GDP LM 4.3.1 Work around for layer

The order of writing grobs with the same
value for 'layer is unpredictable, leading
to unpredictable examples in this section.

diff --git a/Documentation/user/tweaks.itely b/Documentation/user/tweaks.itely
index 8d8925bd89aa4688ef2c609d37fa52342c3711f2..e59614f71ac63a607987a914673620edb7393370 100644 (file)
--- a/Documentation/user/tweaks.itely
+++ b/Documentation/user/tweaks.itely
@@ -1006,8 +1006,8 @@ We see from the properties specified in the @code{grob-interface}
 page in the IR that the @code{transparent} property is a boolean.
 This
 should be set to @code{#t} to make the grob transparent.
 page in the IR that the @code{transparent} property is a boolean.
 This
 should be set to @code{#t} to make the grob transparent.

-In this next example let us make the time signature invisible 
-rather than the bar lines.  
+In this next example let us make the time signature invisible
+rather than the bar lines.

 To do this we need to find the grob name for the time signature.
 Back to
 the @q{All layout objects} page in the IR to find the properties
 To do this we need to find the grob name for the time signature.
 Back to
 the @q{All layout objects} page in the IR to find the properties


@@ -1028,10 +1028,10 @@ transparent is:
 @end lilypond
 
 @noindent
 @end lilypond
 
 @noindent

-The time signature is gone, but this command leaves a gap where 
+The time signature is gone, but this command leaves a gap where

 the time signature should be.  Maybe this is what is wanted for
 the time signature should be.  Maybe this is what is wanted for

-an exercise for the student to fill it in, but in other 
-circumstances a gap might be undesirable.  To remove it, the 
+an exercise for the student to fill it in, but in other
+circumstances a gap might be undesirable.  To remove it, the

 stencil for the time signature should be set to @code{#f}
 instead:
 
 stencil for the time signature should be set to @code{#f}
 instead:
 


@@ -1053,8 +1053,16 @@ leaves it where it is, but makes it invisible.
 @subheading color
 @cindex color property
 
 @subheading color
 @cindex color property
 

-Finally we could make the bar lines invisible by coloring
-them white.  The @code{grob-interface} specifies that the
+Finally let us try making the bar lines invisible by coloring
+them white.  (There is a difficulty with this in that the
+white bar line may or may not blank out the staff lines where
+they cross.  You may see in some of the examples below that this
+happens unpredictably.  The details of why this is so and how to
+control it are covered in @ruser{Painting objects white}.  But at
+the moment we are learning about color, so please just accept this
+limitation for now.)
+
+The @code{grob-interface} specifies that the

 color property value is a list, but there is no
 explanation of what that list should be.  The list it
 requires is actually a list of values in internal units,
 color property value is a list, but there is no
 explanation of what that list should be.  The list it
 requires is actually a list of values in internal units,


@@ -1080,7 +1088,7 @@ and again, we see the bar lines are not visible.  Note that
 a symbol, but a @emph{function}.  When called, it provides
 the list of internal values required to set the color to
 white.  The other colors in the normal list are functions
 a symbol, but a @emph{function}.  When called, it provides
 the list of internal values required to set the color to
 white.  The other colors in the normal list are functions

-too.  To convince yourself this is working you might like 
+too.  To convince yourself this is working you might like

 to change the color to one of the other functions in the
 list.
 
 to change the color to one of the other functions in the
 list.
 


@@ -1113,7 +1121,7 @@ an apostrophe and the two enclosed in brackets.
 
 There is yet a third function, one which converts RGB values into
 internal colors -- the @code{rgb-color} function.  This takes
 
 There is yet a third function, one which converts RGB values into
 internal colors -- the @code{rgb-color} function.  This takes

-three arguments giving the intensities of the red, green and 
+three arguments giving the intensities of the red, green and

 blue colors.  These take values in the range 0 to 1.  So to
 set the color to red the value should be @code{(rgb-color 1 0 0)}
 and to white it should be @code{(rgb-color 1 1 1)}:
 blue colors.  These take values in the range 0 to 1.  So to
 set the color to red the value should be @code{(rgb-color 1 0 0)}
 and to white it should be @code{(rgb-color 1 1 1)}: