Re: Ghostscript and new PDF interpreter

[Werner LEMBERG]

> [...] I don't see an immediate connection between the new PDF
> interpreter and file size increase (this is what "perfectly fine"
> was referring to).

Too much info is floating around, so here is a table that shows the
various possibilities we are currently investigating.

* Everything is based on commit 056784fcb9.

* All eight compilations were started from scratch using LuaTeX;
  `notation.pdf` was produced by `make bytecode; make doc`.

* To produce Cairo output I used
  `make doc ... LOCAL_LILYPOND_FLAGS="-dbackend=cairo"`.

* For the `-dNEWPDF=false` and `-dPreserveMarkedContent` builds I used
  the attached patches, which are mutually exclusive.


  LilyPond  extract              GS        size
  backend   pdfmark  GS          option    of NR  comments
  ------------------------------------------------------------------
  standard  no       9.56.1      --        44MB   ok

  standard  yes      9.56.1      --         6MB   many links missing
  standard  yes      9.56.1 [1]  NEWPDF=    8MB   ok
                                 false
  standard  yes      10.1   [2]  Preserve  29MB   ok
                                 Marked
                                 Content

  cairo     no       9.56.1      --        17MB   ok
  cairo     yes      9.56.1      --        16MB   many links missing
  cairo     yes      9.56.1      NEWPDF=   21MB   ok
                                 false
  cairo     yes      10.1        Preserve  21MB   ok
                                 Marked
                                 Content


     Werner


[1] The next GS version (appearing in March 2023) will no longer
    contain the old PDF engine.
[2] This is a self-compiled version 10.0.0 with a very small patch
    (already in the GS repository) that enables
    `-dPreserveMarkedContent`.

diff --git a/Documentation/GNUmakefile b/Documentation/GNUmakefile
index 3670e82546..c1f994480a 100644
--- a/Documentation/GNUmakefile
+++ b/Documentation/GNUmakefile
@@ -488,6 +488,7 @@ ifeq ($(USE_EXTRACTPDFMARK),yes)
            -sDEVICE=pdfwrite \
            -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dNEWPDF=false \
            -dColorConversionStrategy=/LeaveColorUnchanged \
            -dDownsampleMonoImages=false \
            -dDownsampleGrayImages=false \
@@ -794,6 +795,7 @@ $(outdir)/%.png: %.eps
        mkdir -p $(dir $@)
        gs -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dNEWPDF=false \
            -dTextAlphaBits=4 \
            -dGraphicsAlphaBits=4 \
            -q \
@@ -809,6 +811,7 @@ $(outdir)/%.pdf: %.eps
        mkdir -p $(dir $@)
        gs -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dNEWPDF=false \
            -q \
            -sDEVICE=pdfwrite \
            -dNOPAUSE \

diff --git a/Documentation/GNUmakefile b/Documentation/GNUmakefile
index 3670e82546..53d5f15277 100644
--- a/Documentation/GNUmakefile
+++ b/Documentation/GNUmakefile
@@ -488,6 +488,7 @@ ifeq ($(USE_EXTRACTPDFMARK),yes)
            -sDEVICE=pdfwrite \
            -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dPreserveMarkedContent=true \
            -dColorConversionStrategy=/LeaveColorUnchanged \
            -dDownsampleMonoImages=false \
            -dDownsampleGrayImages=false \
@@ -792,8 +793,10 @@ $(outdir)/%.jpg: %.jpg
 $(outdir)/%.png: %.eps
        $(call ly_progress,Making,$@,< eps)
        mkdir -p $(dir $@)
-       gs -dAutoRotatePages=/None \
+       $(GHOSTSCRIPT) \
+           -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dPreserveMarkedContent=true \
            -dTextAlphaBits=4 \
            -dGraphicsAlphaBits=4 \
            -q \
@@ -807,8 +810,10 @@ $(outdir)/%.png: %.eps
 $(outdir)/%.pdf: %.eps
        $(call ly_progress,Making,$@,< eps)
        mkdir -p $(dir $@)
-       gs -dAutoRotatePages=/None \
+       $(GHOSTSCRIPT) \
+           -dAutoRotatePages=/None \
            -dPrinted=false \
+           -dPreserveMarkedContent=true \
            -q \
            -sDEVICE=pdfwrite \
            -dNOPAUSE \
diff --git a/config.make.in b/config.make.in
index 346df53ebe..39e9844409 100644
--- a/config.make.in
+++ b/config.make.in
@@ -34,6 +34,7 @@ FONTCONFIG_LIBS = @FONTCONFIG_LIBS@
 FONTFORGE = @FONTFORGE@
 FONTFORGE_QUIET_OPTION = @FONTFORGE_QUIET_OPTION@
 FREETYPE2_LIBS = @FREETYPE2_LIBS@
+GHOSTSCRIPT = @GHOSTSCRIPT@
 GLIB_LIBS = @GLIB_LIBS@ @GOBJECT_LIBS@
 GS_API = @GS_API@
 GS920 = @GS920@