{\default} in the actual
+argument list for explicitly skipping a sequence of optional
+arguments, @code{*unspecified*} can be employed.
+
+@item
+Current input location and parser are now stored in GUILE fluids
+and can be referenced via the function calls @code{(*location*)}
+and @code{(*parser*)}.  Consequently, a lot of functions
+previously taking an explicit @code{parser} argument no longer do
+so.
+
+Functions defined with @code{define-music-function},
+@code{define-event-function}, @code{define-scheme-function} and
+@code{define-void-function} no longer use @code{parser} and
+@code{location} arguments.
+
+With those particular definitions, LilyPond will try to recognize
+legacy use of @code{parser} and @code{location} arguments,
+providing backwards-compatible semantics for some time.
+
+@item
+The @code{whiteout} grob property and @code{\whiteout} markup command
+now create a white background built from multiple displaced copies of
+the glyph in order to approximate the contours of its outline.
+The previous rounded box white background can be achieved with the
+new @code{whiteout-box} grob property and @code{\whiteout-box} markup
+command.  Setting the @code{whiteout} property to a number now sets
+the thickness of the white outline as a multiple of staff-line
+thickness.  Similarly, overriding the @code{thickness} property of
+the @code{\whiteout} markup command sets the thickness of the white
+outline it produces.
+
 @item
 In the "english" notename language, the long notenames for pitches
 with accidentals now contain a hyphen for better readability.  You